From: Isaku Yamahata <[email protected]>
KVM TDX basic feature support
Hello. This is v13 the patch series vof KVM TDX support. This is based on
v6.3-rc1 + the following patch series.
Related patch series This patch is based on:
- fd-based approach for supporing KVM v10 and
https://lore.kernel.org/lkml/[email protected]/
[email protected]:sean-jc/linux.git x86/upm_base_support
- TDX host kernel support v10
https://lore.kernel.org/lkml/[email protected]/
The tree can be found at https://github.com/intel/tdx/tree/kvm-upstream
How to run/test: It's describe at https://github.com/intel/tdx/wiki/TDX-KVM
This patch still adopts freezing sept entry instead of detecting error of TDX
SEAMCALL because it's fragile to detect race of SEAMCALL on same Secure-EPT.
The error code of SEAMCALL doesn't necessarily provides information so that
the caller, KVM TDX code, can't reliable determin if it's due to race or bug.
Changes from v12:
- ABI change of KVM_TDX_VM_INIT
- Rename kvm_gfn_{private, shared} to kvm_gfn_to_{private, shared}
- Move APIC BASE MSI initialization to KVM_TDX_VCPU_INIT
- Fix MTRR patch
- Make MapGpa hypercall always pass it to user space VMM
- Split hooks to TDP MMU into two part. populating and zapping.
Thanks,
Isaku Yamahata
Changes from v11:
- ABI change of KVM_TDX_VM_INIT
- Split the hook of TDP MMU to not modify handle_changed_spte()
- Enhanced commit message on mtrr patch
- Made KVM_CAP_MAX_VCPUS to x86 specific
Changes from v10:
- rebased to v6.2-rc3
- support mtrr with its own patches
- Integrated fd-based private page v10
- Integrated TDX host kernel support v8
- Integrated kvm_init rework v2
- removed struct tdx_td_page and its initialization logic
- cleaned up mmio spte and require enable_mmio_caching=true for TDX
- removed dubious WARN_ON_ONCE()
- split a patch adding methods as nop into several patches
Changes from v9:
- rebased to v6.1-rc2
- Integrated fd-based private page v9 as prerequisite.
- Integrated TDX host kernel support v6
- TDP MMU: Make handle_change_spte() return value.
- TDX: removed seamcall_lock and return -EAGAIN so that TDP MMU can retry
Changes from v8:
- rebased to v6.0-rc7
- Integrated with kvm hardware initialization. Check all packages has at least
one online CPU when creating guest TD and refuse cpu offline during guest TDs
are running.
- Integrated fd-based private page v8 as prerequisite.
- TDP MMU: Introduced more callbacks instead of single callback.
Changes from v7:
- Use xarray to track whether GFN is private or shared. Drop SPTE_SHARED_MASK.
The complex state machine with SPTE_SHARED_MASK was ditched.
- Large page support is implemented. But will be posted as independent RFC patch.
- fd-based private page v7 is integrated. This is mostly same to Chao's patches.
It's in github.
Changes from v6:
- rebased to v5.19
Changes from v5:
- export __seamcall and use it
- move mutex lock from callee function of smp_call_on_cpu to the caller.
- rename mmu_prezap => flush_shadow_all_private() and tdx_mmu_release_hkid
- updated comment
- drop the use of tdh_mng_key.reclaimid(): as the function is for backward
compatibility to only return success
- struct kvm_tdx_cmd: metadata => flags, added __u64 error.
- make this ioctl systemwide ioctl
- ABI change to struct kvm_init_vm
- guest_tsc_khz: use kvm->arch.default_tsc_khz
- rename BUILD_BUG_ON_MEMCPY to MEMCPY_SAME_SIZE
- drop exporting kvm_set_tsc_khz().
- fix kvm_tdp_page_fault() for mtrr emulation
- rename it to kvm_gfn_shared_mask(), dropped kvm_gpa_shared_mask()
- drop kvm_is_private_gfn(), kept kvm_is_private_gpa()
keep kvm_{gfn, gpa}_private(), kvm_gpa_private()
- update commit message
- rename shadow_init_value => shadow_nonprsent_value
- added ept_violation_ve_test mode
- shadow_nonpresent_value => SHADOW_NONPRESENT_VALUE in tdp_mmu.c
- legacy MMU case
=> - mmu_topup_shadow_page_cache(), kvm_mmu_create()
- FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
- #VE warning:
- rename: REMOVED_SPTE => __REMOVED_SPTE, SHADOW_REMOVED_SPTE => REMOVED_SPTE
- merge into Like we discussed, this patch should be merged with patch
"KVM: x86/mmu: Allow non-zero init value for shadow PTE".
- fix pointed by Sagi. check !is_private check => (kvm_gfn_shared_mask && !is_private)
- introduce kvm_gfn_for_root(kvm, root, gfn)
- add only_shared argument to kvm_tdp_mmu_handle_gfn()
- use kvm_arch_dirty_log_supported()
- rename SPTE_PRIVATE_PROHIBIT to SPTE_SHARED_MASK.
- rename: is_private_prohibit_spte() => spte_shared_mask()
- fix: shadow_nonpresent_value => SHADOW_NONPRESENT_VALUE in comment
- dropped this patch as the change was merged into kvm/queue
- update vt_apicv_post_state_restore()
- use is_64_bit_hypercall()
- comment: expand MSMI -> Machine Check System Management Interrupt
- fixed TDX_SEPT_PFERR
- tdvmcall_p[1234]_{write, read}() => tdvmcall_a[0123]_{read,write}()
- rename tdmvcall_exit_readon() => tdvmcall_leaf()
- remove optional zero check of argument.
- do a check for static_call(kvm_x86_has_emulated_msr)(kvm, MSR_IA32_SMBASE)
in kvm_vcpu_ioctl_smi and __apic_accept_irq.
- WARN_ON_ONCE in tdx_smi_allowed and tdx_enable_smi_window.
- introduce vcpu_deliver_init to x86_ops
- sprinkeled KVM_BUG_ON()
Changes from v4:
- rebased to TDX host kernel patch series.
- include all the patches to make this patch series working.
- add [MARKER] patches to mark the patch layer clear.
---
* What's TDX?
TDX stands for Trust Domain Extensions, which extends Intel Virtual Machines
Extensions (VMX) to introduce a kind of virtual machine guest called a Trust
Domain (TD) for confidential computing.
A TD runs in a CPU mode that is designed to protect the confidentiality of its
memory contents and its CPU state from any other software, including the hosting
Virtual Machine Monitor (VMM), unless explicitly shared by the TD itself.
We have more detailed explanations below (***).
We have the high-level design of TDX KVM below (****).
In this patch series, we use "TD" or "guest TD" to differentiate it from the
current "VM" (Virtual Machine), which is supported by KVM today.
* The organization of this patch series
This patch series is on top of the patches series "TDX host kernel support":
https://lore.kernel.org/lkml/[email protected]/
This patch series is available at
https://github.com/intel/tdx/tree/kvm-upstream
The related repositories (TDX qemu, TDX OVMF(tdvf) etc) are described at
https://github.com/intel/tdx/wiki/TDX-KVM
The relations of the layers are depicted as follows.
The arrows below show the order of patch reviews we would like to have.
The below layers are chosen so that the device model, for example, qemu can
exercise each layering step by step. Check if TDX is supported, create TD VM,
create TD vcpu, allow vcpu running, populate TD guest private memory, and handle
vcpu exits/hypercalls/interrupts to run TD fully.
TDX vcpu
interrupt/exits/hypercall<------------\
^ |
| |
TD finalization |
^ |
| |
TDX EPT violation<------------\ |
^ | |
| | |
TD vcpu enter/exit | |
^ | |
| | |
TD vcpu creation/destruction | \-------KVM TDP MMU MapGPA
^ | ^
| | |
TD VM creation/destruction \---------------KVM TDP MMU hooks
^ ^
| |
TDX architectural definitions KVM TDP refactoring for TDX
^ ^
| |
TDX, VMX <--------TDX host kernel KVM MMU GPA stolen bits
coexistence support
The followings are explanations of each layer. Each layer has a dummy commit
that starts with [MARKER] in subject. It is intended to help to identify where
each layer starts.
TDX host kernel support:
https://lore.kernel.org/lkml/[email protected]/
The guts of system-wide initialization of TDX module. There is an
independent patch series for host x86. TDX KVM patches call functions
this patch series provides to initialize the TDX module.
TDX, VMX coexistence:
Infrastructure to allow TDX to coexist with VMX and trigger the
initialization of the TDX module.
This layer starts with
"KVM: VMX: Move out vmx_x86_ops to 'main.c' to wrap VMX and TDX"
TDX architectural definitions:
Add TDX architectural definitions and helper functions
This layer starts with
"[MARKER] The start of TDX KVM patch series: TDX architectural definitions".
TD VM creation/destruction:
Guest TD creation/destroy allocation and releasing of TDX specific vm
and vcpu structure. Create an initial guest memory image with TDX
measurement.
This layer starts with
"[MARKER] The start of TDX KVM patch series: TD VM creation/destruction".
TD vcpu creation/destruction:
guest TD creation/destroy Allocation and releasing of TDX specific vm
and vcpu structure. Create an initial guest memory image with TDX
measurement.
This layer starts with
"[MARKER] The start of TDX KVM patch series: TD vcpu creation/destruction"
TDX EPT violation:
Create an initial guest memory image with TDX measurement. Handle
secure EPT violations to populate guest pages with TDX SEAMCALLs.
This layer starts with
"[MARKER] The start of TDX KVM patch series: TDX EPT violation"
TD vcpu enter/exit:
Allow TDX vcpu to enter into TD and exit from TD. Save CPU state before
entering into TD. Restore CPU state after exiting from TD.
This layer starts with
"[MARKER] The start of TDX KVM patch series: TD vcpu enter/exit"
TD vcpu interrupts/exit/hypercall:
Handle various exits/hypercalls and allow interrupts to be injected so
that TD vcpu can continue running.
This layer starts with
"[MARKER] The start of TDX KVM patch series: TD vcpu exits/interrupts/hypercalls"
KVM MMU GPA shared bit:
Introduce framework to handle shared bit repurposed bit of GPA TDX
repurposed a bit of GPA to indicate shared or private. If it's shared,
it's the same as the conventional VMX EPT case. VMM can access shared
guest pages. If it's private, it's handled by Secure-EPT and the guest
page is encrypted.
This layer starts with
"[MARKER] The start of TDX KVM patch series: KVM MMU GPA stolen bits"
KVM TDP refactoring for TDX:
TDX Secure EPT requires different constants. e.g. initial value EPT
entry value etc. Various refactoring for those differences.
This layer starts with
"[MARKER] The start of TDX KVM patch series: KVM TDP refactoring for TDX"
KVM TDP MMU hooks:
Introduce framework to TDP MMU to add hooks in addition to direct EPT
access TDX added Secure EPT which is an enhancement to VMX EPT. Unlike
conventional VMX EPT, CPU can't directly read/write Secure EPT. Instead,
use TDX SEAMCALLs to operate on Secure EPT.
This layer starts with
"[MARKER] The start of TDX KVM patch series: KVM TDP MMU hooks"
KVM TDP MMU MapGPA:
Introduce framework to handle switching guest pages from private/shared
to shared/private. For a given GPA, a guest page can be assigned to a
private GPA or a shared GPA exclusively. With TDX MapGPA hypercall,
guest TD converts GPA assignments from private (or shared) to shared (or
private).
This layer starts with
"[MARKER] The start of TDX KVM patch series: KVM TDP MMU MapGPA "
KVM guest private memory: (not shown in the above diagram)
[PATCH v4 00/12] KVM: mm: fd-based approach for supporting KVM guest private
memory: https://lkml.org/lkml/2022/1/18/395
Guest private memory requires different memory management in KVM. The
patch proposes a way for it. Integration with TDX KVM.
(***)
* TDX module
A CPU-attested software module called the "TDX module" is designed to implement
the TDX architecture, and it is loaded by the UEFI firmware today. It can be
loaded by the kernel or driver at runtime, but in this patch series we assume
that the TDX module is already loaded and initialized.
The TDX module provides two main new logical modes of operation built upon the
new SEAM (Secure Arbitration Mode) root and non-root CPU modes added to the VMX
architecture. TDX root mode is mostly identical to the VMX root operation mode,
and the TDX functions (described later) are triggered by the new SEAMCALL
instruction with the desired interface function selected by an input operand
(leaf number, in RAX). TDX non-root mode is used for TD guest operation. TDX
non-root operation (i.e. "guest TD" mode) is similar to the VMX non-root
operation (i.e. guest VM), with changes and restrictions to better assure that
no other software or hardware has direct visibility of the TD memory and state.
TDX transitions between TDX root operation and TDX non-root operation include TD
Entries, from TDX root to TDX non-root mode, and TD Exits from TDX non-root to
TDX root mode. A TD Exit might be asynchronous, triggered by some external
event (e.g., external interrupt or SMI) or an exception, or it might be
synchronous, triggered by a TDCALL (TDG.VP.VMCALL) function.
TD VCPUs can be entered using SEAMCALL(TDH.VP.ENTER) by KVM. TDH.VP.ENTER is one
of the TDX interface functions as mentioned above, and "TDH" stands for Trust
Domain Host. Those host-side TDX interface functions are categorized into
various areas just for better organization, such as SYS (TDX module management),
MNG (TD management), VP (VCPU), PHYSMEM (physical memory), MEM (private memory),
etc. For example, SEAMCALL(TDH.SYS.INFO) returns the TDX module information.
TDCS (Trust Domain Control Structure) is the main control structure of a guest
TD, and encrypted (using the guest TD's ephemeral private key). At a high
level, TDCS holds information for controlling TD operation as a whole,
execution, EPTP, MSR bitmaps, etc that KVM needs to set it up. Note that MSR
bitmaps are held as part of TDCS (unlike VMX) because they are meant to have the
same value for all VCPUs of the same TD.
Trust Domain Virtual Processor State (TDVPS) is the root control structure of a
TD VCPU. It helps the TDX module control the operation of the VCPU, and holds
the VCPU state while the VCPU is not running. TDVPS is opaque to software and
DMA access, accessible only by using the TDX module interface functions (such as
TDH.VP.RD, TDH.VP.WR). TDVPS includes TD VMCS, and TD VMCS auxiliary structures,
such as virtual APIC page, virtualization exception information, etc.
Several VMX control structures (such as Shared EPT and Posted interrupt
descriptor) are directly managed and accessed by the host VMM. These control
structures are pointed to by fields in the TD VMCS.
The above means that 1) KVM needs to allocate different data structures for TDs,
2) KVM can reuse the existing code for TDs for some operations, 3) it needs to
define TD-specific handling for others. 3) Redirect operations to . 3)
Redirect operations to the TDX specific callbacks, like "if (is_td_vcpu(vcpu))
tdx_callback() else vmx_callback();".
*TD Private Memory
TD private memory is designed to hold TD private content, encrypted by the CPU
using the TD ephemeral key. An encryption engine holds a table of encryption
keys, and an encryption key is selected for each memory transaction based on a
Host Key Identifier (HKID). By design, the host VMM does not have access to the
encryption keys.
In the first generation of MKTME, HKID is "stolen" from the physical address by
allocating a configurable number of bits from the top of the physical
address. The HKID space is partitioned into shared HKIDs for legacy MKTME
accesses and private HKIDs for SEAM-mode-only accesses. We use 0 for the shared
HKID on the host so that MKTME can be opaque or bypassed on the host.
During TDX non-root operation (i.e. guest TD), memory accesses can be qualified
as either shared or private, based on the value of a new SHARED bit in the Guest
Physical Address (GPA). The CPU translates shared GPAs using the usual VMX EPT
(Extended Page Table) or "Shared EPT" (in this document), which resides in host
VMM memory. The Shared EPT is directly managed by the host VMM - the same as
with the current VMX. Since guest TDs usually require I/O, and the data exchange
needs to be done via shared memory, thus KVM needs to use the current EPT
functionality even for TDs.
* Secure EPT and Minoring using the TDP code
The CPU translates private GPAs using a separate Secure EPT. The Secure EPT
pages are encrypted and integrity-protected with the TD's ephemeral private
key. Secure EPT can be managed _indirectly_ by the host VMM, using the TDX
interface functions, and thus conceptually Secure EPT is a subset of EPT (why
"subset"). Since execution of such interface functions takes much longer time
than accessing memory directly, in KVM we use the existing TDP code to minor the
Secure EPT for the TD.
This way, we can effectively walk Secure EPT without using the TDX interface
functions.
* VM life cycle and TDX specific operations
The userspace VMM, such as QEMU, needs to build and treat TDs differently. For
example, a TD needs to boot in private memory, and the host software cannot copy
the initial image to private memory.
* TSC Virtualization
The TDX module helps TDs maintain reliable TSC (Time Stamp Counter) values
(e.g. consistent among the TD VCPUs) and the virtual TSC frequency is determined
by TD configuration, i.e. when the TD is created, not per VCPU. The current KVM
owns TSC virtualization for VMs, but the TDX module does for TDs.
* MCE support for TDs
The TDX module doesn't allow VMM to inject MCE. Instead PV way is needed for TD
to communicate with VMM. For now, KVM silently ignores MCE request by VMM. MSRs
related to MCE (e.g, MCE bank registers) can be naturally emulated by
paravirtualizing MSR access.
[1] For details, the specifications, [2], [3], [4], [5], [6], [7], are
available.
* Restrictions or future work
Some features are not included to reduce patch size. Those features are
addressed as future independent patch series.
- large page (2M, 1G)
- qemu gdb stub
- guest PMU
- and more
* Prerequisites
It's required to load the TDX module and initialize it. It's out of the scope
of this patch series. Another independent patch for the common x86 code is
planned. It defines CONFIG_INTEL_TDX_HOST and this patch series uses
CONFIG_INTEL_TDX_HOST. It's assumed that With CONFIG_INTEL_TDX_HOST=y, the TDX
module is initialized and ready for KVM to use the TDX module APIs for TDX guest
life cycle like tdh.mng.init are ready to use.
Concretely Global initialization, LP (Logical Processor) initialization, global
configuration, the key configuration, and TDMR and PAMT initialization are done.
The state of the TDX module is SYS_READY. Please refer to the TDX module
specification, the chapter Intel TDX Module Lifecycle State Machine
** Detecting the TDX module readiness.
TDX host patch series implements the detection of the TDX module availability
and its initialization so that KVM can use it. Also it manages Host KeyID
(HKID) assigned to guest TD.
The assumed APIs the TDX host patch series provides are
- const struct tdsysinfo_struct *tdx_get_sysinfo(void);
Return the system wide information about the TDX module. NULL if the TDX
isn't initialized.
- int tdx_enable(void);
Initialization of TDX module so that the TDX module is ready for KVM to use.
- extern u32 tdx_global_keyid __read_mostly;
global host key id that is used for the TDX module itself.
- u32 tdx_get_num_keyid(void);
return the number of available TDX private host key id.
- int tdx_keyid_alloc(void);
Allocate HKID for guest TD.
- void tdx_keyid_free(int keyid);
Free HKID for guest TD.
(****)
* TDX KVM high-level design
- Host key ID management
Host Key ID (HKID) needs to be assigned to each TDX guest for memory encryption.
It is assumed The TDX host patch series implements necessary functions,
u32 tdx_get_global_keyid(void), int tdx_keyid_alloc(void) and,
void tdx_keyid_free(int keyid).
- Data structures and VM type
Because TDX is different from VMX, define its own VM/VCPU structures, struct
kvm_tdx and struct vcpu_tdx instead of struct kvm_vmx and struct vcpu_vmx. To
identify the VM, introduce VM-type to specify which VM type, VMX (default) or
TDX, is used.
- VM life cycle and TDX specific operations
Re-purpose the existing KVM_MEMORY_ENCRYPT_OP to add TDX specific operations.
New commands are used to get the TDX system parameters, set TDX specific VM/VCPU
parameters, set initial guest memory and measurement.
The creation of TDX VM requires five additional operations in addition to the
conventional VM creation.
- Get KVM system capability to check if TDX VM type is supported
- VM creation (KVM_CREATE_VM)
- New: Get the TDX specific system parameters. KVM_TDX_GET_CAPABILITY.
- New: Set TDX specific VM parameters. KVM_TDX_INIT_VM.
- VCPU creation (KVM_CREATE_VCPU)
- New: Set TDX specific VCPU parameters. KVM_TDX_INIT_VCPU.
- New: Initialize guest memory as boot state and extend the measurement with
the memory. KVM_TDX_INIT_MEM_REGION.
- New: Finalize VM. KVM_TDX_FINALIZE. Complete measurement of the initial
TDX VM contents.
- VCPU RUN (KVM_VCPU_RUN)
- Protected guest state
Because the guest state (CPU state and guest memory) is protected, the KVM VMM
can't operate on them. For example, accessing CPU registers, injecting
exceptions, and accessing guest memory. Those operations are handled as
silently ignored, returning zero or initial reset value when it's requested via
KVM API ioctls.
VM/VCPU state and callbacks for TDX specific operations.
Define tdx specific VM state and VCPU state instead of VMX ones. Redirect
operations to TDX specific callbacks. "if (tdx) tdx_op() else vmx_op()".
Operations on the CPU state
silently ignore operations on the guest state. For example, the write to
CPU registers is ignored and the read from CPU registers returns 0.
. ignore access to CPU registers except for allowed ones.
. TSC: add a check if tsc is immutable and return an error. Because the KVM
implementation updates the internal tsc state and it's difficult to back
out those changes. Instead, skip the logic.
. dirty logging: add check if dirty logging is supported.
. exceptions/SMI/MCE/SIPI/INIT: silently ignore
Note: virtual external interrupt and NMI can be injected into TDX guests.
- KVM MMU integration
One bit of the guest physical address (bit 51 or 47) is repurposed to indicate if
the guest physical address is private (the bit is cleared) or shared (the bit is
set). The bits are called stolen bits.
- Stolen bits framework
systematically tracks which guest physical address, shared or private, is
used.
- Shared EPT and secure EPT
There are two EPTs. Shared EPT (the conventional one) and Secure
EPT(the new one). Shared EPT is handled the same for the stolen
bit set. Secure EPT points to private guest pages. To resolve
EPT violation, KVM walks one of two EPTs based on faulted GPA.
Because it's costly to access secure EPT during walking EPTs with
SEAMCALLs for the private guest physical address, another private
EPT is used as a shadow of Secure-EPT with the existing logic at
the cost of extra memory.
The following depicts the relationship.
KVM | TDX module
| | |
-------------+---------- | |
| | | |
V V | |
shared GPA private GPA | |
CPU shared EPT pointer KVM private EPT pointer | CPU secure EPT pointer
| | | |
| | | |
V V | V
shared EPT private EPT--------mirror----->Secure EPT
| | | |
| \--------------------+------\ |
| | | |
V | V V
shared guest page | private guest page
|
|
non-encrypted memory | encrypted memory
|
- Operating on Secure EPT
Use the TDX module APIs to operate on Secure EPT. To call the TDX API
during resolving EPT violation, add hooks to additional operation and wiring
it to TDX backend.
* References
[1] TDX specification
https://www.intel.com/content/www/us/en/developer/articles/technical/intel-trust-domain-extensions.html
[2] Intel Trust Domain Extensions (Intel TDX)
https://cdrdv2.intel.com/v1/dl/getContent/726790
[3] Intel CPU Architectural Extensions Specification
https://www.intel.com/content/dam/develop/external/us/en/documents-tps/intel-tdx-cpu-architectural-specification.pdf
[4] Intel TDX Module 1.0 Specification
https://www.intel.com/content/dam/develop/external/us/en/documents/tdx-module-1.0-public-spec-v0.931.pdf
[5] Intel TDX Loader Interface Specification
https://www.intel.com/content/dam/develop/external/us/en/documents-tps/intel-tdx-seamldr-interface-specification.pdf
[6] Intel TDX Guest-Hypervisor Communication Interface
https://cdrdv2.intel.com/v1/dl/getContent/726790
[7] Intel TDX Virtual Firmware Design Guide
https://www.intel.com/content/dam/develop/external/us/en/documents/tdx-virtual-firmware-design-guide-rev-1.01.pdf
[8] intel public github
kvm TDX branch: https://github.com/intel/tdx/tree/kvm
TDX guest branch: https://github.com/intel/tdx/tree/guest
qemu TDX https://github.com/intel/qemu-tdx
[9] TDVF
https://github.com/tianocore/edk2-staging/tree/TDVF
This was merged into EDK2 main branch. https://github.com/tianocore/edk2
Chao Gao (2):
KVM: x86/mmu: Assume guest MMIOs are shared
KVM: x86: Allow to update cached values in kvm_user_return_msrs w/o
wrmsr
Isaku Yamahata (88):
KVM: x86/vmx: Refactor KVM VMX module init/exit functions
KVM: TDX: Initialize the TDX module when loading the KVM intel kernel
module
KVM: TDX: Initialize logical processor when onlined
KVM: TDX: Add placeholders for TDX VM/vcpu structure
KVM: TDX: Make TDX VM type supported
[MARKER] The start of TDX KVM patch series: TDX architectural
definitions
KVM: TDX: Define TDX architectural definitions
KVM: TDX: Add C wrapper functions for SEAMCALLs to the TDX module
KVM: TDX: Add helper functions to print TDX SEAMCALL error
[MARKER] The start of TDX KVM patch series: TD VM creation/destruction
x86/cpu: Add helper functions to allocate/free TDX private host key id
x86/virt/tdx: Add a helper function to return system wide info about
TDX module
KVM: TDX: Add place holder for TDX VM specific mem_enc_op ioctl
KVM: x86, tdx: Make KVM_CAP_MAX_VCPUS backend specific
KVM: TDX: create/destroy VM structure
KVM: TDX: initialize VM with TDX specific parameters
KVM: TDX: Make pmu_intel.c ignore guest TD case
KVM: TDX: Refuse to unplug the last cpu on the package
[MARKER] The start of TDX KVM patch series: TD vcpu
creation/destruction
KVM: TDX: allocate/free TDX vcpu structure
KVM: TDX: Do TDX specific vcpu initialization
[MARKER] The start of TDX KVM patch series: KVM MMU GPA shared bits
KVM: x86/mmu: introduce config for PRIVATE KVM MMU
KVM: x86/mmu: Add address conversion functions for TDX shared bit of
GPA
[MARKER] The start of TDX KVM patch series: KVM TDP refactoring for
TDX
KVM: x86/mmu: Replace hardcoded value 0 for the initial value for SPTE
KVM: x86/mmu: Add Suppress VE bit to
shadow_mmio_mask/shadow_present_mask
KVM: x86/mmu: Track shadow MMIO value on a per-VM basis
KVM: x86/mmu: Disallow fast page fault on private GPA
KVM: VMX: Introduce test mode related to EPT violation VE
[MARKER] The start of TDX KVM patch series: KVM TDP MMU hooks
KVM: x86/tdp_mmu: Init role member of struct kvm_mmu_page at
allocation
KVM: x86/mmu: Add a new is_private member for union kvm_mmu_page_role
KVM: x86/mmu: Add a private pointer to struct kvm_mmu_page
KVM: Add flags to struct kvm_gfn_range
KVM: x86/tdp_mmu: Sprinkle __must_check
KVM: x86/tdp_mmu: Support TDX private mapping for TDP MMU
[MARKER] The start of TDX KVM patch series: TDX EPT violation
KVM: x86/mmu: Disallow dirty logging for x86 TDX
KVM: TDX: Require TDP MMU and mmio caching for TDX
KVM: TDX: TDP MMU TDX support
KVM: TDX: MTRR: implement get_mt_mask() for TDX
[MARKER] The start of TDX KVM patch series: TD finalization
KVM: TDX: Create initial guest memory
KVM: TDX: Finalize VM initialization
[MARKER] The start of TDX KVM patch series: TD vcpu enter/exit
KVM: TDX: Add helper assembly function to TDX vcpu
KVM: TDX: Implement TDX vcpu enter/exit path
KVM: TDX: vcpu_run: save/restore host state(host kernel gs)
KVM: TDX: restore host xsave state when exit from the guest TD
KVM: TDX: restore user ret MSRs
[MARKER] The start of TDX KVM patch series: TD vcpu
exits/interrupts/hypercalls
KVM: TDX: complete interrupts after tdexit
KVM: TDX: restore debug store when TD exit
KVM: TDX: handle vcpu migration over logical processor
KVM: x86: Add a switch_db_regs flag to handle TDX's auto-switched
behavior
KVM: TDX: remove use of struct vcpu_vmx from posted_interrupt.c
KVM: TDX: Implement interrupt injection
KVM: TDX: Implements vcpu request_immediate_exit
KVM: TDX: Implement methods to inject NMI
KVM: TDX: Add a place holder to handle TDX VM exit
KVM: TDX: handle EXIT_REASON_OTHER_SMI
KVM: TDX: handle ept violation/misconfig exit
KVM: TDX: handle EXCEPTION_NMI and EXTERNAL_INTERRUPT
KVM: TDX: Add a place holder for handler of TDX hypercalls
(TDG.VP.VMCALL)
KVM: TDX: handle KVM hypercall with TDG.VP.VMCALL
KVM: TDX: Add KVM Exit for TDX TDG.VP.VMCALL
KVM: TDX: Handle TDX PV CPUID hypercall
KVM: TDX: Handle TDX PV HLT hypercall
KVM: TDX: Handle TDX PV port io hypercall
KVM: TDX: Implement callbacks for MSR operations for TDX
KVM: TDX: Handle TDX PV rdmsr/wrmsr hypercall
KVM: TDX: Handle TDX PV report fatal error hypercall
KVM: TDX: Handle TDX PV map_gpa hypercall
KVM: TDX: Handle TDG.VP.VMCALL<GetTdVmCallInfo> hypercall
KVM: TDX: Silently discard SMI request
KVM: TDX: Silently ignore INIT/SIPI
KVM: TDX: Add methods to ignore guest instruction emulation
KVM: TDX: Add a method to ignore dirty logging
KVM: TDX: Add methods to ignore VMX preemption timer
KVM: TDX: Add methods to ignore accesses to TSC
KVM: TDX: Ignore setting up mce
KVM: TDX: Add a method to ignore for TDX to ignore hypercall patch
KVM: TDX: Add methods to ignore virtual apic related operation
Documentation/virt/kvm: Document on Trust Domain Extensions(TDX)
KVM: x86: design documentation on TDX support of x86 KVM TDP MMU
RFC: KVM: TDX: Make busy with S-EPT on entry bug
[MARKER] the end of (the first phase of) TDX KVM patch series
Sean Christopherson (20):
KVM: VMX: Move out vmx_x86_ops to 'main.c' to wrap VMX and TDX
KVM: x86: Introduce vm_type to differentiate default VMs from
confidential VMs
KVM: TDX: Add TDX "architectural" error codes
KVM: TDX: x86: Add ioctl to get TDX systemwide parameters
KVM: Allow page-sized MMU caches to be initialized with custom 64-bit
values
KVM: x86/mmu: Allow non-zero value for non-present SPTE and removed
SPTE
KVM: x86/mmu: Allow per-VM override of the TDP max page level
KVM: x86/tdp_mmu: Don't zap private pages for unsupported cases
KVM: VMX: Split out guts of EPT violation to common/exposed function
KVM: VMX: Move setting of EPT MMU masks to common VT-x code
KVM: TDX: Add accessors VMX VMCS helpers
KVM: TDX: Add load_mmu_pgd method for TDX
KVM: x86/mmu: Introduce kvm_mmu_map_tdp_page() for use by TDX
KVM: TDX: Add support for find pending IRQ in a protected local APIC
KVM: x86: Assume timer IRQ was injected if APIC state is proteced
KVM: VMX: Modify NMI and INTR handlers to take intr_info as function
argument
KVM: VMX: Move NMI/exception handler to common helper
KVM: x86: Split core of hypercall emulation to helper function
KVM: TDX: Handle TDX PV MMIO hypercall
KVM: TDX: Add methods to ignore accesses to CPU state
Yan Zhao (1):
KVM: x86/mmu: TDX: Do not enable page track for TD guest
Yao Yuan (1):
KVM: TDX: Handle vmentry failure for INTEL TD guest
Yuan Yao (1):
KVM: TDX: Retry seamcall when TDX_OPERAND_BUSY with operand SEPT
Documentation/virt/kvm/api.rst | 13 +-
Documentation/virt/kvm/index.rst | 3 +
Documentation/virt/kvm/intel-tdx.rst | 357 +++
Documentation/virt/kvm/tdx-tdp-mmu.rst | 417 ++++
arch/x86/events/intel/ds.c | 1 +
arch/x86/include/asm/kvm-x86-ops.h | 15 +
arch/x86/include/asm/kvm_host.h | 76 +-
arch/x86/include/asm/tdx.h | 76 +-
arch/x86/include/asm/vmx.h | 14 +
arch/x86/include/uapi/asm/kvm.h | 83 +
arch/x86/include/uapi/asm/vmx.h | 5 +-
arch/x86/kvm/Kconfig | 4 +
arch/x86/kvm/Makefile | 3 +-
arch/x86/kvm/cpuid.c | 7 +
arch/x86/kvm/cpuid.h | 2 +
arch/x86/kvm/irq.c | 3 +
arch/x86/kvm/lapic.c | 33 +-
arch/x86/kvm/lapic.h | 2 +
arch/x86/kvm/mmu.h | 31 +
arch/x86/kvm/mmu/mmu.c | 204 +-
arch/x86/kvm/mmu/mmu_internal.h | 111 +-
arch/x86/kvm/mmu/page_track.c | 3 +
arch/x86/kvm/mmu/paging_tmpl.h | 3 +-
arch/x86/kvm/mmu/spte.c | 22 +-
arch/x86/kvm/mmu/spte.h | 29 +-
arch/x86/kvm/mmu/tdp_iter.h | 14 +-
arch/x86/kvm/mmu/tdp_mmu.c | 436 +++-
arch/x86/kvm/mmu/tdp_mmu.h | 7 +-
arch/x86/kvm/smm.h | 7 +-
arch/x86/kvm/svm/svm.c | 8 +
arch/x86/kvm/vmx/common.h | 165 ++
arch/x86/kvm/vmx/main.c | 1217 ++++++++++
arch/x86/kvm/vmx/pmu_intel.c | 46 +-
arch/x86/kvm/vmx/pmu_intel.h | 28 +
arch/x86/kvm/vmx/posted_intr.c | 43 +-
arch/x86/kvm/vmx/posted_intr.h | 13 +
arch/x86/kvm/vmx/tdx.c | 2828 ++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 257 +++
arch/x86/kvm/vmx/tdx_arch.h | 168 ++
arch/x86/kvm/vmx/tdx_errno.h | 38 +
arch/x86/kvm/vmx/tdx_error.c | 21 +
arch/x86/kvm/vmx/tdx_ops.h | 237 ++
arch/x86/kvm/vmx/vmcs.h | 5 +
arch/x86/kvm/vmx/vmenter.S | 156 ++
arch/x86/kvm/vmx/vmx.c | 699 ++----
arch/x86/kvm/vmx/vmx.h | 52 +-
arch/x86/kvm/vmx/x86_ops.h | 258 +++
arch/x86/kvm/x86.c | 144 +-
arch/x86/kvm/x86.h | 4 +
arch/x86/virt/vmx/tdx/seamcall.S | 2 +
arch/x86/virt/vmx/tdx/tdx.c | 55 +-
arch/x86/virt/vmx/tdx/tdx.h | 54 -
include/linux/kvm_host.h | 12 +-
include/linux/kvm_types.h | 1 +
include/uapi/linux/kvm.h | 57 +
tools/arch/x86/include/uapi/asm/kvm.h | 95 +
virt/kvm/kvm_main.c | 46 +-
57 files changed, 7932 insertions(+), 758 deletions(-)
create mode 100644 Documentation/virt/kvm/intel-tdx.rst
create mode 100644 Documentation/virt/kvm/tdx-tdp-mmu.rst
create mode 100644 arch/x86/kvm/vmx/common.h
create mode 100644 arch/x86/kvm/vmx/main.c
create mode 100644 arch/x86/kvm/vmx/pmu_intel.h
create mode 100644 arch/x86/kvm/vmx/tdx.c
create mode 100644 arch/x86/kvm/vmx/tdx.h
create mode 100644 arch/x86/kvm/vmx/tdx_arch.h
create mode 100644 arch/x86/kvm/vmx/tdx_errno.h
create mode 100644 arch/x86/kvm/vmx/tdx_error.c
create mode 100644 arch/x86/kvm/vmx/tdx_ops.h
create mode 100644 arch/x86/kvm/vmx/x86_ops.h
base-commit: ef5f68cc1f829b492b19cd4df5af4454aa816b93
prerequisite-patch-id: 25c4778ca586ebfa8a1000b547569cf30c9cdbbb
prerequisite-patch-id: f15d178f9000430e0089c546756ab1d8d29341a7
prerequisite-patch-id: e162f31c8556dc9b1eebb52b153d2d4ae76d663f
prerequisite-patch-id: 2cec43d88e640b381516d6b5e3655478beab43b2
prerequisite-patch-id: d63f4f3eb7a5cea6ad36c3f3c24761993f599b7b
prerequisite-patch-id: 9d77fb0e8ce8c8c21e22ff3f26bd168eb5446df0
prerequisite-patch-id: 498e20857392d3ab0b290335f6bc4a646a9d8797
prerequisite-patch-id: 773bf14343711b6df1790f3c0e0bceec952be19c
prerequisite-patch-id: c1ff9950424897e617e2be2c96881714fb4aa2d2
prerequisite-patch-id: 8a420307f338a7a496e87649f200227816226880
prerequisite-patch-id: 94420af3725fc8b7d9b0bea2549f71c106dc6c78
prerequisite-patch-id: 0e93d19cb59f3a052a377a56ff0a4399046818aa
prerequisite-patch-id: 30f511fa04a93e4705c35c7430b1d53958af0fc3
prerequisite-patch-id: e5a5861d8d29f4fc750d0b7ac56872e43b911fcc
prerequisite-patch-id: 68bc54f6dbee57d34ec6397df8bd2d76f0e5b15e
prerequisite-patch-id: 301dbdf8448175ea609664c890a3694750ecf740
prerequisite-patch-id: ba8e6068bcef7865bb5523065e19edd49fbc02de
prerequisite-patch-id: 7a11e08c6b7b73cd3fd29809c155af5d5400a24f
prerequisite-patch-id: a123ed868b3ed76e35dfc4830e4c3e903464db64
prerequisite-patch-id: cb5d2a167bed556fe3b2aa26452ee53d5e7c4428
prerequisite-patch-id: 5618d2414a1ef641b4c247b5e28076f67a765b24
prerequisite-patch-id: 338234d708730ff22c40b3a8ffbcf6820e9e6381
prerequisite-patch-id: 265913c78c61a3f84975f2a427bc895319a64b64
prerequisite-patch-id: bda07e82c47928bff9f1fcc8d003c526a5a42b6b
prerequisite-patch-id: 909d82383aac39075f4a80325d7a0d09f060ffb6
prerequisite-patch-id: 7ae6c571e61a2dc52aa1470b088d57b87267047f
prerequisite-patch-id: cb32f271215dd2080619b4a794331c8b1c518ae6
prerequisite-patch-id: ffb4d5a65b230e2a6cfbedc4341287d520a215ee
prerequisite-patch-id: 3c93e412ef811eb92d0c9e7442108e57f4c0161d
prerequisite-patch-id: fcb992e10ec6d13af55850f8d91491232ea2ec3a
prerequisite-patch-id: 84ea8415128cdd984183fb216903c7f26e5b98bc
prerequisite-patch-id: ef1e2ca78a67eab67fa5c4ddb5300fae9f3d306f
prerequisite-patch-id: 98d71b86eaef7bcd4cf29b5537cb67526be47bcd
prerequisite-patch-id: f5b5d0a7e675b6b6302a5e2db6bf5c8218e0fda6
prerequisite-patch-id: 4451413560f58c6ce2f752b05085e3226878b256
prerequisite-patch-id: db10c9d1483c81148c3dfa0abe1ee3b80fe43a9b
prerequisite-patch-id: 716544cdd2e1ccec5efb4968a87f560689cebbca
prerequisite-patch-id: 772bc1da565064f37abb8bb7d6fa98a04684d005
prerequisite-patch-id: c54b90168fdfeb17ee9399f52e31b448f7cc0eaa
prerequisite-patch-id: 28b7f8abd1b17ebca095c4425dcb953f90752fb8
prerequisite-patch-id: df55ce2450aa405f904d1a5085ffe33b0ec6e399
prerequisite-patch-id: 51c897e5bf57ca32ba2ea71218144944296121a4
prerequisite-patch-id: bf5fd74736424429cee5bf645f85d09bb93a26be
prerequisite-patch-id: d0a71fc6ae91999a93703727e682532fe5d12c9a
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX requires to call a TDX initialization function per logical processor
(LP) before the LP uses TDX. When CPU is onlined, call the TDX LP
initialization API when cpu is onlined. If it failed refuse onlininig of
the cpu for simplicity instead of TDX avoiding the LP.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 15 ++++++++++++++-
arch/x86/kvm/vmx/tdx.c | 5 +++++
arch/x86/kvm/vmx/x86_ops.h | 2 ++
3 files changed, 21 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 5c9f5e00b3c4..d1c9c7f55050 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -9,6 +9,19 @@
static bool enable_tdx __ro_after_init;
module_param_named(tdx, enable_tdx, bool, 0444);
+static int vt_hardware_enable(void)
+{
+ int ret;
+
+ ret = vmx_hardware_enable();
+ if (!ret && enable_tdx) {
+ ret = tdx_hardware_enable();
+ if (ret)
+ vmx_hardware_disable();
+ }
+ return ret;
+}
+
static __init int vt_hardware_setup(void)
{
int ret;
@@ -40,7 +53,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.hardware_unsetup = vmx_hardware_unsetup,
- .hardware_enable = vmx_hardware_enable,
+ .hardware_enable = vt_hardware_enable,
.hardware_disable = vmx_hardware_disable,
.has_emulated_msr = vmx_has_emulated_msr,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index f3eb0138b60b..e51314bbb439 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -10,6 +10,11 @@
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+int tdx_hardware_enable(void)
+{
+ return tdx_cpu_enable();
+}
+
static int __init tdx_module_setup(void)
{
int ret;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 0f200aead411..010d02c86ba4 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -139,8 +139,10 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
#ifdef CONFIG_INTEL_TDX_HOST
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
+int tdx_hardware_enable(void);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
+static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX requires several initialization steps for KVM to create guest TDs.
Detect CPU feature, enable VMX (TDX is based on VMX), detect the TDX module
availability, and initialize it.
There are several options on when to initialize the TDX module. A.) kernel
module loading time, B.) the first guest TD creation time. A.) was chosen.
With B.), a user may hit an error of the TDX initialization when trying to
create the first guest TD. The machine that fails to initialize the TDX
module can't boot any guest TD further. Such failure is undesirable and a
surprise because the user expects that the machine can accommodate guest
TD, but actually not. So A.) is better than B.).
Introduce a module parameter, enable_tdx, to explicitly enable TDX KVM
support. It's off by default to keep same behavior for those who don't use
TDX. Implement hardware_setup method to detect TDX feature of CPU.
Because TDX requires all present CPUs to enable VMX (VMXON), the x86
specific kvm_arch_post_hardware_enable_setup overrides the existing weak
symbol of kvm_arch_post_hardware_enable_setup which is called at the KVM
module initialization.
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/Makefile | 1 +
arch/x86/kvm/vmx/main.c | 18 ++++++++++-
arch/x86/kvm/vmx/tdx.c | 63 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 39 +++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 10 ++++++
5 files changed, 130 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/kvm/vmx/tdx.c
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 0e894ae23cbc..4b01ab842ab7 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -25,6 +25,7 @@ kvm-$(CONFIG_KVM_SMM) += smm.o
kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
vmx/hyperv.o vmx/nested.o vmx/posted_intr.o vmx/main.o
kvm-intel-$(CONFIG_X86_SGX_KVM) += vmx/sgx.o
+kvm-intel-$(CONFIG_INTEL_TDX_HOST) += vmx/tdx.o
kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o \
svm/sev.o svm/hyperv.o
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 3f49e8e38b6b..5c9f5e00b3c4 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -6,6 +6,22 @@
#include "nested.h"
#include "pmu.h"
+static bool enable_tdx __ro_after_init;
+module_param_named(tdx, enable_tdx, bool, 0444);
+
+static __init int vt_hardware_setup(void)
+{
+ int ret;
+
+ ret = vmx_hardware_setup();
+ if (ret)
+ return ret;
+
+ enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
+
+ return 0;
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
( \
BIT(APICV_INHIBIT_REASON_DISABLE)| \
@@ -159,7 +175,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
- .hardware_setup = vmx_hardware_setup,
+ .hardware_setup = vt_hardware_setup,
.handle_intel_pt_intr = NULL,
.runtime_ops = &vt_x86_ops,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
new file mode 100644
index 000000000000..f3eb0138b60b
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <asm/tdx.h>
+
+#include "capabilities.h"
+#include "x86_ops.h"
+#include "x86.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+static int __init tdx_module_setup(void)
+{
+ int ret;
+
+ ret = tdx_enable();
+ if (ret) {
+ pr_info("Failed to initialize TDX module.\n");
+ return ret;
+ }
+
+ pr_info("TDX is supported.\n");
+ return 0;
+}
+
+static int __init tdx_cpu_enable_cpu(void *unused)
+{
+ return tdx_cpu_enable();
+}
+
+int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
+{
+ int r;
+
+ if (!enable_ept) {
+ pr_warn("Cannot enable TDX with EPT disabled\n");
+ return -EINVAL;
+ }
+
+ /* tdx_enable() in tdx_module_setup() requires cpus lock. */
+ cpus_read_lock();
+ /* TDX requires VMX. */
+ r = vmxon_all();
+ if (!r) {
+ int cpu;
+
+ /*
+ * Because tdx_cpu_enabel() acquire spin locks, on_each_cpu()
+ * can't be used.
+ */
+ for_each_online_cpu(cpu) {
+ if (smp_call_on_cpu(cpu, tdx_cpu_enable_cpu, NULL, false))
+ r = -EIO;
+ }
+ if (!r)
+ r = tdx_module_setup();
+ }
+ vmxoff_all();
+ cpus_read_unlock();
+
+ return r;
+}
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 3bbd07412f00..d23830d92f61 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8123,6 +8123,45 @@ static unsigned int vmx_handle_intel_pt_intr(void)
return 1;
}
+static __init void vmxon(void *arg)
+{
+ int cpu = raw_smp_processor_id();
+ u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
+ atomic_t *failed = arg;
+ int r;
+
+ if (cr4_read_shadow() & X86_CR4_VMXE) {
+ r = -EBUSY;
+ goto out;
+ }
+
+ r = kvm_cpu_vmxon(phys_addr);
+out:
+ if (r)
+ atomic_inc(failed);
+}
+
+__init int vmxon_all(void)
+{
+ atomic_t failed = ATOMIC_INIT(0);
+
+ on_each_cpu(vmxon, &failed, 1);
+
+ if (atomic_read(&failed))
+ return -EBUSY;
+ return 0;
+}
+
+static __init void vmxoff(void *junk)
+{
+ cpu_vmxoff();
+}
+
+__init void vmxoff_all(void)
+{
+ on_each_cpu(vmxoff, NULL, 1);
+}
+
static __init void vmx_setup_user_return_msrs(void)
{
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 051b5c4b5c2f..0f200aead411 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -20,6 +20,10 @@ bool kvm_is_vmx_supported(void);
int __init vmx_init(void);
void vmx_exit(void);
+__init int vmxon_all(void);
+__init void vmxoff_all(void);
+__init int vmx_hardware_setup(void);
+
extern struct kvm_x86_ops vt_x86_ops __initdata;
extern struct kvm_x86_init_ops vt_init_ops __initdata;
@@ -133,4 +137,10 @@ void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu);
#endif
void vmx_setup_mce(struct kvm_vcpu *vcpu);
+#ifdef CONFIG_INTEL_TDX_HOST
+int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
+#else
+static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
+#endif
+
#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
Add placeholders TDX VM/vcpu structure that overlays with VMX VM/vcpu
structures. Initialize VM structure size and vcpu size/align so that x86
KVM common code knows those size irrespective of VMX or TDX. Those
structures will be populated as guest creation logic develops.
Add helper functions to check if the VM is guest TD and add conversion
functions between KVM VM/VCPU and TDX VM/VCPU.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 9 ++++++++
arch/x86/kvm/vmx/tdx.c | 1 +
arch/x86/kvm/vmx/tdx.h | 50 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 60 insertions(+)
create mode 100644 arch/x86/kvm/vmx/tdx.h
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index d1c9c7f55050..5bc31c41bea9 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -5,6 +5,7 @@
#include "vmx.h"
#include "nested.h"
#include "pmu.h"
+#include "tdx.h"
static bool enable_tdx __ro_after_init;
module_param_named(tdx, enable_tdx, bool, 0444);
@@ -224,6 +225,14 @@ static int __init vt_init(void)
vt_x86_ops.vm_size = sizeof(struct kvm_vmx);
vcpu_size = sizeof(struct vcpu_vmx);
vcpu_align = __alignof__(struct vcpu_vmx);
+ if (enable_tdx) {
+ vt_x86_ops.vm_size = max_t(unsigned int, vt_x86_ops.vm_size,
+ sizeof(struct kvm_tdx));
+ vcpu_size = max_t(unsigned int, vcpu_size,
+ sizeof(struct vcpu_tdx));
+ vcpu_align = max_t(unsigned int, vcpu_align,
+ __alignof__(struct vcpu_tdx));
+ }
r = kvm_init(vcpu_size, vcpu_align, THIS_MODULE);
if (r)
goto err_kvm_init;
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index e51314bbb439..2f9eaefee249 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -6,6 +6,7 @@
#include "capabilities.h"
#include "x86_ops.h"
#include "x86.h"
+#include "tdx.h"
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
new file mode 100644
index 000000000000..2210c8c1e893
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __KVM_X86_TDX_H
+#define __KVM_X86_TDX_H
+
+#ifdef CONFIG_INTEL_TDX_HOST
+struct kvm_tdx {
+ struct kvm kvm;
+ /* TDX specific members follow. */
+};
+
+struct vcpu_tdx {
+ struct kvm_vcpu vcpu;
+ /* TDX specific members follow. */
+};
+
+static inline bool is_td(struct kvm *kvm)
+{
+ return kvm->arch.vm_type == KVM_X86_PROTECTED_VM;
+}
+
+static inline bool is_td_vcpu(struct kvm_vcpu *vcpu)
+{
+ return is_td(vcpu->kvm);
+}
+
+static inline struct kvm_tdx *to_kvm_tdx(struct kvm *kvm)
+{
+ return container_of(kvm, struct kvm_tdx, kvm);
+}
+
+static inline struct vcpu_tdx *to_tdx(struct kvm_vcpu *vcpu)
+{
+ return container_of(vcpu, struct vcpu_tdx, vcpu);
+}
+#else
+struct kvm_tdx {
+ struct kvm kvm;
+};
+
+struct vcpu_tdx {
+ struct kvm_vcpu vcpu;
+};
+
+static inline bool is_td(struct kvm *kvm) { return false; }
+static inline bool is_td_vcpu(struct kvm_vcpu *vcpu) { return false; }
+static inline struct kvm_tdx *to_kvm_tdx(struct kvm *kvm) { return NULL; }
+static inline struct vcpu_tdx *to_tdx(struct kvm_vcpu *vcpu) { return NULL; }
+#endif /* CONFIG_INTEL_TDX_HOST */
+
+#endif /* __KVM_X86_TDX_H */
--
2.25.1
From: Sean Christopherson <[email protected]>
KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions
to operate on VM. TDX doesn't allow VMM to operate VMCS directly.
Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to
indirectly operate those data structures. This means we must have a TDX
version of kvm_x86_ops.
The existing global struct kvm_x86_ops already defines an interface which
fits with TDX. But kvm_x86_ops is system-wide, not per-VM structure. To
allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers
"if (tdx) tdx_op() else vmx_op()" to switch VMX or TDX at run time.
To split the runtime switch, the VMX implementation, and the TDX
implementation, add main.c, and move out the vmx_x86_ops hooks in
preparation for adding TDX, which can coexist with VMX, i.e. KVM can run
both VMs and TDs. Use 'vt' for the naming scheme as a nod to VT-x and as a
concatenation of VmxTdx.
The current code looks as follows.
In vmx.c
static vmx_op() { ... }
static struct kvm_x86_ops vmx_x86_ops = {
.op = vmx_op,
initialization code
The eventually converted code will look like
In vmx.c, keep the VMX operations.
vmx_op() { ... }
VMX initialization
In tdx.c, define the TDX operations.
tdx_op() { ... }
TDX initialization
In x86_ops.h, declare the VMX and TDX operations.
vmx_op();
tdx_op();
In main.c, define common wrappers for VMX and TDX.
static vt_ops() { if (tdx) tdx_ops() else vmx_ops() }
static struct kvm_x86_ops vt_x86_ops = {
.op = vt_op,
initialization to call VMX and TDX initialization
Opportunistically, fix the name inconsistency from vmx_create_vcpu() and
vmx_free_vcpu() to vmx_vcpu_create() and vxm_vcpu_free().
Co-developed-by: Xiaoyao Li <[email protected]>
Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/Makefile | 2 +-
arch/x86/kvm/vmx/main.c | 167 +++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 370 ++++++++++---------------------------
arch/x86/kvm/vmx/x86_ops.h | 125 +++++++++++++
4 files changed, 394 insertions(+), 270 deletions(-)
create mode 100644 arch/x86/kvm/vmx/main.c
create mode 100644 arch/x86/kvm/vmx/x86_ops.h
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 80e3fe184d17..0e894ae23cbc 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -23,7 +23,7 @@ kvm-$(CONFIG_KVM_XEN) += xen.o
kvm-$(CONFIG_KVM_SMM) += smm.o
kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
- vmx/hyperv.o vmx/nested.o vmx/posted_intr.o
+ vmx/hyperv.o vmx/nested.o vmx/posted_intr.o vmx/main.o
kvm-intel-$(CONFIG_X86_SGX_KVM) += vmx/sgx.o
kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o \
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
new file mode 100644
index 000000000000..a59559ff140e
--- /dev/null
+++ b/arch/x86/kvm/vmx/main.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/moduleparam.h>
+
+#include "x86_ops.h"
+#include "vmx.h"
+#include "nested.h"
+#include "pmu.h"
+
+#define VMX_REQUIRED_APICV_INHIBITS \
+( \
+ BIT(APICV_INHIBIT_REASON_DISABLE)| \
+ BIT(APICV_INHIBIT_REASON_ABSENT) | \
+ BIT(APICV_INHIBIT_REASON_HYPERV) | \
+ BIT(APICV_INHIBIT_REASON_BLOCKIRQ) | \
+ BIT(APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED) | \
+ BIT(APICV_INHIBIT_REASON_APIC_ID_MODIFIED) | \
+ BIT(APICV_INHIBIT_REASON_APIC_BASE_MODIFIED) \
+)
+
+struct kvm_x86_ops vt_x86_ops __initdata = {
+ .name = KBUILD_MODNAME,
+
+ .check_processor_compatibility = vmx_check_processor_compat,
+
+ .hardware_unsetup = vmx_hardware_unsetup,
+
+ .hardware_enable = vmx_hardware_enable,
+ .hardware_disable = vmx_hardware_disable,
+ .has_emulated_msr = vmx_has_emulated_msr,
+
+ .vm_size = sizeof(struct kvm_vmx),
+ .vm_init = vmx_vm_init,
+ .vm_destroy = vmx_vm_destroy,
+
+ .vcpu_precreate = vmx_vcpu_precreate,
+ .vcpu_create = vmx_vcpu_create,
+ .vcpu_free = vmx_vcpu_free,
+ .vcpu_reset = vmx_vcpu_reset,
+
+ .prepare_switch_to_guest = vmx_prepare_switch_to_guest,
+ .vcpu_load = vmx_vcpu_load,
+ .vcpu_put = vmx_vcpu_put,
+
+ .update_exception_bitmap = vmx_update_exception_bitmap,
+ .get_msr_feature = vmx_get_msr_feature,
+ .get_msr = vmx_get_msr,
+ .set_msr = vmx_set_msr,
+ .get_segment_base = vmx_get_segment_base,
+ .get_segment = vmx_get_segment,
+ .set_segment = vmx_set_segment,
+ .get_cpl = vmx_get_cpl,
+ .get_cs_db_l_bits = vmx_get_cs_db_l_bits,
+ .set_cr0 = vmx_set_cr0,
+ .is_valid_cr4 = vmx_is_valid_cr4,
+ .set_cr4 = vmx_set_cr4,
+ .set_efer = vmx_set_efer,
+ .get_idt = vmx_get_idt,
+ .set_idt = vmx_set_idt,
+ .get_gdt = vmx_get_gdt,
+ .set_gdt = vmx_set_gdt,
+ .set_dr7 = vmx_set_dr7,
+ .sync_dirty_debug_regs = vmx_sync_dirty_debug_regs,
+ .cache_reg = vmx_cache_reg,
+ .get_rflags = vmx_get_rflags,
+ .set_rflags = vmx_set_rflags,
+ .get_if_flag = vmx_get_if_flag,
+
+ .flush_tlb_all = vmx_flush_tlb_all,
+ .flush_tlb_current = vmx_flush_tlb_current,
+ .flush_tlb_gva = vmx_flush_tlb_gva,
+ .flush_tlb_guest = vmx_flush_tlb_guest,
+
+ .vcpu_pre_run = vmx_vcpu_pre_run,
+ .vcpu_run = vmx_vcpu_run,
+ .handle_exit = vmx_handle_exit,
+ .skip_emulated_instruction = vmx_skip_emulated_instruction,
+ .update_emulated_instruction = vmx_update_emulated_instruction,
+ .set_interrupt_shadow = vmx_set_interrupt_shadow,
+ .get_interrupt_shadow = vmx_get_interrupt_shadow,
+ .patch_hypercall = vmx_patch_hypercall,
+ .inject_irq = vmx_inject_irq,
+ .inject_nmi = vmx_inject_nmi,
+ .inject_exception = vmx_inject_exception,
+ .cancel_injection = vmx_cancel_injection,
+ .interrupt_allowed = vmx_interrupt_allowed,
+ .nmi_allowed = vmx_nmi_allowed,
+ .get_nmi_mask = vmx_get_nmi_mask,
+ .set_nmi_mask = vmx_set_nmi_mask,
+ .enable_nmi_window = vmx_enable_nmi_window,
+ .enable_irq_window = vmx_enable_irq_window,
+ .update_cr8_intercept = vmx_update_cr8_intercept,
+ .set_virtual_apic_mode = vmx_set_virtual_apic_mode,
+ .set_apic_access_page_addr = vmx_set_apic_access_page_addr,
+ .refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
+ .load_eoi_exitmap = vmx_load_eoi_exitmap,
+ .apicv_post_state_restore = vmx_apicv_post_state_restore,
+ .required_apicv_inhibits = VMX_REQUIRED_APICV_INHIBITS,
+ .hwapic_irr_update = vmx_hwapic_irr_update,
+ .hwapic_isr_update = vmx_hwapic_isr_update,
+ .guest_apic_has_interrupt = vmx_guest_apic_has_interrupt,
+ .sync_pir_to_irr = vmx_sync_pir_to_irr,
+ .deliver_interrupt = vmx_deliver_interrupt,
+ .dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,
+
+ .set_tss_addr = vmx_set_tss_addr,
+ .set_identity_map_addr = vmx_set_identity_map_addr,
+ .get_mt_mask = vmx_get_mt_mask,
+
+ .get_exit_info = vmx_get_exit_info,
+
+ .vcpu_after_set_cpuid = vmx_vcpu_after_set_cpuid,
+
+ .has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
+
+ .get_l2_tsc_offset = vmx_get_l2_tsc_offset,
+ .get_l2_tsc_multiplier = vmx_get_l2_tsc_multiplier,
+ .write_tsc_offset = vmx_write_tsc_offset,
+ .write_tsc_multiplier = vmx_write_tsc_multiplier,
+
+ .load_mmu_pgd = vmx_load_mmu_pgd,
+
+ .check_intercept = vmx_check_intercept,
+ .handle_exit_irqoff = vmx_handle_exit_irqoff,
+
+ .request_immediate_exit = vmx_request_immediate_exit,
+
+ .sched_in = vmx_sched_in,
+
+ .cpu_dirty_log_size = PML_ENTITY_NUM,
+ .update_cpu_dirty_logging = vmx_update_cpu_dirty_logging,
+
+ .nested_ops = &vmx_nested_ops,
+
+ .pi_update_irte = vmx_pi_update_irte,
+ .pi_start_assignment = vmx_pi_start_assignment,
+
+#ifdef CONFIG_X86_64
+ .set_hv_timer = vmx_set_hv_timer,
+ .cancel_hv_timer = vmx_cancel_hv_timer,
+#endif
+
+ .setup_mce = vmx_setup_mce,
+
+#ifdef CONFIG_KVM_SMM
+ .smi_allowed = vmx_smi_allowed,
+ .enter_smm = vmx_enter_smm,
+ .leave_smm = vmx_leave_smm,
+ .enable_smi_window = vmx_enable_smi_window,
+#endif
+
+ .can_emulate_instruction = vmx_can_emulate_instruction,
+ .apic_init_signal_blocked = vmx_apic_init_signal_blocked,
+ .migrate_timers = vmx_migrate_timers,
+
+ .msr_filter_changed = vmx_msr_filter_changed,
+ .complete_emulated_msr = kvm_complete_insn_gp,
+
+ .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
+};
+
+struct kvm_x86_init_ops vt_init_ops __initdata = {
+ .hardware_setup = vmx_hardware_setup,
+ .handle_intel_pt_intr = NULL,
+
+ .runtime_ops = &vt_x86_ops,
+ .pmu_ops = &intel_pmu_ops,
+};
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index bcac3efcde41..47a9a647ae3a 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -66,6 +66,7 @@
#include "vmcs12.h"
#include "vmx.h"
#include "x86.h"
+#include "x86_ops.h"
#include "smm.h"
MODULE_AUTHOR("Qumranet");
@@ -524,8 +525,6 @@ static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx)
static unsigned long host_idt_base;
#if IS_ENABLED(CONFIG_HYPERV)
-static struct kvm_x86_ops vmx_x86_ops __initdata;
-
static bool __read_mostly enlightened_vmcs = true;
module_param(enlightened_vmcs, bool, 0444);
@@ -583,9 +582,8 @@ static __init void hv_init_evmcs(void)
}
if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
- vmx_x86_ops.enable_l2_tlb_flush
+ vt_x86_ops.enable_l2_tlb_flush
= hv_enable_l2_tlb_flush;
-
} else {
enlightened_vmcs = false;
}
@@ -1456,7 +1454,7 @@ void vmx_vcpu_load_vmcs(struct kvm_vcpu *vcpu, int cpu,
* Switches to specified vcpu, until a matching vcpu_put(), but assumes
* vcpu mutex is already taken.
*/
-static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -1467,7 +1465,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
vmx->host_debugctlmsr = get_debugctlmsr();
}
-static void vmx_vcpu_put(struct kvm_vcpu *vcpu)
+void vmx_vcpu_put(struct kvm_vcpu *vcpu)
{
vmx_vcpu_pi_put(vcpu);
@@ -1521,7 +1519,7 @@ void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
vmx->emulation_required = vmx_emulation_required(vcpu);
}
-static bool vmx_get_if_flag(struct kvm_vcpu *vcpu)
+bool vmx_get_if_flag(struct kvm_vcpu *vcpu)
{
return vmx_get_rflags(vcpu) & X86_EFLAGS_IF;
}
@@ -1627,8 +1625,8 @@ static int vmx_rtit_ctl_check(struct kvm_vcpu *vcpu, u64 data)
return 0;
}
-static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
- void *insn, int insn_len)
+bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
+ void *insn, int insn_len)
{
/*
* Emulation of instructions in SGX enclaves is impossible as RIP does
@@ -1712,7 +1710,7 @@ static int skip_emulated_instruction(struct kvm_vcpu *vcpu)
* Recognizes a pending MTF VM-exit and records the nested state for later
* delivery.
*/
-static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu)
+void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu)
{
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -1743,7 +1741,7 @@ static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu)
}
}
-static int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu)
+int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu)
{
vmx_update_emulated_instruction(vcpu);
return skip_emulated_instruction(vcpu);
@@ -1762,7 +1760,7 @@ static void vmx_clear_hlt(struct kvm_vcpu *vcpu)
vmcs_write32(GUEST_ACTIVITY_STATE, GUEST_ACTIVITY_ACTIVE);
}
-static void vmx_inject_exception(struct kvm_vcpu *vcpu)
+void vmx_inject_exception(struct kvm_vcpu *vcpu)
{
struct kvm_queued_exception *ex = &vcpu->arch.exception;
u32 intr_info = ex->vector | INTR_INFO_VALID_MASK;
@@ -1883,12 +1881,12 @@ u64 vmx_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu)
return kvm_caps.default_tsc_scaling_ratio;
}
-static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
+void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
{
vmcs_write64(TSC_OFFSET, offset);
}
-static void vmx_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier)
+void vmx_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier)
{
vmcs_write64(TSC_MULTIPLIER, multiplier);
}
@@ -1942,7 +1940,7 @@ static inline bool is_vmx_feature_control_msr_valid(struct vcpu_vmx *vmx,
return !(msr->data & ~valid_bits);
}
-static int vmx_get_msr_feature(struct kvm_msr_entry *msr)
+int vmx_get_msr_feature(struct kvm_msr_entry *msr)
{
switch (msr->index) {
case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
@@ -1959,7 +1957,7 @@ static int vmx_get_msr_feature(struct kvm_msr_entry *msr)
* Returns 0 on success, non-0 otherwise.
* Assumes vcpu_load() was already called.
*/
-static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmx_uret_msr *msr;
@@ -2138,7 +2136,7 @@ static u64 vmx_get_supported_debugctl(struct kvm_vcpu *vcpu, bool host_initiated
* Returns 0 on success, non-0 otherwise.
* Assumes vcpu_load() was already called.
*/
-static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmx_uret_msr *msr;
@@ -2471,7 +2469,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return ret;
}
-static void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
+void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
{
unsigned long guest_owned_bits;
@@ -2761,7 +2759,7 @@ static bool kvm_is_vmx_supported(void)
return true;
}
-static int vmx_check_processor_compat(void)
+int vmx_check_processor_compat(void)
{
int cpu = raw_smp_processor_id();
struct vmcs_config vmcs_conf;
@@ -2803,7 +2801,7 @@ static int kvm_cpu_vmxon(u64 vmxon_pointer)
return -EFAULT;
}
-static int vmx_hardware_enable(void)
+int vmx_hardware_enable(void)
{
int cpu = raw_smp_processor_id();
u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
@@ -2844,7 +2842,7 @@ static void vmclear_local_loaded_vmcss(void)
__loaded_vmcs_clear(v);
}
-static void vmx_hardware_disable(void)
+void vmx_hardware_disable(void)
{
vmclear_local_loaded_vmcss();
@@ -3156,7 +3154,7 @@ static void exit_lmode(struct kvm_vcpu *vcpu)
#endif
-static void vmx_flush_tlb_all(struct kvm_vcpu *vcpu)
+void vmx_flush_tlb_all(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -3186,7 +3184,7 @@ static inline int vmx_get_current_vpid(struct kvm_vcpu *vcpu)
return to_vmx(vcpu)->vpid;
}
-static void vmx_flush_tlb_current(struct kvm_vcpu *vcpu)
+void vmx_flush_tlb_current(struct kvm_vcpu *vcpu)
{
struct kvm_mmu *mmu = vcpu->arch.mmu;
u64 root_hpa = mmu->root.hpa;
@@ -3202,7 +3200,7 @@ static void vmx_flush_tlb_current(struct kvm_vcpu *vcpu)
vpid_sync_context(vmx_get_current_vpid(vcpu));
}
-static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
+void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
{
/*
* vpid_sync_vcpu_addr() is a nop if vpid==0, see the comment in
@@ -3211,7 +3209,7 @@ static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
vpid_sync_vcpu_addr(vmx_get_current_vpid(vcpu), addr);
}
-static void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu)
+void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu)
{
/*
* vpid_sync_context() is a nop if vpid==0, e.g. if enable_vpid==0 or a
@@ -3366,8 +3364,7 @@ u64 construct_eptp(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level)
return eptp;
}
-static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
- int root_level)
+void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level)
{
struct kvm *kvm = vcpu->kvm;
bool update_guest_cr3 = true;
@@ -3395,8 +3392,7 @@ static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
vmcs_writel(GUEST_CR3, guest_cr3);
}
-
-static bool vmx_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
+bool vmx_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
/*
* We operate under the default treatment of SMM, so VMX cannot be
@@ -3512,7 +3508,7 @@ void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
var->g = (ar >> 15) & 1;
}
-static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
+u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
{
struct kvm_segment s;
@@ -3589,14 +3585,14 @@ void __vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
vmcs_write32(sf->ar_bytes, vmx_segment_access_rights(var));
}
-static void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
+void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
{
__vmx_set_segment(vcpu, var, seg);
to_vmx(vcpu)->emulation_required = vmx_emulation_required(vcpu);
}
-static void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
+void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
{
u32 ar = vmx_read_guest_seg_ar(to_vmx(vcpu), VCPU_SREG_CS);
@@ -3604,25 +3600,25 @@ static void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
*l = (ar >> 13) & 1;
}
-static void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
dt->size = vmcs_read32(GUEST_IDTR_LIMIT);
dt->address = vmcs_readl(GUEST_IDTR_BASE);
}
-static void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
vmcs_write32(GUEST_IDTR_LIMIT, dt->size);
vmcs_writel(GUEST_IDTR_BASE, dt->address);
}
-static void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
dt->size = vmcs_read32(GUEST_GDTR_LIMIT);
dt->address = vmcs_readl(GUEST_GDTR_BASE);
}
-static void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
{
vmcs_write32(GUEST_GDTR_LIMIT, dt->size);
vmcs_writel(GUEST_GDTR_BASE, dt->address);
@@ -4094,7 +4090,7 @@ void pt_update_intercept_for_msr(struct kvm_vcpu *vcpu)
}
}
-static bool vmx_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
+bool vmx_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
void *vapic_page;
@@ -4114,7 +4110,7 @@ static bool vmx_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
return ((rvi & 0xf0) > (vppr & 0xf0));
}
-static void vmx_msr_filter_changed(struct kvm_vcpu *vcpu)
+void vmx_msr_filter_changed(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
u32 i;
@@ -4255,8 +4251,8 @@ static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
return 0;
}
-static void vmx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
- int trig_mode, int vector)
+void vmx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
+ int trig_mode, int vector)
{
struct kvm_vcpu *vcpu = apic->vcpu;
@@ -4418,7 +4414,7 @@ static u32 vmx_vmexit_ctrl(void)
~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER);
}
-static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
+void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -4689,7 +4685,7 @@ static int vmx_alloc_ipiv_pid_table(struct kvm *kvm)
return 0;
}
-static int vmx_vcpu_precreate(struct kvm *kvm)
+int vmx_vcpu_precreate(struct kvm *kvm)
{
return vmx_alloc_ipiv_pid_table(kvm);
}
@@ -4841,7 +4837,7 @@ static void __vmx_vcpu_reset(struct kvm_vcpu *vcpu)
vmx->pi_desc.sn = 1;
}
-static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
+void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -4900,12 +4896,12 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vmx_update_fb_clear_dis(vcpu, vmx);
}
-static void vmx_enable_irq_window(struct kvm_vcpu *vcpu)
+void vmx_enable_irq_window(struct kvm_vcpu *vcpu)
{
exec_controls_setbit(to_vmx(vcpu), CPU_BASED_INTR_WINDOW_EXITING);
}
-static void vmx_enable_nmi_window(struct kvm_vcpu *vcpu)
+void vmx_enable_nmi_window(struct kvm_vcpu *vcpu)
{
if (!enable_vnmi ||
vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & GUEST_INTR_STATE_STI) {
@@ -4916,7 +4912,7 @@ static void vmx_enable_nmi_window(struct kvm_vcpu *vcpu)
exec_controls_setbit(to_vmx(vcpu), CPU_BASED_NMI_WINDOW_EXITING);
}
-static void vmx_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
+void vmx_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
uint32_t intr;
@@ -4944,7 +4940,7 @@ static void vmx_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
vmx_clear_hlt(vcpu);
}
-static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
+void vmx_inject_nmi(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -5022,7 +5018,7 @@ bool vmx_nmi_blocked(struct kvm_vcpu *vcpu)
GUEST_INTR_STATE_NMI));
}
-static int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
if (to_vmx(vcpu)->nested.nested_run_pending)
return -EBUSY;
@@ -5044,7 +5040,7 @@ bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));
}
-static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
if (to_vmx(vcpu)->nested.nested_run_pending)
return -EBUSY;
@@ -5059,7 +5055,7 @@ static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
return !vmx_interrupt_blocked(vcpu);
}
-static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
+int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
{
void __user *ret;
@@ -5079,7 +5075,7 @@ static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
return init_rmode_tss(kvm, ret);
}
-static int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr)
+int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr)
{
to_kvm_vmx(kvm)->ept_identity_map_addr = ident_addr;
return 0;
@@ -5365,8 +5361,7 @@ static int handle_io(struct kvm_vcpu *vcpu)
return kvm_fast_pio(vcpu, size, port, in);
}
-static void
-vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
+void vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
{
/*
* Patch in the VMCALL instruction:
@@ -5576,7 +5571,7 @@ static int handle_dr(struct kvm_vcpu *vcpu)
return kvm_complete_insn_gp(vcpu, err);
}
-static void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu)
+void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu)
{
get_debugreg(vcpu->arch.db[0], 0);
get_debugreg(vcpu->arch.db[1], 1);
@@ -5595,7 +5590,7 @@ static void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu)
set_debugreg(DR6_RESERVED, 6);
}
-static void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val)
+void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val)
{
vmcs_writel(GUEST_DR7, val);
}
@@ -5866,7 +5861,7 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
return 1;
}
-static int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu)
+int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu)
{
if (vmx_emulation_required_with_pending_exception(vcpu)) {
kvm_prepare_emulation_failure_exit(vcpu);
@@ -6130,9 +6125,8 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
static const int kvm_vmx_max_exit_handlers =
ARRAY_SIZE(kvm_vmx_exit_handlers);
-static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
- u64 *info1, u64 *info2,
- u32 *intr_info, u32 *error_code)
+void vmx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
+ u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -6575,7 +6569,7 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
return 0;
}
-static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
+int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
{
int ret = __vmx_handle_exit(vcpu, exit_fastpath);
@@ -6663,7 +6657,7 @@ static noinstr void vmx_l1d_flush(struct kvm_vcpu *vcpu)
: "eax", "ebx", "ecx", "edx");
}
-static void vmx_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
+void vmx_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
{
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
int tpr_threshold;
@@ -6733,7 +6727,7 @@ void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
vmx_update_msr_bitmap_x2apic(vcpu);
}
-static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu)
+void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu)
{
struct page *page;
@@ -6761,7 +6755,7 @@ static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu)
put_page(page);
}
-static void vmx_hwapic_isr_update(int max_isr)
+void vmx_hwapic_isr_update(int max_isr)
{
u16 status;
u8 old;
@@ -6795,7 +6789,7 @@ static void vmx_set_rvi(int vector)
}
}
-static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
+void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
{
/*
* When running L2, updating RVI is only relevant when
@@ -6809,7 +6803,7 @@ static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
vmx_set_rvi(max_irr);
}
-static int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
+int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
int max_irr;
@@ -6855,7 +6849,7 @@ static int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
return max_irr;
}
-static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
{
if (!kvm_vcpu_apicv_active(vcpu))
return;
@@ -6866,7 +6860,7 @@ static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
vmcs_write64(EOI_EXIT_BITMAP3, eoi_exit_bitmap[3]);
}
-static void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu)
+void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -6929,7 +6923,7 @@ static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu)
vcpu->arch.at_instruction_boundary = true;
}
-static void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
+void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -6946,7 +6940,7 @@ static void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
* The kvm parameter can be NULL (module initialization, or invocation before
* VM creation). Be sure to check the kvm parameter before using it.
*/
-static bool vmx_has_emulated_msr(struct kvm *kvm, u32 index)
+bool vmx_has_emulated_msr(struct kvm *kvm, u32 index)
{
switch (index) {
case MSR_IA32_SMBASE:
@@ -7069,7 +7063,7 @@ static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
IDT_VECTORING_ERROR_CODE);
}
-static void vmx_cancel_injection(struct kvm_vcpu *vcpu)
+void vmx_cancel_injection(struct kvm_vcpu *vcpu)
{
__vmx_complete_interrupts(vcpu,
vmcs_read32(VM_ENTRY_INTR_INFO_FIELD),
@@ -7216,7 +7210,7 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
guest_state_exit_irqoff();
}
-static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
+fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
unsigned long cr3, cr4;
@@ -7379,7 +7373,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
return vmx_exit_handlers_fastpath(vcpu);
}
-static void vmx_vcpu_free(struct kvm_vcpu *vcpu)
+void vmx_vcpu_free(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -7390,7 +7384,7 @@ static void vmx_vcpu_free(struct kvm_vcpu *vcpu)
free_loaded_vmcs(vmx->loaded_vmcs);
}
-static int vmx_vcpu_create(struct kvm_vcpu *vcpu)
+int vmx_vcpu_create(struct kvm_vcpu *vcpu)
{
struct vmx_uret_msr *tsx_ctrl;
struct vcpu_vmx *vmx;
@@ -7499,7 +7493,7 @@ static int vmx_vcpu_create(struct kvm_vcpu *vcpu)
#define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
#define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
-static int vmx_vm_init(struct kvm *kvm)
+int vmx_vm_init(struct kvm *kvm)
{
if (!ple_gap)
kvm->arch.pause_in_guest = true;
@@ -7530,7 +7524,7 @@ static int vmx_vm_init(struct kvm *kvm)
return 0;
}
-static u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
u8 cache;
@@ -7702,7 +7696,7 @@ static void update_intel_pt_cfg(struct kvm_vcpu *vcpu)
vmx->pt_desc.ctl_bitmask &= ~(0xfULL << (32 + i * 4));
}
-static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
+void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -7838,7 +7832,7 @@ static __init void vmx_set_cpu_caps(void)
kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG);
}
-static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
+void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
{
to_vmx(vcpu)->req_immediate_exit = true;
}
@@ -7877,10 +7871,10 @@ static int vmx_check_intercept_io(struct kvm_vcpu *vcpu,
return intercept ? X86EMUL_UNHANDLEABLE : X86EMUL_CONTINUE;
}
-static int vmx_check_intercept(struct kvm_vcpu *vcpu,
- struct x86_instruction_info *info,
- enum x86_intercept_stage stage,
- struct x86_exception *exception)
+int vmx_check_intercept(struct kvm_vcpu *vcpu,
+ struct x86_instruction_info *info,
+ enum x86_intercept_stage stage,
+ struct x86_exception *exception)
{
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
@@ -7945,8 +7939,8 @@ static inline int u64_shl_div_u64(u64 a, unsigned int shift,
return 0;
}
-static int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
- bool *expired)
+int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
+ bool *expired)
{
struct vcpu_vmx *vmx;
u64 tscl, guest_tscl, delta_tsc, lapic_timer_advance_cycles;
@@ -7985,13 +7979,13 @@ static int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
return 0;
}
-static void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu)
+void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu)
{
to_vmx(vcpu)->hv_deadline_tsc = -1;
}
#endif
-static void vmx_sched_in(struct kvm_vcpu *vcpu, int cpu)
+void vmx_sched_in(struct kvm_vcpu *vcpu, int cpu)
{
if (!kvm_pause_in_guest(vcpu->kvm))
shrink_ple_window(vcpu);
@@ -8020,7 +8014,7 @@ void vmx_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
secondary_exec_controls_clearbit(vmx, SECONDARY_EXEC_ENABLE_PML);
}
-static void vmx_setup_mce(struct kvm_vcpu *vcpu)
+void vmx_setup_mce(struct kvm_vcpu *vcpu)
{
if (vcpu->arch.mcg_cap & MCG_LMCE_P)
to_vmx(vcpu)->msr_ia32_feature_control_valid_bits |=
@@ -8031,7 +8025,7 @@ static void vmx_setup_mce(struct kvm_vcpu *vcpu)
}
#ifdef CONFIG_KVM_SMM
-static int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
{
/* we need a nested vmexit to enter SMM, postpone if run is pending */
if (to_vmx(vcpu)->nested.nested_run_pending)
@@ -8039,7 +8033,7 @@ static int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
return !is_smm(vcpu);
}
-static int vmx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram)
+int vmx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -8060,7 +8054,7 @@ static int vmx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram)
return 0;
}
-static int vmx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram)
+int vmx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
int ret;
@@ -8081,18 +8075,18 @@ static int vmx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram)
return 0;
}
-static void vmx_enable_smi_window(struct kvm_vcpu *vcpu)
+void vmx_enable_smi_window(struct kvm_vcpu *vcpu)
{
/* RSM will cause a vmexit anyway. */
}
#endif
-static bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
+bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
{
return to_vmx(vcpu)->nested.vmxon && !is_guest_mode(vcpu);
}
-static void vmx_migrate_timers(struct kvm_vcpu *vcpu)
+void vmx_migrate_timers(struct kvm_vcpu *vcpu)
{
if (is_guest_mode(vcpu)) {
struct hrtimer *timer = &to_vmx(vcpu)->nested.preemption_timer;
@@ -8102,7 +8096,7 @@ static void vmx_migrate_timers(struct kvm_vcpu *vcpu)
}
}
-static void vmx_hardware_unsetup(void)
+void vmx_hardware_unsetup(void)
{
kvm_set_posted_intr_wakeup_handler(NULL);
@@ -8112,165 +8106,13 @@ static void vmx_hardware_unsetup(void)
free_kvm_area();
}
-#define VMX_REQUIRED_APICV_INHIBITS \
-( \
- BIT(APICV_INHIBIT_REASON_DISABLE)| \
- BIT(APICV_INHIBIT_REASON_ABSENT) | \
- BIT(APICV_INHIBIT_REASON_HYPERV) | \
- BIT(APICV_INHIBIT_REASON_BLOCKIRQ) | \
- BIT(APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED) | \
- BIT(APICV_INHIBIT_REASON_APIC_ID_MODIFIED) | \
- BIT(APICV_INHIBIT_REASON_APIC_BASE_MODIFIED) \
-)
-
-static void vmx_vm_destroy(struct kvm *kvm)
+void vmx_vm_destroy(struct kvm *kvm)
{
struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);
free_pages((unsigned long)kvm_vmx->pid_table, vmx_get_pid_table_order(kvm));
}
-static struct kvm_x86_ops vmx_x86_ops __initdata = {
- .name = KBUILD_MODNAME,
-
- .check_processor_compatibility = vmx_check_processor_compat,
-
- .hardware_unsetup = vmx_hardware_unsetup,
-
- .hardware_enable = vmx_hardware_enable,
- .hardware_disable = vmx_hardware_disable,
- .has_emulated_msr = vmx_has_emulated_msr,
-
- .vm_size = sizeof(struct kvm_vmx),
- .vm_init = vmx_vm_init,
- .vm_destroy = vmx_vm_destroy,
-
- .vcpu_precreate = vmx_vcpu_precreate,
- .vcpu_create = vmx_vcpu_create,
- .vcpu_free = vmx_vcpu_free,
- .vcpu_reset = vmx_vcpu_reset,
-
- .prepare_switch_to_guest = vmx_prepare_switch_to_guest,
- .vcpu_load = vmx_vcpu_load,
- .vcpu_put = vmx_vcpu_put,
-
- .update_exception_bitmap = vmx_update_exception_bitmap,
- .get_msr_feature = vmx_get_msr_feature,
- .get_msr = vmx_get_msr,
- .set_msr = vmx_set_msr,
- .get_segment_base = vmx_get_segment_base,
- .get_segment = vmx_get_segment,
- .set_segment = vmx_set_segment,
- .get_cpl = vmx_get_cpl,
- .get_cs_db_l_bits = vmx_get_cs_db_l_bits,
- .set_cr0 = vmx_set_cr0,
- .is_valid_cr4 = vmx_is_valid_cr4,
- .set_cr4 = vmx_set_cr4,
- .set_efer = vmx_set_efer,
- .get_idt = vmx_get_idt,
- .set_idt = vmx_set_idt,
- .get_gdt = vmx_get_gdt,
- .set_gdt = vmx_set_gdt,
- .set_dr7 = vmx_set_dr7,
- .sync_dirty_debug_regs = vmx_sync_dirty_debug_regs,
- .cache_reg = vmx_cache_reg,
- .get_rflags = vmx_get_rflags,
- .set_rflags = vmx_set_rflags,
- .get_if_flag = vmx_get_if_flag,
-
- .flush_tlb_all = vmx_flush_tlb_all,
- .flush_tlb_current = vmx_flush_tlb_current,
- .flush_tlb_gva = vmx_flush_tlb_gva,
- .flush_tlb_guest = vmx_flush_tlb_guest,
-
- .vcpu_pre_run = vmx_vcpu_pre_run,
- .vcpu_run = vmx_vcpu_run,
- .handle_exit = vmx_handle_exit,
- .skip_emulated_instruction = vmx_skip_emulated_instruction,
- .update_emulated_instruction = vmx_update_emulated_instruction,
- .set_interrupt_shadow = vmx_set_interrupt_shadow,
- .get_interrupt_shadow = vmx_get_interrupt_shadow,
- .patch_hypercall = vmx_patch_hypercall,
- .inject_irq = vmx_inject_irq,
- .inject_nmi = vmx_inject_nmi,
- .inject_exception = vmx_inject_exception,
- .cancel_injection = vmx_cancel_injection,
- .interrupt_allowed = vmx_interrupt_allowed,
- .nmi_allowed = vmx_nmi_allowed,
- .get_nmi_mask = vmx_get_nmi_mask,
- .set_nmi_mask = vmx_set_nmi_mask,
- .enable_nmi_window = vmx_enable_nmi_window,
- .enable_irq_window = vmx_enable_irq_window,
- .update_cr8_intercept = vmx_update_cr8_intercept,
- .set_virtual_apic_mode = vmx_set_virtual_apic_mode,
- .set_apic_access_page_addr = vmx_set_apic_access_page_addr,
- .refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
- .load_eoi_exitmap = vmx_load_eoi_exitmap,
- .apicv_post_state_restore = vmx_apicv_post_state_restore,
- .required_apicv_inhibits = VMX_REQUIRED_APICV_INHIBITS,
- .hwapic_irr_update = vmx_hwapic_irr_update,
- .hwapic_isr_update = vmx_hwapic_isr_update,
- .guest_apic_has_interrupt = vmx_guest_apic_has_interrupt,
- .sync_pir_to_irr = vmx_sync_pir_to_irr,
- .deliver_interrupt = vmx_deliver_interrupt,
- .dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,
-
- .set_tss_addr = vmx_set_tss_addr,
- .set_identity_map_addr = vmx_set_identity_map_addr,
- .get_mt_mask = vmx_get_mt_mask,
-
- .get_exit_info = vmx_get_exit_info,
-
- .vcpu_after_set_cpuid = vmx_vcpu_after_set_cpuid,
-
- .has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
-
- .get_l2_tsc_offset = vmx_get_l2_tsc_offset,
- .get_l2_tsc_multiplier = vmx_get_l2_tsc_multiplier,
- .write_tsc_offset = vmx_write_tsc_offset,
- .write_tsc_multiplier = vmx_write_tsc_multiplier,
-
- .load_mmu_pgd = vmx_load_mmu_pgd,
-
- .check_intercept = vmx_check_intercept,
- .handle_exit_irqoff = vmx_handle_exit_irqoff,
-
- .request_immediate_exit = vmx_request_immediate_exit,
-
- .sched_in = vmx_sched_in,
-
- .cpu_dirty_log_size = PML_ENTITY_NUM,
- .update_cpu_dirty_logging = vmx_update_cpu_dirty_logging,
-
- .nested_ops = &vmx_nested_ops,
-
- .pi_update_irte = vmx_pi_update_irte,
- .pi_start_assignment = vmx_pi_start_assignment,
-
-#ifdef CONFIG_X86_64
- .set_hv_timer = vmx_set_hv_timer,
- .cancel_hv_timer = vmx_cancel_hv_timer,
-#endif
-
- .setup_mce = vmx_setup_mce,
-
-#ifdef CONFIG_KVM_SMM
- .smi_allowed = vmx_smi_allowed,
- .enter_smm = vmx_enter_smm,
- .leave_smm = vmx_leave_smm,
- .enable_smi_window = vmx_enable_smi_window,
-#endif
-
- .can_emulate_instruction = vmx_can_emulate_instruction,
- .apic_init_signal_blocked = vmx_apic_init_signal_blocked,
- .migrate_timers = vmx_migrate_timers,
-
- .msr_filter_changed = vmx_msr_filter_changed,
- .complete_emulated_msr = kvm_complete_insn_gp,
-
- .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
-};
-
static unsigned int vmx_handle_intel_pt_intr(void)
{
struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
@@ -8336,9 +8178,7 @@ static void __init vmx_setup_me_spte_mask(void)
kvm_mmu_set_me_spte_mask(0, me_mask);
}
-static struct kvm_x86_init_ops vmx_init_ops __initdata;
-
-static __init int hardware_setup(void)
+__init int vmx_hardware_setup(void)
{
unsigned long host_bndcfgs;
struct desc_ptr dt;
@@ -8407,16 +8247,16 @@ static __init int hardware_setup(void)
* using the APIC_ACCESS_ADDR VMCS field.
*/
if (!flexpriority_enabled)
- vmx_x86_ops.set_apic_access_page_addr = NULL;
+ vt_x86_ops.set_apic_access_page_addr = NULL;
if (!cpu_has_vmx_tpr_shadow())
- vmx_x86_ops.update_cr8_intercept = NULL;
+ vt_x86_ops.update_cr8_intercept = NULL;
#if IS_ENABLED(CONFIG_HYPERV)
if (ms_hyperv.nested_features & HV_X64_NESTED_GUEST_MAPPING_FLUSH
&& enable_ept) {
- vmx_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
- vmx_x86_ops.tlb_remote_flush_with_range =
+ vt_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
+ vt_x86_ops.tlb_remote_flush_with_range =
hv_remote_flush_tlb_with_range;
}
#endif
@@ -8432,7 +8272,7 @@ static __init int hardware_setup(void)
if (!cpu_has_vmx_apicv())
enable_apicv = 0;
if (!enable_apicv)
- vmx_x86_ops.sync_pir_to_irr = NULL;
+ vt_x86_ops.sync_pir_to_irr = NULL;
if (!enable_apicv || !cpu_has_vmx_ipiv())
enable_ipiv = false;
@@ -8468,7 +8308,7 @@ static __init int hardware_setup(void)
enable_pml = 0;
if (!enable_pml)
- vmx_x86_ops.cpu_dirty_log_size = 0;
+ vt_x86_ops.cpu_dirty_log_size = 0;
if (!cpu_has_vmx_preemption_timer())
enable_preemption_timer = false;
@@ -8493,9 +8333,9 @@ static __init int hardware_setup(void)
}
if (!enable_preemption_timer) {
- vmx_x86_ops.set_hv_timer = NULL;
- vmx_x86_ops.cancel_hv_timer = NULL;
- vmx_x86_ops.request_immediate_exit = __kvm_request_immediate_exit;
+ vt_x86_ops.set_hv_timer = NULL;
+ vt_x86_ops.cancel_hv_timer = NULL;
+ vt_x86_ops.request_immediate_exit = __kvm_request_immediate_exit;
}
kvm_caps.supported_mce_cap |= MCG_LMCE_P;
@@ -8506,9 +8346,9 @@ static __init int hardware_setup(void)
if (!enable_ept || !enable_pmu || !cpu_has_vmx_intel_pt())
pt_mode = PT_MODE_SYSTEM;
if (pt_mode == PT_MODE_HOST_GUEST)
- vmx_init_ops.handle_intel_pt_intr = vmx_handle_intel_pt_intr;
+ vt_init_ops.handle_intel_pt_intr = vmx_handle_intel_pt_intr;
else
- vmx_init_ops.handle_intel_pt_intr = NULL;
+ vt_init_ops.handle_intel_pt_intr = NULL;
setup_default_sgx_lepubkeyhash();
@@ -8531,14 +8371,6 @@ static __init int hardware_setup(void)
return r;
}
-static struct kvm_x86_init_ops vmx_init_ops __initdata = {
- .hardware_setup = hardware_setup,
- .handle_intel_pt_intr = NULL,
-
- .runtime_ops = &vmx_x86_ops,
- .pmu_ops = &intel_pmu_ops,
-};
-
static void vmx_cleanup_l1d_flush(void)
{
if (vmx_l1d_flush_pages) {
@@ -8582,7 +8414,7 @@ static int __init vmx_init(void)
*/
hv_init_evmcs();
- r = kvm_x86_vendor_init(&vmx_init_ops);
+ r = kvm_x86_vendor_init(&vt_init_ops);
if (r)
return r;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
new file mode 100644
index 000000000000..e9ec4d259ff5
--- /dev/null
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -0,0 +1,125 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __KVM_X86_VMX_X86_OPS_H
+#define __KVM_X86_VMX_X86_OPS_H
+
+#include <linux/kvm_host.h>
+
+#include <asm/virtext.h>
+
+#include "x86.h"
+
+__init int vmx_hardware_setup(void);
+
+extern struct kvm_x86_ops vt_x86_ops __initdata;
+extern struct kvm_x86_init_ops vt_init_ops __initdata;
+
+void vmx_hardware_unsetup(void);
+int vmx_check_processor_compat(void);
+int vmx_hardware_enable(void);
+void vmx_hardware_disable(void);
+int vmx_vm_init(struct kvm *kvm);
+void vmx_vm_destroy(struct kvm *kvm);
+int vmx_vcpu_precreate(struct kvm *kvm);
+int vmx_vcpu_create(struct kvm_vcpu *vcpu);
+int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu);
+fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu);
+void vmx_vcpu_free(struct kvm_vcpu *vcpu);
+void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
+void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
+void vmx_vcpu_put(struct kvm_vcpu *vcpu);
+int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath);
+void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu);
+int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu);
+void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu);
+int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
+#ifdef CONFIG_KVM_SMM
+int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection);
+int vmx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram);
+int vmx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram);
+void vmx_enable_smi_window(struct kvm_vcpu *vcpu);
+#endif
+bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
+ void *insn, int insn_len);
+int vmx_check_intercept(struct kvm_vcpu *vcpu,
+ struct x86_instruction_info *info,
+ enum x86_intercept_stage stage,
+ struct x86_exception *exception);
+bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu);
+void vmx_migrate_timers(struct kvm_vcpu *vcpu);
+void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu);
+void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu);
+bool vmx_check_apicv_inhibit_reasons(enum kvm_apicv_inhibit reason);
+void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr);
+void vmx_hwapic_isr_update(int max_isr);
+bool vmx_guest_apic_has_interrupt(struct kvm_vcpu *vcpu);
+int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu);
+void vmx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
+ int trig_mode, int vector);
+void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu);
+bool vmx_has_emulated_msr(struct kvm *kvm, u32 index);
+void vmx_msr_filter_changed(struct kvm_vcpu *vcpu);
+void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
+void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu);
+int vmx_get_msr_feature(struct kvm_msr_entry *msr);
+int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
+u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg);
+void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
+void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
+int vmx_get_cpl(struct kvm_vcpu *vcpu);
+void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l);
+void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
+void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
+void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
+bool vmx_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
+int vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer);
+void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
+void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
+void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
+void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
+void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val);
+void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu);
+void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg);
+unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu);
+void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
+bool vmx_get_if_flag(struct kvm_vcpu *vcpu);
+void vmx_flush_tlb_all(struct kvm_vcpu *vcpu);
+void vmx_flush_tlb_current(struct kvm_vcpu *vcpu);
+void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr);
+void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu);
+void vmx_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask);
+u32 vmx_get_interrupt_shadow(struct kvm_vcpu *vcpu);
+void vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall);
+void vmx_inject_irq(struct kvm_vcpu *vcpu, bool reinjected);
+void vmx_inject_nmi(struct kvm_vcpu *vcpu);
+void vmx_inject_exception(struct kvm_vcpu *vcpu);
+void vmx_cancel_injection(struct kvm_vcpu *vcpu);
+int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection);
+int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection);
+bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu);
+void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
+void vmx_enable_nmi_window(struct kvm_vcpu *vcpu);
+void vmx_enable_irq_window(struct kvm_vcpu *vcpu);
+void vmx_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr);
+void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu);
+void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu);
+void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
+int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr);
+int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr);
+u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
+void vmx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
+ u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code);
+u64 vmx_get_l2_tsc_offset(struct kvm_vcpu *vcpu);
+u64 vmx_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu);
+void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset);
+void vmx_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier);
+void vmx_request_immediate_exit(struct kvm_vcpu *vcpu);
+void vmx_sched_in(struct kvm_vcpu *vcpu, int cpu);
+void vmx_update_cpu_dirty_logging(struct kvm_vcpu *vcpu);
+#ifdef CONFIG_X86_64
+int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
+ bool *expired);
+void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu);
+#endif
+void vmx_setup_mce(struct kvm_vcpu *vcpu);
+
+#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
From: Sean Christopherson <[email protected]>
Unlike default VMs, confidential VMs (Intel TDX and AMD SEV-ES) don't allow
some operations (e.g., memory read/write, register state access, etc).
Introduce vm_type to track the type of the VM to x86 KVM. Other arch KVMs
already use vm_type, KVM_INIT_VM accepts vm_type, and x86 KVM callback
vm_init accepts vm_type. So follow them. Further, a different policy can
be made based on vm_type. Define KVM_X86_DEFAULT_VM for default VM as
default and define KVM_X86_TDX_VM for Intel TDX VM. The wrapper function
will be defined as "bool is_td(kvm) { return vm_type == VM_TYPE_TDX; }"
Add a capability KVM_CAP_VM_TYPES to effectively allow device model,
e.g. qemu, to query what VM types are supported by KVM. This (introduce a
new capability and add vm_type) is chosen to align with other arch KVMs
that have VM types already. Other arch KVMs use different names to query
supported vm types and there is no common name for it, so new name was
chosen.
Co-developed-by: Xiaoyao Li <[email protected]>
Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
Documentation/virt/kvm/api.rst | 4 +++-
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/svm/svm.c | 7 +++++++
arch/x86/kvm/vmx/main.c | 1 +
arch/x86/kvm/vmx/vmx.c | 5 +++++
arch/x86/kvm/vmx/x86_ops.h | 1 +
arch/x86/kvm/x86.c | 8 +++++++-
arch/x86/kvm/x86.h | 2 ++
tools/arch/x86/include/uapi/asm/kvm.h | 3 +++
10 files changed, 31 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 15754ef8470f..7a34efd31dcc 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -150,7 +150,9 @@ You probably want to use 0 as machine type.
X86:
^^^^
-Supported X86 VM types can be queried via KVM_CAP_VM_TYPES.
+Supported X86 VM types can be queried via KVM_CAP_VM_TYPES, which returns the
+bitmap of supported vm types. The 1-setting of bit @n means vm type with value
+@n is supported.
S390:
^^^^^
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 8dc345cc6318..eac4b65d1b01 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -20,6 +20,7 @@ KVM_X86_OP(hardware_disable)
KVM_X86_OP(hardware_unsetup)
KVM_X86_OP(has_emulated_msr)
KVM_X86_OP(vcpu_after_set_cpuid)
+KVM_X86_OP(is_vm_type_supported)
KVM_X86_OP(vm_init)
KVM_X86_OP_OPTIONAL(vm_destroy)
KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d9fc5a1c7442..00c25f6ab871 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1561,6 +1561,7 @@ struct kvm_x86_ops {
bool (*has_emulated_msr)(struct kvm *kvm, u32 index);
void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
+ bool (*is_vm_type_supported)(unsigned long vm_type);
unsigned int vm_size;
int (*vm_init)(struct kvm *kvm);
void (*vm_destroy)(struct kvm *kvm);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 252e7f37e4e2..687df130fbad 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4682,6 +4682,12 @@ static void svm_vm_destroy(struct kvm *kvm)
sev_vm_destroy(kvm);
}
+static bool svm_is_vm_type_supported(unsigned long type)
+{
+ /* FIXME: Check if CPU is capable of SEV. */
+ return __kvm_is_vm_type_supported(type);
+}
+
static int svm_vm_init(struct kvm *kvm)
{
if (!pause_filter_count || !pause_filter_thresh)
@@ -4710,6 +4716,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
.vcpu_free = svm_vcpu_free,
.vcpu_reset = svm_vcpu_reset,
+ .is_vm_type_supported = svm_is_vm_type_supported,
.vm_size = sizeof(struct kvm_svm),
.vm_init = svm_vm_init,
.vm_destroy = svm_vm_destroy,
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 5bc31c41bea9..e36d392c2d40 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -58,6 +58,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.hardware_disable = vmx_hardware_disable,
.has_emulated_msr = vmx_has_emulated_msr,
+ .is_vm_type_supported = vmx_is_vm_type_supported,
.vm_size = sizeof(struct kvm_vmx),
.vm_init = vmx_vm_init,
.vm_destroy = vmx_vm_destroy,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index d23830d92f61..8134c77860d4 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7486,6 +7486,11 @@ int vmx_vcpu_create(struct kvm_vcpu *vcpu)
return err;
}
+bool vmx_is_vm_type_supported(unsigned long type)
+{
+ return type == KVM_X86_DEFAULT_VM;
+}
+
#define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
#define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 010d02c86ba4..30961fdbce10 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -32,6 +32,7 @@ void vmx_hardware_unsetup(void);
int vmx_check_processor_compat(void);
int vmx_hardware_enable(void);
void vmx_hardware_disable(void);
+bool vmx_is_vm_type_supported(unsigned long type);
int vmx_vm_init(struct kvm *kvm);
void vmx_vm_destroy(struct kvm *kvm);
int vmx_vcpu_precreate(struct kvm *kvm);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2125fcaa3973..27ab684f8374 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4356,12 +4356,18 @@ static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu,
return 0;
}
-static bool kvm_is_vm_type_supported(unsigned long type)
+bool __kvm_is_vm_type_supported(unsigned long type)
{
return type == KVM_X86_DEFAULT_VM ||
(type == KVM_X86_PROTECTED_VM &&
IS_ENABLED(CONFIG_KVM_PROTECTED_VM) && tdp_enabled);
}
+EXPORT_SYMBOL_GPL(__kvm_is_vm_type_supported);
+
+static bool kvm_is_vm_type_supported(unsigned long type)
+{
+ return static_call(kvm_x86_is_vm_type_supported)(type);
+}
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index a8167b47b8c8..ef1282c7de8d 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -8,6 +8,8 @@
#include "kvm_cache_regs.h"
#include "kvm_emulate.h"
+bool __kvm_is_vm_type_supported(unsigned long type);
+
struct kvm_caps {
/* control of guest tsc rate supported? */
bool has_tsc_control;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 7f467fe05d42..6afbfbb32d56 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -559,4 +559,7 @@ struct kvm_pmu_event_filter {
#define KVM_VCPU_TSC_CTRL 0 /* control group for the timestamp counter (TSC) */
#define KVM_VCPU_TSC_OFFSET 0 /* attribute for the TSC offset */
+#define KVM_X86_DEFAULT_VM 0
+#define KVM_X86_PROTECTED_VM 1
+
#endif /* _ASM_X86_KVM_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
NOTE: This patch is in position of the patch series for developers to be
able to test codes during the middle of the patch series although this
patch series doesn't provide functional features until the all the patches
of this patch series. When merging this patch series, this patch can be
moved to the end.
As first step TDX VM support, return that TDX VM type supported to device
model, e.g. qemu. The callback to create guest TD is vm_init callback for
KVM_CREATE_VM.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 18 ++++++++++++++++--
arch/x86/kvm/vmx/tdx.c | 6 ++++++
arch/x86/kvm/vmx/vmx.c | 5 -----
arch/x86/kvm/vmx/x86_ops.h | 3 ++-
4 files changed, 24 insertions(+), 8 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index e36d392c2d40..c8548004802a 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -23,6 +23,12 @@ static int vt_hardware_enable(void)
return ret;
}
+static bool vt_is_vm_type_supported(unsigned long type)
+{
+ return type == KVM_X86_DEFAULT_VM ||
+ (enable_tdx && tdx_is_vm_type_supported(type));
+}
+
static __init int vt_hardware_setup(void)
{
int ret;
@@ -36,6 +42,14 @@ static __init int vt_hardware_setup(void)
return 0;
}
+static int vt_vm_init(struct kvm *kvm)
+{
+ if (is_td(kvm))
+ return -EOPNOTSUPP; /* Not ready to create guest TD yet. */
+
+ return vmx_vm_init(kvm);
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
( \
BIT(APICV_INHIBIT_REASON_DISABLE)| \
@@ -58,9 +72,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.hardware_disable = vmx_hardware_disable,
.has_emulated_msr = vmx_has_emulated_msr,
- .is_vm_type_supported = vmx_is_vm_type_supported,
+ .is_vm_type_supported = vt_is_vm_type_supported,
.vm_size = sizeof(struct kvm_vmx),
- .vm_init = vmx_vm_init,
+ .vm_init = vt_vm_init,
.vm_destroy = vmx_vm_destroy,
.vcpu_precreate = vmx_vcpu_precreate,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 2f9eaefee249..36738904c26a 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -30,6 +30,12 @@ static int __init tdx_module_setup(void)
return 0;
}
+bool tdx_is_vm_type_supported(unsigned long type)
+{
+ /* enable_tdx check is done by the caller. */
+ return type == KVM_X86_PROTECTED_VM;
+}
+
static int __init tdx_cpu_enable_cpu(void *unused)
{
return tdx_cpu_enable();
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 8134c77860d4..d23830d92f61 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7486,11 +7486,6 @@ int vmx_vcpu_create(struct kvm_vcpu *vcpu)
return err;
}
-bool vmx_is_vm_type_supported(unsigned long type)
-{
- return type == KVM_X86_DEFAULT_VM;
-}
-
#define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
#define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 30961fdbce10..b2c74c1b5bbd 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -32,7 +32,6 @@ void vmx_hardware_unsetup(void);
int vmx_check_processor_compat(void);
int vmx_hardware_enable(void);
void vmx_hardware_disable(void);
-bool vmx_is_vm_type_supported(unsigned long type);
int vmx_vm_init(struct kvm *kvm);
void vmx_vm_destroy(struct kvm *kvm);
int vmx_vcpu_precreate(struct kvm *kvm);
@@ -141,9 +140,11 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
#ifdef CONFIG_INTEL_TDX_HOST
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
int tdx_hardware_enable(void);
+bool tdx_is_vm_type_supported(unsigned long type);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
+static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TDX architectural
definitions.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/index.rst | 2 ++
.../virt/kvm/intel-tdx-layer-status.rst | 29 +++++++++++++++++++
2 files changed, 31 insertions(+)
create mode 100644 Documentation/virt/kvm/intel-tdx-layer-status.rst
diff --git a/Documentation/virt/kvm/index.rst b/Documentation/virt/kvm/index.rst
index ad13ec55ddfe..7f5f803fa87a 100644
--- a/Documentation/virt/kvm/index.rst
+++ b/Documentation/virt/kvm/index.rst
@@ -19,3 +19,5 @@ KVM
vcpu-requests
halt-polling
review-checklist
+
+ intel-tdx-layer-status.rst
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
new file mode 100644
index 000000000000..f11ea701dc19
--- /dev/null
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -0,0 +1,29 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================================
+Intel Trust Dodmain Extensions(TDX)
+===================================
+
+Layer status
+============
+What qemu can do
+----------------
+- TDX VM TYPE is exposed to Qemu.
+- Qemu can try to create VM of TDX VM type and then fails.
+
+Patch Layer status
+------------------
+ Patch layer Status
+
+* TDX, VMX coexistence: Applied
+* TDX architectural definitions: Applying
+* TD VM creation/destruction: Not yet
+* TD vcpu creation/destruction: Not yet
+* TDX EPT violation: Not yet
+* TD finalization: Not yet
+* TD vcpu enter/exit: Not yet
+* TD vcpu interrupts/exit/hypercall: Not yet
+
+* KVM MMU GPA shared bits: Not yet
+* KVM TDP refactoring for TDX: Not yet
+* KVM TDP MMU hooks: Not yet
--
2.25.1
From: Isaku Yamahata <[email protected]>
Define architectural definitions for KVM to issue the TDX SEAMCALLs.
Structures and values that are architecturally defined in the TDX module
specifications the chapter of ABI Reference.
Co-developed-by: Sean Christopherson <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx_arch.h | 168 ++++++++++++++++++++++++++++++++++++
1 file changed, 168 insertions(+)
create mode 100644 arch/x86/kvm/vmx/tdx_arch.h
diff --git a/arch/x86/kvm/vmx/tdx_arch.h b/arch/x86/kvm/vmx/tdx_arch.h
new file mode 100644
index 000000000000..942a0e561a7b
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx_arch.h
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* architectural constants/data definitions for TDX SEAMCALLs */
+
+#ifndef __KVM_X86_TDX_ARCH_H
+#define __KVM_X86_TDX_ARCH_H
+
+#include <linux/types.h>
+
+/*
+ * TDX SEAMCALL API function leaves
+ */
+#define TDH_VP_ENTER 0
+#define TDH_MNG_ADDCX 1
+#define TDH_MEM_PAGE_ADD 2
+#define TDH_MEM_SEPT_ADD 3
+#define TDH_VP_ADDCX 4
+#define TDH_MEM_PAGE_RELOCATE 5
+#define TDH_MEM_PAGE_AUG 6
+#define TDH_MEM_RANGE_BLOCK 7
+#define TDH_MNG_KEY_CONFIG 8
+#define TDH_MNG_CREATE 9
+#define TDH_VP_CREATE 10
+#define TDH_MNG_RD 11
+#define TDH_MR_EXTEND 16
+#define TDH_MR_FINALIZE 17
+#define TDH_VP_FLUSH 18
+#define TDH_MNG_VPFLUSHDONE 19
+#define TDH_MNG_KEY_FREEID 20
+#define TDH_MNG_INIT 21
+#define TDH_VP_INIT 22
+#define TDH_VP_RD 26
+#define TDH_MNG_KEY_RECLAIMID 27
+#define TDH_PHYMEM_PAGE_RECLAIM 28
+#define TDH_MEM_PAGE_REMOVE 29
+#define TDH_MEM_SEPT_REMOVE 30
+#define TDH_MEM_TRACK 38
+#define TDH_MEM_RANGE_UNBLOCK 39
+#define TDH_PHYMEM_CACHE_WB 40
+#define TDH_PHYMEM_PAGE_WBINVD 41
+#define TDH_VP_WR 43
+#define TDH_SYS_LP_SHUTDOWN 44
+
+#define TDG_VP_VMCALL_GET_TD_VM_CALL_INFO 0x10000
+#define TDG_VP_VMCALL_MAP_GPA 0x10001
+#define TDG_VP_VMCALL_GET_QUOTE 0x10002
+#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
+#define TDG_VP_VMCALL_SETUP_EVENT_NOTIFY_INTERRUPT 0x10004
+
+/* TDX control structure (TDR/TDCS/TDVPS) field access codes */
+#define TDX_NON_ARCH BIT_ULL(63)
+#define TDX_CLASS_SHIFT 56
+#define TDX_FIELD_MASK GENMASK_ULL(31, 0)
+
+#define __BUILD_TDX_FIELD(non_arch, class, field) \
+ (((non_arch) ? TDX_NON_ARCH : 0) | \
+ ((u64)(class) << TDX_CLASS_SHIFT) | \
+ ((u64)(field) & TDX_FIELD_MASK))
+
+#define BUILD_TDX_FIELD(class, field) \
+ __BUILD_TDX_FIELD(false, (class), (field))
+
+#define BUILD_TDX_FIELD_NON_ARCH(class, field) \
+ __BUILD_TDX_FIELD(true, (class), (field))
+
+
+/* Class code for TD */
+#define TD_CLASS_EXECUTION_CONTROLS 17ULL
+
+/* Class code for TDVPS */
+#define TDVPS_CLASS_VMCS 0ULL
+#define TDVPS_CLASS_GUEST_GPR 16ULL
+#define TDVPS_CLASS_OTHER_GUEST 17ULL
+#define TDVPS_CLASS_MANAGEMENT 32ULL
+
+enum tdx_tdcs_execution_control {
+ TD_TDCS_EXEC_TSC_OFFSET = 10,
+};
+
+/* @field is any of enum tdx_tdcs_execution_control */
+#define TDCS_EXEC(field) BUILD_TDX_FIELD(TD_CLASS_EXECUTION_CONTROLS, (field))
+
+/* @field is the VMCS field encoding */
+#define TDVPS_VMCS(field) BUILD_TDX_FIELD(TDVPS_CLASS_VMCS, (field))
+
+enum tdx_vcpu_guest_other_state {
+ TD_VCPU_STATE_DETAILS_NON_ARCH = 0x100,
+};
+
+union tdx_vcpu_state_details {
+ struct {
+ u64 vmxip : 1;
+ u64 reserved : 63;
+ };
+ u64 full;
+};
+
+/* @field is any of enum tdx_guest_other_state */
+#define TDVPS_STATE(field) BUILD_TDX_FIELD(TDVPS_CLASS_OTHER_GUEST, (field))
+#define TDVPS_STATE_NON_ARCH(field) BUILD_TDX_FIELD_NON_ARCH(TDVPS_CLASS_OTHER_GUEST, (field))
+
+/* Management class fields */
+enum tdx_vcpu_guest_management {
+ TD_VCPU_PEND_NMI = 11,
+};
+
+/* @field is any of enum tdx_vcpu_guest_management */
+#define TDVPS_MANAGEMENT(field) BUILD_TDX_FIELD(TDVPS_CLASS_MANAGEMENT, (field))
+
+#define TDX_EXTENDMR_CHUNKSIZE 256
+
+struct tdx_cpuid_value {
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+ u32 edx;
+} __packed;
+
+#define TDX_TD_ATTRIBUTE_DEBUG BIT_ULL(0)
+#define TDX_TD_ATTRIBUTE_PKS BIT_ULL(30)
+#define TDX_TD_ATTRIBUTE_KL BIT_ULL(31)
+#define TDX_TD_ATTRIBUTE_PERFMON BIT_ULL(63)
+
+/*
+ * TD_PARAMS is provided as an input to TDH_MNG_INIT, the size of which is 1024B.
+ */
+#define TDX_MAX_VCPUS (~(u16)0)
+
+struct td_params {
+ u64 attributes;
+ u64 xfam;
+ u16 max_vcpus;
+ u8 reserved0[6];
+
+ u64 eptp_controls;
+ u64 exec_controls;
+ u16 tsc_frequency;
+ u8 reserved1[38];
+
+ u64 mrconfigid[6];
+ u64 mrowner[6];
+ u64 mrownerconfig[6];
+ u64 reserved2[4];
+
+ union {
+ struct tdx_cpuid_value cpuid_values[0];
+ u8 reserved3[768];
+ };
+} __packed __aligned(1024);
+
+/*
+ * Guest uses MAX_PA for GPAW when set.
+ * 0: GPA.SHARED bit is GPA[47]
+ * 1: GPA.SHARED bit is GPA[51]
+ */
+#define TDX_EXEC_CONTROL_MAX_GPAW BIT_ULL(0)
+
+/*
+ * TDX requires the frequency to be defined in units of 25MHz, which is the
+ * frequency of the core crystal clock on TDX-capable platforms, i.e. the TDX
+ * module can only program frequencies that are multiples of 25MHz. The
+ * frequency must be between 100mhz and 10ghz (inclusive).
+ */
+#define TDX_TSC_KHZ_TO_25MHZ(tsc_in_khz) ((tsc_in_khz) / (25 * 1000))
+#define TDX_TSC_25MHZ_TO_KHZ(tsc_in_25mhz) ((tsc_in_25mhz) * (25 * 1000))
+#define TDX_MIN_TSC_FREQUENCY_KHZ (100 * 1000)
+#define TDX_MAX_TSC_FREQUENCY_KHZ (10 * 1000 * 1000)
+
+#endif /* __KVM_X86_TDX_ARCH_H */
--
2.25.1
From: Sean Christopherson <[email protected]>
Add error codes for the TDX SEAMCALLs both for TDX VMM side for TDH
SEAMCALL and TDX guest side for TDG.VP.VMCALL. KVM issues the TDX
SEAMCALLs and checks its error code. KVM handles hypercall from the TDX
guest and may return an error. So error code for the TDX guest is also
needed.
TDX SEAMCALL uses bits 31:0 to return more information, so these error
codes will only exactly match RAX[63:32]. Error codes for TDG.VP.VMCALL is
defined by TDX Guest-Host-Communication interface spec.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx_errno.h | 38 ++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
create mode 100644 arch/x86/kvm/vmx/tdx_errno.h
diff --git a/arch/x86/kvm/vmx/tdx_errno.h b/arch/x86/kvm/vmx/tdx_errno.h
new file mode 100644
index 000000000000..389b1b53da25
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx_errno.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* architectural status code for SEAMCALL */
+
+#ifndef __KVM_X86_TDX_ERRNO_H
+#define __KVM_X86_TDX_ERRNO_H
+
+#define TDX_SEAMCALL_STATUS_MASK 0xFFFFFFFF00000000ULL
+
+/*
+ * TDX SEAMCALL Status Codes (returned in RAX)
+ */
+#define TDX_SUCCESS 0x0000000000000000ULL
+#define TDX_NON_RECOVERABLE_VCPU 0x4000000100000000ULL
+#define TDX_INTERRUPTED_RESUMABLE 0x8000000300000000ULL
+#define TDX_OPERAND_BUSY 0x8000020000000000ULL
+#define TDX_VCPU_NOT_ASSOCIATED 0x8000070200000000ULL
+#define TDX_KEY_GENERATION_FAILED 0x8000080000000000ULL
+#define TDX_KEY_STATE_INCORRECT 0xC000081100000000ULL
+#define TDX_KEY_CONFIGURED 0x0000081500000000ULL
+#define TDX_NO_HKID_READY_TO_WBCACHE 0x0000082100000000ULL
+#define TDX_EPT_WALK_FAILED 0xC0000B0000000000ULL
+
+/*
+ * TDG.VP.VMCALL Status Codes (returned in R10)
+ */
+#define TDG_VP_VMCALL_SUCCESS 0x0000000000000000ULL
+#define TDG_VP_VMCALL_RETRY 0x0000000000000001ULL
+#define TDG_VP_VMCALL_INVALID_OPERAND 0x8000000000000000ULL
+#define TDG_VP_VMCALL_TDREPORT_FAILED 0x8000000000000001ULL
+
+/*
+ * TDX module operand ID, appears in 31:0 part of error code as
+ * detail information
+ */
+#define TDX_OPERAND_ID_RCX 0x01
+#define TDX_OPERAND_ID_SEPT 0x92
+
+#endif /* __KVM_X86_TDX_ERRNO_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
A VMM interacts with the TDX module using a new instruction (SEAMCALL). A
TDX VMM uses SEAMCALLs where a VMX VMM would have directly interacted with
VMX instructions. For instance, a TDX VMM does not have full access to the
VM control structure corresponding to VMX VMCS. Instead, a VMM induces the
TDX module to act on behalf via SEAMCALLs.
Export __seamcall and define C wrapper functions for SEAMCALLs for
readability.
Some SEAMCALL APIs donates host pages to TDX module or guest TD and the
donated pages are encrypted. Some of such SEAMCALLs flush cache lines
(typically by movdir64b instruction), some don't. Those that doesn't
clear cache lines require the VMM to flush the cache lines to avoid cache
line alias.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/tdx.h | 4 +
arch/x86/kvm/vmx/tdx_ops.h | 202 +++++++++++++++++++++++++++++++
arch/x86/virt/vmx/tdx/seamcall.S | 2 +
arch/x86/virt/vmx/tdx/tdx.h | 3 -
4 files changed, 208 insertions(+), 3 deletions(-)
create mode 100644 arch/x86/kvm/vmx/tdx_ops.h
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 112a5b9bd5cd..6c01ab572c1f 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -104,10 +104,14 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
bool platform_tdx_enabled(void);
int tdx_cpu_enable(void);
int tdx_enable(void);
+u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
+ struct tdx_module_output *out);
#else /* !CONFIG_INTEL_TDX_HOST */
static inline bool platform_tdx_enabled(void) { return false; }
static inline int tdx_cpu_enable(void) { return -EINVAL; }
static inline int tdx_enable(void) { return -EINVAL; }
+static inline u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
+ struct tdx_module_output *out) { return TDX_SEAMCALL_UD; };
#endif /* CONFIG_INTEL_TDX_HOST */
#endif /* !__ASSEMBLY__ */
diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h
new file mode 100644
index 000000000000..70e569838e1c
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx_ops.h
@@ -0,0 +1,202 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* constants/data definitions for TDX SEAMCALLs */
+
+#ifndef __KVM_X86_TDX_OPS_H
+#define __KVM_X86_TDX_OPS_H
+
+#include <linux/compiler.h>
+
+#include <asm/cacheflush.h>
+#include <asm/asm.h>
+#include <asm/kvm_host.h>
+
+#include "tdx_errno.h"
+#include "tdx_arch.h"
+#include "x86.h"
+
+static inline u64 kvm_seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
+ struct tdx_module_output *out)
+{
+ u64 ret;
+
+ ret = __seamcall(op, rcx, rdx, r8, r9, out);
+ if (ret == TDX_SEAMCALL_UD) {
+ /*
+ * TDX requires VMXON or #UD. In the case of reboot or kexec,
+ * VMX is made off (VMXOFF) by kvm reboot notifier,
+ * kvm_reboot(), while TDs are still running. The callers check
+ * the returned error and complain. Suppress it by returning 0.
+ */
+ kvm_spurious_fault();
+ return 0;
+ }
+ return ret;
+}
+
+static inline u64 tdh_mng_addcx(hpa_t tdr, hpa_t addr)
+{
+ clflush_cache_range(__va(addr), PAGE_SIZE);
+ return kvm_seamcall(TDH_MNG_ADDCX, addr, tdr, 0, 0, NULL);
+}
+
+static inline u64 tdh_mem_page_add(hpa_t tdr, gpa_t gpa, hpa_t hpa, hpa_t source,
+ struct tdx_module_output *out)
+{
+ clflush_cache_range(__va(hpa), PAGE_SIZE);
+ return kvm_seamcall(TDH_MEM_PAGE_ADD, gpa, tdr, hpa, source, out);
+}
+
+static inline u64 tdh_mem_sept_add(hpa_t tdr, gpa_t gpa, int level, hpa_t page,
+ struct tdx_module_output *out)
+{
+ clflush_cache_range(__va(page), PAGE_SIZE);
+ return kvm_seamcall(TDH_MEM_SEPT_ADD, gpa | level, tdr, page, 0, out);
+}
+
+static inline u64 tdh_mem_sept_remove(hpa_t tdr, gpa_t gpa, int level,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MEM_SEPT_REMOVE, gpa | level, tdr, 0, 0, out);
+}
+
+static inline u64 tdh_vp_addcx(hpa_t tdvpr, hpa_t addr)
+{
+ clflush_cache_range(__va(addr), PAGE_SIZE);
+ return kvm_seamcall(TDH_VP_ADDCX, addr, tdvpr, 0, 0, NULL);
+}
+
+static inline u64 tdh_mem_page_relocate(hpa_t tdr, gpa_t gpa, hpa_t hpa,
+ struct tdx_module_output *out)
+{
+ clflush_cache_range(__va(hpa), PAGE_SIZE);
+ return kvm_seamcall(TDH_MEM_PAGE_RELOCATE, gpa, tdr, hpa, 0, out);
+}
+
+static inline u64 tdh_mem_page_aug(hpa_t tdr, gpa_t gpa, hpa_t hpa,
+ struct tdx_module_output *out)
+{
+ clflush_cache_range(__va(hpa), PAGE_SIZE);
+ return kvm_seamcall(TDH_MEM_PAGE_AUG, gpa, tdr, hpa, 0, out);
+}
+
+static inline u64 tdh_mem_range_block(hpa_t tdr, gpa_t gpa, int level,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MEM_RANGE_BLOCK, gpa | level, tdr, 0, 0, out);
+}
+
+static inline u64 tdh_mng_key_config(hpa_t tdr)
+{
+ return kvm_seamcall(TDH_MNG_KEY_CONFIG, tdr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_mng_create(hpa_t tdr, int hkid)
+{
+ clflush_cache_range(__va(tdr), PAGE_SIZE);
+ return kvm_seamcall(TDH_MNG_CREATE, tdr, hkid, 0, 0, NULL);
+}
+
+static inline u64 tdh_vp_create(hpa_t tdr, hpa_t tdvpr)
+{
+ clflush_cache_range(__va(tdvpr), PAGE_SIZE);
+ return kvm_seamcall(TDH_VP_CREATE, tdvpr, tdr, 0, 0, NULL);
+}
+
+static inline u64 tdh_mng_rd(hpa_t tdr, u64 field, struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MNG_RD, tdr, field, 0, 0, out);
+}
+
+static inline u64 tdh_mr_extend(hpa_t tdr, gpa_t gpa,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MR_EXTEND, gpa, tdr, 0, 0, out);
+}
+
+static inline u64 tdh_mr_finalize(hpa_t tdr)
+{
+ return kvm_seamcall(TDH_MR_FINALIZE, tdr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_vp_flush(hpa_t tdvpr)
+{
+ return kvm_seamcall(TDH_VP_FLUSH, tdvpr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_mng_vpflushdone(hpa_t tdr)
+{
+ return kvm_seamcall(TDH_MNG_VPFLUSHDONE, tdr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_mng_key_freeid(hpa_t tdr)
+{
+ return kvm_seamcall(TDH_MNG_KEY_FREEID, tdr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_mng_init(hpa_t tdr, hpa_t td_params,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MNG_INIT, tdr, td_params, 0, 0, out);
+}
+
+static inline u64 tdh_vp_init(hpa_t tdvpr, u64 rcx)
+{
+ return kvm_seamcall(TDH_VP_INIT, tdvpr, rcx, 0, 0, NULL);
+}
+
+static inline u64 tdh_vp_rd(hpa_t tdvpr, u64 field,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_VP_RD, tdvpr, field, 0, 0, out);
+}
+
+static inline u64 tdh_mng_key_reclaimid(hpa_t tdr)
+{
+ return kvm_seamcall(TDH_MNG_KEY_RECLAIMID, tdr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_phymem_page_reclaim(hpa_t page,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_PHYMEM_PAGE_RECLAIM, page, 0, 0, 0, out);
+}
+
+static inline u64 tdh_mem_page_remove(hpa_t tdr, gpa_t gpa, int level,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MEM_PAGE_REMOVE, gpa | level, tdr, 0, 0, out);
+}
+
+static inline u64 tdh_sys_lp_shutdown(void)
+{
+ return kvm_seamcall(TDH_SYS_LP_SHUTDOWN, 0, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_mem_track(hpa_t tdr)
+{
+ return kvm_seamcall(TDH_MEM_TRACK, tdr, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_mem_range_unblock(hpa_t tdr, gpa_t gpa, int level,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_MEM_RANGE_UNBLOCK, gpa | level, tdr, 0, 0, out);
+}
+
+static inline u64 tdh_phymem_cache_wb(bool resume)
+{
+ return kvm_seamcall(TDH_PHYMEM_CACHE_WB, resume ? 1 : 0, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_phymem_page_wbinvd(hpa_t page)
+{
+ return kvm_seamcall(TDH_PHYMEM_PAGE_WBINVD, page, 0, 0, 0, NULL);
+}
+
+static inline u64 tdh_vp_wr(hpa_t tdvpr, u64 field, u64 val, u64 mask,
+ struct tdx_module_output *out)
+{
+ return kvm_seamcall(TDH_VP_WR, tdvpr, field, val, mask, out);
+}
+
+#endif /* __KVM_X86_TDX_OPS_H */
diff --git a/arch/x86/virt/vmx/tdx/seamcall.S b/arch/x86/virt/vmx/tdx/seamcall.S
index f81be6b9c133..b90a7fe05494 100644
--- a/arch/x86/virt/vmx/tdx/seamcall.S
+++ b/arch/x86/virt/vmx/tdx/seamcall.S
@@ -1,5 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/linkage.h>
+#include <asm/export.h>
#include <asm/frame.h>
#include "tdxcall.S"
@@ -50,3 +51,4 @@ SYM_FUNC_START(__seamcall)
FRAME_END
RET
SYM_FUNC_END(__seamcall)
+EXPORT_SYMBOL_GPL(__seamcall)
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 48f830087e7e..4e497f202586 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -144,7 +144,4 @@ struct tdmr_info_list {
int max_tdmrs; /* How many 'tdmr_info's are allocated */
};
-struct tdx_module_output;
-u64 __seamcall(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
- struct tdx_module_output *out);
#endif
--
2.25.1
From: Isaku Yamahata <[email protected]>
Add helper functions to print out errors from the TDX module in a uniform
manner.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/Makefile | 2 +-
arch/x86/kvm/vmx/tdx_error.c | 21 +++++++++++++++++++++
arch/x86/kvm/vmx/tdx_ops.h | 5 +++++
3 files changed, 27 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/kvm/vmx/tdx_error.c
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 4b01ab842ab7..e3354b784e10 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -25,7 +25,7 @@ kvm-$(CONFIG_KVM_SMM) += smm.o
kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
vmx/hyperv.o vmx/nested.o vmx/posted_intr.o vmx/main.o
kvm-intel-$(CONFIG_X86_SGX_KVM) += vmx/sgx.o
-kvm-intel-$(CONFIG_INTEL_TDX_HOST) += vmx/tdx.o
+kvm-intel-$(CONFIG_INTEL_TDX_HOST) += vmx/tdx.o vmx/tdx_error.o
kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o \
svm/sev.o svm/hyperv.o
diff --git a/arch/x86/kvm/vmx/tdx_error.c b/arch/x86/kvm/vmx/tdx_error.c
new file mode 100644
index 000000000000..574b72d34e1e
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx_error.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/* functions to record TDX SEAMCALL error */
+
+#include <linux/kernel.h>
+#include <linux/bug.h>
+
+#include "tdx_ops.h"
+
+void pr_tdx_error(u64 op, u64 error_code, const struct tdx_module_output *out)
+{
+ if (!out) {
+ pr_err_ratelimited("SEAMCALL[%lld] failed: 0x%llx\n",
+ op, error_code);
+ return;
+ }
+
+ pr_err_ratelimited("SEAMCALL[%lld] failed: 0x%llx RCX 0x%llx, RDX 0x%llx,"
+ " R8 0x%llx, R9 0x%llx, R10 0x%llx, R11 0x%llx\n",
+ op, error_code,
+ out->rcx, out->rdx, out->r8, out->r9, out->r10, out->r11);
+}
diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h
index 70e569838e1c..177f444ebbb3 100644
--- a/arch/x86/kvm/vmx/tdx_ops.h
+++ b/arch/x86/kvm/vmx/tdx_ops.h
@@ -9,6 +9,7 @@
#include <asm/cacheflush.h>
#include <asm/asm.h>
#include <asm/kvm_host.h>
+#include <asm/tdx.h>
#include "tdx_errno.h"
#include "tdx_arch.h"
@@ -33,6 +34,10 @@ static inline u64 kvm_seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
return ret;
}
+#ifdef CONFIG_INTEL_TDX_HOST
+void pr_tdx_error(u64 op, u64 error_code, const struct tdx_module_output *out);
+#endif
+
static inline u64 tdh_mng_addcx(hpa_t tdr, hpa_t addr)
{
clflush_cache_range(__va(addr), PAGE_SIZE);
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TD VM
creation/destruction.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index f11ea701dc19..098150da6ea2 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -16,8 +16,8 @@ Patch Layer status
Patch layer Status
* TDX, VMX coexistence: Applied
-* TDX architectural definitions: Applying
-* TD VM creation/destruction: Not yet
+* TDX architectural definitions: Applied
+* TD VM creation/destruction: Applying
* TD vcpu creation/destruction: Not yet
* TDX EPT violation: Not yet
* TD finalization: Not yet
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX private host key id (HKID) is assigned to guest TD. The memory
controller encrypts guest TD memory with the assigned TDX HKID. Add helper
functions to allocate/free TDX private HKID so that TDX KVM can manage it.
Also export the global TDX private HKID that is used to encrypt TDX module,
its memory and some dynamic data (TDR). When VMM releasing encrypted page
to reuse it, the page needs to be flushed with the used HKID. VMM needs
the global TDX private HKID to flush such pages.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/tdx.h | 12 ++++++++++++
arch/x86/virt/vmx/tdx/tdx.c | 34 +++++++++++++++++++++++++++++++++-
2 files changed, 45 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 6c01ab572c1f..7d99a48a98cc 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -104,6 +104,16 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
bool platform_tdx_enabled(void);
int tdx_cpu_enable(void);
int tdx_enable(void);
+/*
+ * Key id globally used by TDX module: TDX module maps TDR with this TDX global
+ * key id. TDR includes key id assigned to the TD. Then TDX module maps other
+ * TD-related pages with the assigned key id. TDR requires this TDX global key
+ * id for cache flush unlike other TD-related pages.
+ */
+extern u32 tdx_global_keyid __ro_after_init;
+int tdx_guest_keyid_alloc(void);
+void tdx_guest_keyid_free(int keyid);
+
u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
struct tdx_module_output *out);
#else /* !CONFIG_INTEL_TDX_HOST */
@@ -112,6 +122,8 @@ static inline int tdx_cpu_enable(void) { return -EINVAL; }
static inline int tdx_enable(void) { return -EINVAL; }
static inline u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
struct tdx_module_output *out) { return TDX_SEAMCALL_UD; };
+static inline int tdx_guest_keyid_alloc(void) { return -EOPNOTSUPP; }
+static inline void tdx_guest_keyid_free(int keyid) { }
#endif /* CONFIG_INTEL_TDX_HOST */
#endif /* !__ASSEMBLY__ */
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index ee94a7327d93..3251fdf74667 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -33,7 +33,8 @@
#include <asm/tdx.h>
#include "tdx.h"
-static u32 tdx_global_keyid __ro_after_init;
+u32 tdx_global_keyid __ro_after_init;
+EXPORT_SYMBOL_GPL(tdx_global_keyid);
static u32 tdx_guest_keyid_start __ro_after_init;
static u32 tdx_nr_guest_keyids __ro_after_init;
@@ -138,6 +139,31 @@ static struct notifier_block tdx_memory_nb = {
.notifier_call = tdx_memory_notifier,
};
+/* TDX KeyID pool */
+static DEFINE_IDA(tdx_guest_keyid_pool);
+
+int tdx_guest_keyid_alloc(void)
+{
+ if (WARN_ON_ONCE(!tdx_guest_keyid_start || !tdx_nr_guest_keyids))
+ return -EINVAL;
+
+ /* The first keyID is reserved for the global key. */
+ return ida_alloc_range(&tdx_guest_keyid_pool, tdx_guest_keyid_start + 1,
+ tdx_guest_keyid_start + tdx_nr_guest_keyids - 1,
+ GFP_KERNEL);
+}
+EXPORT_SYMBOL_GPL(tdx_guest_keyid_alloc);
+
+void tdx_guest_keyid_free(int keyid)
+{
+ /* keyid = 0 is reserved. */
+ if (WARN_ON_ONCE(keyid <= 0))
+ return;
+
+ ida_free(&tdx_guest_keyid_pool, keyid);
+}
+EXPORT_SYMBOL_GPL(tdx_guest_keyid_free);
+
static int __init tdx_init(void)
{
u32 tdx_keyid_start, nr_tdx_keyids;
@@ -1218,6 +1244,12 @@ static int init_tdx_module(void)
if (ret)
goto out_free_pamts;
+ /*
+ * Reserve the first TDX KeyID as global KeyID to protect
+ * TDX module metadata.
+ */
+ tdx_global_keyid = tdx_keyid_start;
+
/* Initialize TDMRs to complete the TDX module initialization */
ret = init_tdmrs(&tdmr_list);
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX KVM needs system-wide information about the TDX module, struct
tdsysinfo_struct. Add a helper function tdx_get_sysinfo() to return it
instead of KVM getting it with various error checks. Make KVM call the
function and stash the info. Move out the struct definition about it to
common place arch/x86/include/asm/tdx.h.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/tdx.h | 54 +++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.c | 15 ++++++++++-
arch/x86/virt/vmx/tdx/tdx.c | 21 ++++++++++++---
arch/x86/virt/vmx/tdx/tdx.h | 51 -----------------------------------
4 files changed, 85 insertions(+), 56 deletions(-)
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 7d99a48a98cc..05870e5ed131 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -101,6 +101,58 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
#endif /* CONFIG_INTEL_TDX_GUEST && CONFIG_KVM_GUEST */
#ifdef CONFIG_INTEL_TDX_HOST
+struct tdx_cpuid_config {
+ u32 leaf;
+ u32 sub_leaf;
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+ u32 edx;
+} __packed;
+
+#define TDSYSINFO_STRUCT_SIZE 1024
+#define TDSYSINFO_STRUCT_ALIGNMENT 1024
+
+/*
+ * The size of this structure itself is flexible. The actual structure
+ * passed to TDH.SYS.INFO must be padded to TDSYSINFO_STRUCT_SIZE and be
+ * aligned to TDSYSINFO_STRUCT_ALIGNMENT using DECLARE_PADDED_STRUCT().
+ */
+struct tdsysinfo_struct {
+ /* TDX-SEAM Module Info */
+ u32 attributes;
+ u32 vendor_id;
+ u32 build_date;
+ u16 build_num;
+ u16 minor_version;
+ u16 major_version;
+ u8 reserved0[14];
+ /* Memory Info */
+ u16 max_tdmrs;
+ u16 max_reserved_per_tdmr;
+ u16 pamt_entry_size;
+ u8 reserved1[10];
+ /* Control Struct Info */
+ u16 tdcs_base_size;
+ u8 reserved2[2];
+ u16 tdvps_base_size;
+ u8 tdvps_xfam_dependent_size;
+ u8 reserved3[9];
+ /* TD Capabilities */
+ u64 attributes_fixed0;
+ u64 attributes_fixed1;
+ u64 xfam_fixed0;
+ u64 xfam_fixed1;
+ u8 reserved4[32];
+ u32 num_cpuid_config;
+ /*
+ * The actual number of CPUID_CONFIG depends on above
+ * 'num_cpuid_config'.
+ */
+ DECLARE_FLEX_ARRAY(struct tdx_cpuid_config, cpuid_configs);
+} __packed;
+
+const struct tdsysinfo_struct *tdx_get_sysinfo(void);
bool platform_tdx_enabled(void);
int tdx_cpu_enable(void);
int tdx_enable(void);
@@ -117,6 +169,8 @@ void tdx_guest_keyid_free(int keyid);
u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
struct tdx_module_output *out);
#else /* !CONFIG_INTEL_TDX_HOST */
+struct tdsysinfo_struct;
+static inline const struct tdsysinfo_struct *tdx_get_sysinfo(void) { return NULL; }
static inline bool platform_tdx_enabled(void) { return false; }
static inline int tdx_cpu_enable(void) { return -EINVAL; }
static inline int tdx_enable(void) { return -EINVAL; }
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 36738904c26a..e9b7aa5654e9 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -11,6 +11,11 @@
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#define TDX_MAX_NR_CPUID_CONFIGS \
+ ((TDSYSINFO_STRUCT_SIZE - \
+ offsetof(struct tdsysinfo_struct, cpuid_configs)) \
+ / sizeof(struct tdx_cpuid_config))
+
int tdx_hardware_enable(void)
{
return tdx_cpu_enable();
@@ -18,7 +23,11 @@ int tdx_hardware_enable(void)
static int __init tdx_module_setup(void)
{
- int ret;
+ const struct tdsysinfo_struct *tdsysinfo;
+ int ret = 0;
+
+ BUILD_BUG_ON(sizeof(*tdsysinfo) > TDSYSINFO_STRUCT_SIZE);
+ BUILD_BUG_ON(TDX_MAX_NR_CPUID_CONFIGS != 37);
ret = tdx_enable();
if (ret) {
@@ -26,6 +35,10 @@ static int __init tdx_module_setup(void)
return ret;
}
+ /* Sanitary check just in case. */
+ tdsysinfo = tdx_get_sysinfo();
+ WARN_ON(tdsysinfo->num_cpuid_config > TDX_MAX_NR_CPUID_CONFIGS);
+
pr_info("TDX is supported.\n");
return 0;
}
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 3251fdf74667..f9f9c1b76501 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -385,7 +385,7 @@ static void print_cmrs(struct cmr_info *cmr_array, int nr_cmrs)
* CMRs, and save them to @sysinfo and @cmr_array. @sysinfo must have
* been padded to have enough room to save the TDSYSINFO_STRUCT.
*/
-static int tdx_get_sysinfo(struct tdsysinfo_struct *sysinfo,
+static int __tdx_get_sysinfo(struct tdsysinfo_struct *sysinfo,
struct cmr_info *cmr_array)
{
struct tdx_module_output out;
@@ -410,6 +410,21 @@ static int tdx_get_sysinfo(struct tdsysinfo_struct *sysinfo,
return 0;
}
+static DECLARE_PADDED_STRUCT(tdsysinfo_struct, tdsysinfo,
+ TDSYSINFO_STRUCT_SIZE, TDSYSINFO_STRUCT_ALIGNMENT);
+
+const struct tdsysinfo_struct *tdx_get_sysinfo(void)
+{
+ const struct tdsysinfo_struct *r = NULL;
+
+ mutex_lock(&tdx_module_lock);
+ if (tdx_module_status == TDX_MODULE_INITIALIZED)
+ r = &PADDED_STRUCT(tdsysinfo);
+ mutex_unlock(&tdx_module_lock);
+ return r;
+}
+EXPORT_SYMBOL_GPL(tdx_get_sysinfo);
+
/*
* Add a memory region as a TDX memory block. The caller must make sure
* all memory regions are added in address ascending order and don't
@@ -1186,15 +1201,13 @@ static int init_tdmrs(struct tdmr_info_list *tdmr_list)
static int init_tdx_module(void)
{
- static DECLARE_PADDED_STRUCT(tdsysinfo_struct, tdsysinfo,
- TDSYSINFO_STRUCT_SIZE, TDSYSINFO_STRUCT_ALIGNMENT);
static struct cmr_info cmr_array[MAX_CMRS]
__aligned(CMR_INFO_ARRAY_ALIGNMENT);
struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
struct tdmr_info_list tdmr_list;
int ret;
- ret = tdx_get_sysinfo(sysinfo, cmr_array);
+ ret = __tdx_get_sysinfo(sysinfo, cmr_array);
if (ret)
return ret;
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 4e497f202586..db0cbcceb5b3 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -31,15 +31,6 @@ struct cmr_info {
#define MAX_CMRS 32
#define CMR_INFO_ARRAY_ALIGNMENT 512
-struct cpuid_config {
- u32 leaf;
- u32 sub_leaf;
- u32 eax;
- u32 ebx;
- u32 ecx;
- u32 edx;
-} __packed;
-
#define DECLARE_PADDED_STRUCT(type, name, size, alignment) \
struct type##_padded { \
union { \
@@ -50,48 +41,6 @@ struct cpuid_config {
#define PADDED_STRUCT(name) (name##_padded.name)
-#define TDSYSINFO_STRUCT_SIZE 1024
-#define TDSYSINFO_STRUCT_ALIGNMENT 1024
-
-/*
- * The size of this structure itself is flexible. The actual structure
- * passed to TDH.SYS.INFO must be padded to TDSYSINFO_STRUCT_SIZE and be
- * aligned to TDSYSINFO_STRUCT_ALIGNMENT using DECLARE_PADDED_STRUCT().
- */
-struct tdsysinfo_struct {
- /* TDX-SEAM Module Info */
- u32 attributes;
- u32 vendor_id;
- u32 build_date;
- u16 build_num;
- u16 minor_version;
- u16 major_version;
- u8 reserved0[14];
- /* Memory Info */
- u16 max_tdmrs;
- u16 max_reserved_per_tdmr;
- u16 pamt_entry_size;
- u8 reserved1[10];
- /* Control Struct Info */
- u16 tdcs_base_size;
- u8 reserved2[2];
- u16 tdvps_base_size;
- u8 tdvps_xfam_dependent_size;
- u8 reserved3[9];
- /* TD Capabilities */
- u64 attributes_fixed0;
- u64 attributes_fixed1;
- u64 xfam_fixed0;
- u64 xfam_fixed1;
- u8 reserved4[32];
- u32 num_cpuid_config;
- /*
- * The actual number of CPUID_CONFIG depends on above
- * 'num_cpuid_config'.
- */
- DECLARE_FLEX_ARRAY(struct cpuid_config, cpuid_configs);
-} __packed;
-
struct tdmr_reserved_area {
u64 offset;
u64 size;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Add a place holder function for TDX specific VM-scoped ioctl as mem_enc_op.
TDX specific sub-commands will be added to retrieve/pass TDX specific
parameters. Make mem_enc_ioctl non-optional as it's not optional now.
KVM_MEMORY_ENCRYPT_OP was introduced for VM-scoped operations specific for
guest state-protected VM. It defined subcommands for technology-specific
operations under KVM_MEMORY_ENCRYPT_OP. Despite its name, the subcommands
are not limited to memory encryption, but various technology-specific
operations are defined. It's natural to repurpose KVM_MEMORY_ENCRYPT_OP
for TDX specific operations and define subcommands.
TDX requires VM-scoped TDX-specific operations for device model, for
example, qemu. Getting system-wide parameters, TDX-specific VM
initialization.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 2 +-
arch/x86/kvm/vmx/main.c | 9 +++++++++
arch/x86/kvm/vmx/tdx.c | 26 ++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 4 ++++
arch/x86/kvm/x86.c | 4 ----
5 files changed, 40 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index b46dcac078b2..58fbaa05fc8c 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -117,7 +117,7 @@ KVM_X86_OP(enter_smm)
KVM_X86_OP(leave_smm)
KVM_X86_OP(enable_smi_window)
#endif
-KVM_X86_OP_OPTIONAL(dev_mem_enc_ioctl)
+KVM_X86_OP(dev_mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_register_region)
KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 6a5d0c7a2950..8ddd263eeabc 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -50,6 +50,14 @@ static int vt_vm_init(struct kvm *kvm)
return vmx_vm_init(kvm);
}
+static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
+{
+ if (!is_td(kvm))
+ return -ENOTTY;
+
+ return tdx_vm_ioctl(kvm, argp);
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
( \
BIT(APICV_INHIBIT_REASON_DISABLE)| \
@@ -203,6 +211,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
.dev_mem_enc_ioctl = tdx_dev_ioctl,
+ .mem_enc_ioctl = vt_mem_enc_ioctl,
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index b59d3081d061..d759028a698e 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -72,6 +72,32 @@ int tdx_dev_ioctl(void __user *argp)
return 0;
}
+int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
+{
+ struct kvm_tdx_cmd tdx_cmd;
+ int r;
+
+ if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd)))
+ return -EFAULT;
+ if (tdx_cmd.error || tdx_cmd.unused)
+ return -EINVAL;
+
+ mutex_lock(&kvm->lock);
+
+ switch (tdx_cmd.id) {
+ default:
+ r = -EINVAL;
+ goto out;
+ }
+
+ if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd)))
+ r = -EFAULT;
+
+out:
+ mutex_unlock(&kvm->lock);
+ return r;
+}
+
static int __init tdx_module_setup(void)
{
const struct tdsysinfo_struct *tdsysinfo;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 78c5537e23a1..c70749114e9e 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -142,11 +142,15 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
int tdx_hardware_enable(void);
bool tdx_is_vm_type_supported(unsigned long type);
int tdx_dev_ioctl(void __user *argp);
+
+int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
+
+static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a3dc32e33aca..8687623929c3 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6978,10 +6978,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
goto out;
}
case KVM_MEMORY_ENCRYPT_OP: {
- r = -ENOTTY;
- if (!kvm_x86_ops.mem_enc_ioctl)
- goto out;
-
r = static_call(kvm_x86_mem_enc_ioctl)(kvm, argp);
break;
}
--
2.25.1
From: Sean Christopherson <[email protected]>
Implement a system-scoped ioctl to get system-wide parameters for TDX.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++
arch/x86/kvm/vmx/main.c | 2 ++
arch/x86/kvm/vmx/tdx.c | 51 +++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 2 ++
arch/x86/kvm/x86.c | 6 ++++
tools/arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++
8 files changed, 159 insertions(+)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index eac4b65d1b01..b46dcac078b2 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -117,6 +117,7 @@ KVM_X86_OP(enter_smm)
KVM_X86_OP(leave_smm)
KVM_X86_OP(enable_smi_window)
#endif
+KVM_X86_OP_OPTIONAL(dev_mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_register_region)
KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 00c25f6ab871..49e3ca89aced 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1719,6 +1719,7 @@ struct kvm_x86_ops {
void (*enable_smi_window)(struct kvm_vcpu *vcpu);
#endif
+ int (*dev_mem_enc_ioctl)(void __user *argp);
int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
int (*mem_enc_unregister_region)(struct kvm *kvm, struct kvm_enc_region *argp);
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 6afbfbb32d56..af4c5bd0af1c 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -562,4 +562,52 @@ struct kvm_pmu_event_filter {
#define KVM_X86_DEFAULT_VM 0
#define KVM_X86_PROTECTED_VM 1
+/* Trust Domain eXtension sub-ioctl() commands. */
+enum kvm_tdx_cmd_id {
+ KVM_TDX_CAPABILITIES = 0,
+
+ KVM_TDX_CMD_NR_MAX,
+};
+
+struct kvm_tdx_cmd {
+ /* enum kvm_tdx_cmd_id */
+ __u32 id;
+ /* flags for sub-commend. If sub-command doesn't use this, set zero. */
+ __u32 flags;
+ /*
+ * data for each sub-command. An immediate or a pointer to the actual
+ * data in process virtual address. If sub-command doesn't use it,
+ * set zero.
+ */
+ __u64 data;
+ /*
+ * Auxiliary error code. The sub-command may return TDX SEAMCALL
+ * status code in addition to -Exxx.
+ * Defined for consistency with struct kvm_sev_cmd.
+ */
+ __u64 error;
+ /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
+ __u64 unused;
+};
+
+struct kvm_tdx_cpuid_config {
+ __u32 leaf;
+ __u32 sub_leaf;
+ __u32 eax;
+ __u32 ebx;
+ __u32 ecx;
+ __u32 edx;
+};
+
+struct kvm_tdx_capabilities {
+ __u64 attrs_fixed0;
+ __u64 attrs_fixed1;
+ __u64 xfam_fixed0;
+ __u64 xfam_fixed1;
+
+ __u32 nr_cpuid_configs;
+ __u32 padding;
+ struct kvm_tdx_cpuid_config cpuid_configs[0];
+};
+
#endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index c8548004802a..6a5d0c7a2950 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -201,6 +201,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.complete_emulated_msr = kvm_complete_insn_gp,
.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
+
+ .dev_mem_enc_ioctl = tdx_dev_ioctl,
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index e9b7aa5654e9..b59d3081d061 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -21,6 +21,57 @@ int tdx_hardware_enable(void)
return tdx_cpu_enable();
}
+int tdx_dev_ioctl(void __user *argp)
+{
+ struct kvm_tdx_capabilities __user *user_caps;
+ const struct tdsysinfo_struct *tdsysinfo;
+ struct kvm_tdx_capabilities caps;
+ struct kvm_tdx_cmd cmd;
+
+ BUILD_BUG_ON(sizeof(struct kvm_tdx_cpuid_config) !=
+ sizeof(struct tdx_cpuid_config));
+
+ if (copy_from_user(&cmd, argp, sizeof(cmd)))
+ return -EFAULT;
+ if (cmd.flags || cmd.error || cmd.unused)
+ return -EINVAL;
+ /*
+ * Currently only KVM_TDX_CAPABILITIES is defined for system-scoped
+ * mem_enc_ioctl().
+ */
+ if (cmd.id != KVM_TDX_CAPABILITIES)
+ return -EINVAL;
+
+ tdsysinfo = tdx_get_sysinfo();
+ if (!tdsysinfo)
+ return -ENOTSUPP;
+
+ user_caps = (void __user *)cmd.data;
+ if (copy_from_user(&caps, user_caps, sizeof(caps)))
+ return -EFAULT;
+
+ if (caps.nr_cpuid_configs < tdsysinfo->num_cpuid_config)
+ return -E2BIG;
+
+ caps = (struct kvm_tdx_capabilities) {
+ .attrs_fixed0 = tdsysinfo->attributes_fixed0,
+ .attrs_fixed1 = tdsysinfo->attributes_fixed1,
+ .xfam_fixed0 = tdsysinfo->xfam_fixed0,
+ .xfam_fixed1 = tdsysinfo->xfam_fixed1,
+ .nr_cpuid_configs = tdsysinfo->num_cpuid_config,
+ .padding = 0,
+ };
+
+ if (copy_to_user(user_caps, &caps, sizeof(caps)))
+ return -EFAULT;
+ if (copy_to_user(user_caps->cpuid_configs, &tdsysinfo->cpuid_configs,
+ tdsysinfo->num_cpuid_config *
+ sizeof(struct tdx_cpuid_config)))
+ return -EFAULT;
+
+ return 0;
+}
+
static int __init tdx_module_setup(void)
{
const struct tdsysinfo_struct *tdsysinfo;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index b2c74c1b5bbd..78c5537e23a1 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -141,10 +141,12 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
int tdx_hardware_enable(void);
bool tdx_is_vm_type_supported(unsigned long type);
+int tdx_dev_ioctl(void __user *argp);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
+static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 27ab684f8374..a3dc32e33aca 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4718,6 +4718,12 @@ long kvm_arch_dev_ioctl(struct file *filp,
r = kvm_x86_dev_has_attr(&attr);
break;
}
+ case KVM_MEMORY_ENCRYPT_OP:
+ r = -EINVAL;
+ if (!kvm_x86_ops.dev_mem_enc_ioctl)
+ goto out;
+ r = static_call(kvm_x86_dev_mem_enc_ioctl)(argp);
+ break;
default:
r = -EINVAL;
break;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 6afbfbb32d56..af4c5bd0af1c 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -562,4 +562,52 @@ struct kvm_pmu_event_filter {
#define KVM_X86_DEFAULT_VM 0
#define KVM_X86_PROTECTED_VM 1
+/* Trust Domain eXtension sub-ioctl() commands. */
+enum kvm_tdx_cmd_id {
+ KVM_TDX_CAPABILITIES = 0,
+
+ KVM_TDX_CMD_NR_MAX,
+};
+
+struct kvm_tdx_cmd {
+ /* enum kvm_tdx_cmd_id */
+ __u32 id;
+ /* flags for sub-commend. If sub-command doesn't use this, set zero. */
+ __u32 flags;
+ /*
+ * data for each sub-command. An immediate or a pointer to the actual
+ * data in process virtual address. If sub-command doesn't use it,
+ * set zero.
+ */
+ __u64 data;
+ /*
+ * Auxiliary error code. The sub-command may return TDX SEAMCALL
+ * status code in addition to -Exxx.
+ * Defined for consistency with struct kvm_sev_cmd.
+ */
+ __u64 error;
+ /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
+ __u64 unused;
+};
+
+struct kvm_tdx_cpuid_config {
+ __u32 leaf;
+ __u32 sub_leaf;
+ __u32 eax;
+ __u32 ebx;
+ __u32 ecx;
+ __u32 edx;
+};
+
+struct kvm_tdx_capabilities {
+ __u64 attrs_fixed0;
+ __u64 attrs_fixed1;
+ __u64 xfam_fixed0;
+ __u64 xfam_fixed1;
+
+ __u32 nr_cpuid_configs;
+ __u32 padding;
+ struct kvm_tdx_cpuid_config cpuid_configs[0];
+};
+
#endif /* _ASM_X86_KVM_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX has its own limitation on the maximum number of vcpus that the guest
can accommodate. Allow x86 kvm backend to implement its own KVM_ENABLE_CAP
handler and implement TDX backend for KVM_CAP_MAX_VCPUS. user space VMM,
e.g. qemu, can specify its value instead of KVM_MAX_VCPUS.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 2 ++
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/vmx/main.c | 22 ++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.c | 30 ++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 3 +++
arch/x86/kvm/vmx/x86_ops.h | 2 ++
arch/x86/kvm/x86.c | 4 ++++
7 files changed, 65 insertions(+)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 58fbaa05fc8c..7522c193f2b4 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -21,6 +21,8 @@ KVM_X86_OP(hardware_unsetup)
KVM_X86_OP(has_emulated_msr)
KVM_X86_OP(vcpu_after_set_cpuid)
KVM_X86_OP(is_vm_type_supported)
+KVM_X86_OP_OPTIONAL(max_vcpus);
+KVM_X86_OP_OPTIONAL(vm_enable_cap)
KVM_X86_OP(vm_init)
KVM_X86_OP_OPTIONAL(vm_destroy)
KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 49e3ca89aced..d98d61e5213d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1562,7 +1562,9 @@ struct kvm_x86_ops {
void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
bool (*is_vm_type_supported)(unsigned long vm_type);
+ int (*max_vcpus)(struct kvm *kvm);
unsigned int vm_size;
+ int (*vm_enable_cap)(struct kvm *kvm, struct kvm_enable_cap *cap);
int (*vm_init)(struct kvm *kvm);
void (*vm_destroy)(struct kvm *kvm);
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 8ddd263eeabc..68bb320d0b6d 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -6,6 +6,7 @@
#include "nested.h"
#include "pmu.h"
#include "tdx.h"
+#include "tdx_arch.h"
static bool enable_tdx __ro_after_init;
module_param_named(tdx, enable_tdx, bool, 0444);
@@ -29,6 +30,17 @@ static bool vt_is_vm_type_supported(unsigned long type)
(enable_tdx && tdx_is_vm_type_supported(type));
}
+static int vt_max_vcpus(struct kvm *kvm)
+{
+ if (!kvm)
+ return KVM_MAX_VCPUS;
+
+ if (is_td(kvm))
+ return min3(kvm->max_vcpus, KVM_MAX_VCPUS, TDX_MAX_VCPUS);
+
+ return kvm->max_vcpus;
+}
+
static __init int vt_hardware_setup(void)
{
int ret;
@@ -42,6 +54,14 @@ static __init int vt_hardware_setup(void)
return 0;
}
+static int vt_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
+{
+ if (is_td(kvm))
+ return tdx_vm_enable_cap(kvm, cap);
+
+ return -EINVAL;
+}
+
static int vt_vm_init(struct kvm *kvm)
{
if (is_td(kvm))
@@ -81,7 +101,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.has_emulated_msr = vmx_has_emulated_msr,
.is_vm_type_supported = vt_is_vm_type_supported,
+ .max_vcpus = vt_max_vcpus,
.vm_size = sizeof(struct kvm_vmx),
+ .vm_enable_cap = vt_vm_enable_cap,
.vm_init = vt_vm_init,
.vm_destroy = vmx_vm_destroy,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index d759028a698e..8b02e605cfb5 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -16,6 +16,36 @@
offsetof(struct tdsysinfo_struct, cpuid_configs)) \
/ sizeof(struct tdx_cpuid_config))
+int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
+{
+ int r;
+
+ switch (cap->cap) {
+ case KVM_CAP_MAX_VCPUS: {
+ if (cap->flags || cap->args[0] == 0)
+ return -EINVAL;
+ if (cap->args[0] > KVM_MAX_VCPUS)
+ return -E2BIG;
+ if (cap->args[0] > TDX_MAX_VCPUS)
+ return -E2BIG;
+
+ mutex_lock(&kvm->lock);
+ if (kvm->created_vcpus)
+ r = -EBUSY;
+ else {
+ kvm->max_vcpus = cap->args[0];
+ r = 0;
+ }
+ mutex_unlock(&kvm->lock);
+ break;
+ }
+ default:
+ r = -EINVAL;
+ break;
+ }
+ return r;
+}
+
int tdx_hardware_enable(void)
{
return tdx_cpu_enable();
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 2210c8c1e893..3860aa351bd9 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -3,6 +3,9 @@
#define __KVM_X86_TDX_H
#ifdef CONFIG_INTEL_TDX_HOST
+
+#include "tdx_ops.h"
+
struct kvm_tdx {
struct kvm kvm;
/* TDX specific members follow. */
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index c70749114e9e..8118647aa8ca 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -143,6 +143,7 @@ int tdx_hardware_enable(void);
bool tdx_is_vm_type_supported(unsigned long type);
int tdx_dev_ioctl(void __user *argp);
+int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
@@ -150,6 +151,7 @@ static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
+static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
#endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8687623929c3..7b02dd40ef21 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4500,6 +4500,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
break;
case KVM_CAP_MAX_VCPUS:
r = KVM_MAX_VCPUS;
+ if (kvm_x86_ops.max_vcpus)
+ r = static_call(kvm_x86_max_vcpus)(kvm);
break;
case KVM_CAP_MAX_VCPU_ID:
r = KVM_MAX_VCPU_IDS;
@@ -6439,6 +6441,8 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
break;
default:
r = -EINVAL;
+ if (kvm_x86_ops.vm_enable_cap)
+ r = static_call(kvm_x86_vm_enable_cap)(kvm, cap);
break;
}
return r;
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of KVM TDP MMU
hooks.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index e893a3d714c7..7903473abad1 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -26,5 +26,5 @@ Patch Layer status
* TD vcpu interrupts/exit/hypercall: Not yet
* KVM MMU GPA shared bits: Applied
-* KVM TDP refactoring for TDX: Applying
-* KVM TDP MMU hooks: Not yet
+* KVM TDP refactoring for TDX: Applied
+* KVM TDP MMU hooks: Applying
--
2.25.1
From: Chao Gao <[email protected]>
Current TD guest doesn't invoke MAP_GPA to convert MMIO range to shared
before accessing it. It implies that current TD guest assumes MMIOs are
shared.
When TD tries to access assigned device's MMIO as shared, an EPT violation
is raised first. kvm_mem_is_private() checks the page shared or private
attribute against the access type (shared bit in GPA). Then since no
MAP_GPA is called for the MMIO, KVM thinks the MMIO is private and refuses
shared access and doesn't set up shared EPT. Then KVM returns to TD and TD
just retries and this causes an infinite loop.
Instead of requiring guest to invoke MAP_GPA for MMIOs, assume guest MMIOs
are shared in KVM as well and don't expect explicit calls of MAP_GAP for
guest MMIOs (i.e., GPAs either have no kvm_memory_slot or are backed by
host MMIOs). So, allow shared access to guest MMIOs and move the page type
check after the corresponding pfn is available.
Signed-off-by: Chao Gao <[email protected]>
---
arch/x86/kvm/mmu/mmu.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 5883ab95ff07..ce8a896a3cfa 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4314,7 +4314,12 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
return RET_PF_EMULATE;
}
- if (fault->is_private != kvm_mem_is_private(vcpu->kvm, fault->gfn))
+ /*
+ * !fault->slot means MMIO. Don't require explicit GPA conversion for
+ * MMIO because MMIO is assigned at the boot time.
+ */
+ if (fault->slot &&
+ fault->is_private != kvm_mem_is_private(vcpu->kvm, fault->gfn))
return kvm_do_memory_fault_exit(vcpu, fault);
if (fault->is_private)
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because TDX KVM doesn't support PMU yet (it's future work of TDX KVM
support as another patch series) and pmu_intel.c touches vmx specific
structure in vcpu initialization, as workaround add dummy structure to
struct vcpu_tdx and pmu_intel.c can ignore TDX case.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/pmu_intel.c | 46 +++++++++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/pmu_intel.h | 28 ++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 8 ++++++-
arch/x86/kvm/vmx/vmx.c | 2 +-
arch/x86/kvm/vmx/vmx.h | 32 +------------------------
5 files changed, 82 insertions(+), 34 deletions(-)
create mode 100644 arch/x86/kvm/vmx/pmu_intel.h
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index e8a3be0b9df9..df1f4ddfa72d 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -19,6 +19,7 @@
#include "lapic.h"
#include "nested.h"
#include "pmu.h"
+#include "tdx.h"
#define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
@@ -40,6 +41,26 @@ static struct {
/* mapping between fixed pmc index and intel_arch_events array */
static int fixed_pmc_events[] = {1, 0, 7};
+struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_INTEL_TDX_HOST
+ if (is_td_vcpu(vcpu))
+ return &to_tdx(vcpu)->lbr_desc;
+#endif
+
+ return &to_vmx(vcpu)->lbr_desc;
+}
+
+struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_INTEL_TDX_HOST
+ if (is_td_vcpu(vcpu))
+ return &to_tdx(vcpu)->lbr_desc.records;
+#endif
+
+ return &to_vmx(vcpu)->lbr_desc.records;
+}
+
static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
{
struct kvm_pmc *pmc;
@@ -172,6 +193,23 @@ static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
}
+bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return false;
+ return cpuid_model_is_consistent(vcpu);
+}
+
+bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
+{
+ struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
+
+ if (is_td_vcpu(vcpu))
+ return false;
+
+ return lbr->nr && (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_LBR_FMT);
+}
+
static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index)
{
struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu);
@@ -282,6 +320,9 @@ int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu)
PERF_SAMPLE_BRANCH_USER,
};
+ if (WARN_ON_ONCE(is_td_vcpu(vcpu)))
+ return 0;
+
if (unlikely(lbr_desc->event)) {
__set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
return 0;
@@ -591,7 +632,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
perf_capabilities = vcpu_get_perf_capabilities(vcpu);
- if (cpuid_model_is_consistent(vcpu) &&
+ if (intel_pmu_lbr_is_compatible(vcpu) &&
(perf_capabilities & PMU_CAP_LBR_FMT))
x86_perf_get_lbr(&lbr_desc->records);
else
@@ -647,6 +688,9 @@ static void intel_pmu_reset(struct kvm_vcpu *vcpu)
struct kvm_pmc *pmc = NULL;
int i;
+ if (is_td_vcpu(vcpu))
+ return;
+
for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) {
pmc = &pmu->gp_counters[i];
diff --git a/arch/x86/kvm/vmx/pmu_intel.h b/arch/x86/kvm/vmx/pmu_intel.h
new file mode 100644
index 000000000000..66bba47c1269
--- /dev/null
+++ b/arch/x86/kvm/vmx/pmu_intel.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __KVM_X86_VMX_PMU_INTEL_H
+#define __KVM_X86_VMX_PMU_INTEL_H
+
+struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu);
+struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu);
+
+bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu);
+bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu);
+int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu);
+
+struct lbr_desc {
+ /* Basic info about guest LBR records. */
+ struct x86_pmu_lbr records;
+
+ /*
+ * Emulate LBR feature via passthrough LBR registers when the
+ * per-vcpu guest LBR event is scheduled on the current pcpu.
+ *
+ * The records may be inaccurate if the host reclaims the LBR.
+ */
+ struct perf_event *event;
+
+ /* True if LBRs are marked as not intercepted in the MSR bitmap */
+ bool msr_passthrough;
+};
+
+#endif /* __KVM_X86_VMX_PMU_INTEL_H */
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 1e00e75b1c5e..5728820fed5e 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -4,6 +4,7 @@
#ifdef CONFIG_INTEL_TDX_HOST
+#include "pmu_intel.h"
#include "tdx_ops.h"
struct kvm_tdx {
@@ -21,7 +22,12 @@ struct kvm_tdx {
struct vcpu_tdx {
struct kvm_vcpu vcpu;
- /* TDX specific members follow. */
+
+ /*
+ * Dummy to make pmu_intel not corrupt memory.
+ * TODO: Support PMU for TDX. Future work.
+ */
+ struct lbr_desc lbr_desc;
};
static inline bool is_td(struct kvm *kvm)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index d23830d92f61..f9e9fd7fde2c 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2432,7 +2432,7 @@ int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if ((data & PMU_CAP_LBR_FMT) !=
(kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT))
return 1;
- if (!cpuid_model_is_consistent(vcpu))
+ if (!intel_pmu_lbr_is_compatible(vcpu))
return 1;
}
if (data & PERF_CAP_PEBS_FORMAT) {
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 2acdc54bc34b..1d15c3c2751b 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -11,6 +11,7 @@
#include "capabilities.h"
#include "../kvm_cache_regs.h"
#include "posted_intr.h"
+#include "pmu_intel.h"
#include "vmcs.h"
#include "vmx_ops.h"
#include "../cpuid.h"
@@ -105,22 +106,6 @@ static inline bool intel_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
return pmu->version > 1;
}
-struct lbr_desc {
- /* Basic info about guest LBR records. */
- struct x86_pmu_lbr records;
-
- /*
- * Emulate LBR feature via passthrough LBR registers when the
- * per-vcpu guest LBR event is scheduled on the current pcpu.
- *
- * The records may be inaccurate if the host reclaims the LBR.
- */
- struct perf_event *event;
-
- /* True if LBRs are marked as not intercepted in the MSR bitmap */
- bool msr_passthrough;
-};
-
/*
* The nested_vmx structure is part of vcpu_vmx, and holds information we need
* for correct emulation of VMX (i.e., nested VMX) on this vcpu.
@@ -650,21 +635,6 @@ static __always_inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
return container_of(vcpu, struct vcpu_vmx, vcpu);
}
-static inline struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu)
-{
- return &to_vmx(vcpu)->lbr_desc;
-}
-
-static inline struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
-{
- return &vcpu_to_lbr_desc(vcpu)->records;
-}
-
-static inline bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
-{
- return !!vcpu_to_lbr_records(vcpu)->nr;
-}
-
void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu);
int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu);
void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu);
--
2.25.1
From: Isaku Yamahata <[email protected]>
As the first step to create TDX guest, create/destroy VM struct. Assign
TDX private Host Key ID (HKID) to the TDX guest for memory encryption and
allocate extra pages for the TDX guest. On destruction, free allocated
pages, and HKID.
Before tearing down private page tables, TDX requires some resources of the
guest TD to be destroyed (i.e. HKID must have been reclaimed, etc). Add
flush_shadow_all_private callback before tearing down private page tables
for it.
Add vm_free() of kvm_x86_ops hook at the end of kvm_arch_destroy_vm()
because some per-VM TDX resources, e.g. TDR, need to be freed after other
TDX resources, e.g. HKID, were freed.
Co-developed-by: Kai Huang <[email protected]>
Signed-off-by: Kai Huang <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
Changes v11 -> v12:
- use cpu_feature_enabled().
Changes v10 -> v11:
- Fix doule free in tdx_vm_free() by setting NULL.
- replace struct tdx_td_page tdr and tdcs from struct kvm_tdx with
unsigned long
---
arch/x86/include/asm/kvm-x86-ops.h | 2 +
arch/x86/include/asm/kvm_host.h | 2 +
arch/x86/kvm/vmx/main.c | 35 ++-
arch/x86/kvm/vmx/tdx.c | 442 ++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 6 +-
arch/x86/kvm/vmx/x86_ops.h | 9 +
arch/x86/kvm/x86.c | 8 +
7 files changed, 498 insertions(+), 6 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 7522c193f2b4..c30d2d2ad686 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -24,7 +24,9 @@ KVM_X86_OP(is_vm_type_supported)
KVM_X86_OP_OPTIONAL(max_vcpus);
KVM_X86_OP_OPTIONAL(vm_enable_cap)
KVM_X86_OP(vm_init)
+KVM_X86_OP_OPTIONAL(flush_shadow_all_private)
KVM_X86_OP_OPTIONAL(vm_destroy)
+KVM_X86_OP_OPTIONAL(vm_free)
KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
KVM_X86_OP(vcpu_create)
KVM_X86_OP(vcpu_free)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d98d61e5213d..15f7c0d45082 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1566,7 +1566,9 @@ struct kvm_x86_ops {
unsigned int vm_size;
int (*vm_enable_cap)(struct kvm *kvm, struct kvm_enable_cap *cap);
int (*vm_init)(struct kvm *kvm);
+ void (*flush_shadow_all_private)(struct kvm *kvm);
void (*vm_destroy)(struct kvm *kvm);
+ void (*vm_free)(struct kvm *kvm);
/* Create, but do not attach this VCPU */
int (*vcpu_precreate)(struct kvm *kvm);
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 68bb320d0b6d..08ed6fc8cc3d 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -62,14 +62,41 @@ static int vt_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
return -EINVAL;
}
+static void vt_hardware_unsetup(void)
+{
+ if (enable_tdx)
+ tdx_hardware_unsetup();
+ vmx_hardware_unsetup();
+}
+
static int vt_vm_init(struct kvm *kvm)
{
if (is_td(kvm))
- return -EOPNOTSUPP; /* Not ready to create guest TD yet. */
+ return tdx_vm_init(kvm);
return vmx_vm_init(kvm);
}
+static void vt_flush_shadow_all_private(struct kvm *kvm)
+{
+ if (is_td(kvm))
+ tdx_mmu_release_hkid(kvm);
+}
+
+static void vt_vm_destroy(struct kvm *kvm)
+{
+ if (is_td(kvm))
+ return;
+
+ vmx_vm_destroy(kvm);
+}
+
+static void vt_vm_free(struct kvm *kvm)
+{
+ if (is_td(kvm))
+ tdx_vm_free(kvm);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -94,7 +121,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.check_processor_compatibility = vmx_check_processor_compat,
- .hardware_unsetup = vmx_hardware_unsetup,
+ .hardware_unsetup = vt_hardware_unsetup,
.hardware_enable = vt_hardware_enable,
.hardware_disable = vmx_hardware_disable,
@@ -105,7 +132,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vm_size = sizeof(struct kvm_vmx),
.vm_enable_cap = vt_vm_enable_cap,
.vm_init = vt_vm_init,
- .vm_destroy = vmx_vm_destroy,
+ .flush_shadow_all_private = vt_flush_shadow_all_private,
+ .vm_destroy = vt_vm_destroy,
+ .vm_free = vt_vm_free,
.vcpu_precreate = vmx_vcpu_precreate,
.vcpu_create = vmx_vcpu_create,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 8b02e605cfb5..3ede8a726b47 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -5,8 +5,9 @@
#include "capabilities.h"
#include "x86_ops.h"
-#include "x86.h"
#include "tdx.h"
+#include "tdx_ops.h"
+#include "x86.h"
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -46,11 +47,276 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
return r;
}
+struct tdx_info {
+ u8 nr_tdcs_pages;
+};
+
+/* Info about the TDX module. */
+static struct tdx_info tdx_info;
+
+/*
+ * Some TDX SEAMCALLs (TDH.MNG.CREATE, TDH.PHYMEM.CACHE.WB,
+ * TDH.MNG.KEY.RECLAIMID, TDH.MNG.KEY.FREEID etc) tries to acquire a global lock
+ * internally in TDX module. If failed, TDX_OPERAND_BUSY is returned without
+ * spinning or waiting due to a constraint on execution time. It's caller's
+ * responsibility to avoid race (or retry on TDX_OPERAND_BUSY). Use this mutex
+ * to avoid race in TDX module because the kernel knows better about scheduling.
+ */
+static DEFINE_MUTEX(tdx_lock);
+static struct mutex *tdx_mng_key_config_lock;
+
+static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
+{
+ return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
+}
+
+static inline bool is_td_created(struct kvm_tdx *kvm_tdx)
+{
+ return kvm_tdx->tdr_pa;
+}
+
+static inline void tdx_hkid_free(struct kvm_tdx *kvm_tdx)
+{
+ tdx_guest_keyid_free(kvm_tdx->hkid);
+ kvm_tdx->hkid = 0;
+}
+
+static inline bool is_hkid_assigned(struct kvm_tdx *kvm_tdx)
+{
+ return kvm_tdx->hkid > 0;
+}
+
int tdx_hardware_enable(void)
{
return tdx_cpu_enable();
}
+static void tdx_clear_page(unsigned long page_pa)
+{
+ const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
+ void *page = __va(page_pa);
+ unsigned long i;
+
+ if (!cpu_feature_enabled(X86_FEATURE_MOVDIR64B)) {
+ clear_page(page);
+ return;
+ }
+
+ /*
+ * Zeroing the page is only necessary for systems with MKTME-i:
+ * when re-assign one page from old keyid to a new keyid, MOVDIR64B is
+ * required to clear/write the page with new keyid to prevent integrity
+ * error when read on the page with new keyid.
+ *
+ * clflush doesn't flush cache with HKID set.
+ * The cache line could be poisoned (even without MKTME-i), clear the
+ * poison bit.
+ */
+ for (i = 0; i < PAGE_SIZE; i += 64)
+ movdir64b(page + i, zero_page);
+ /*
+ * MOVDIR64B store uses WC buffer. Prevent following memory reads
+ * from seeing potentially poisoned cache.
+ */
+ __mb();
+}
+
+static int tdx_reclaim_page(hpa_t pa, bool do_wb, u16 hkid)
+{
+ struct tdx_module_output out;
+ u64 err;
+
+ do {
+ err = tdh_phymem_page_reclaim(pa, &out);
+ /*
+ * TDH.PHYMEM.PAGE.RECLAIM is allowed only when TD is shutdown.
+ * state. i.e. destructing TD.
+ * TDH.PHYMEM.PAGE.RECLAIM requires TDR and target page.
+ * Because we're destructing TD, it's rare to contend with TDR.
+ */
+ } while (err == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_RCX));
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_PHYMEM_PAGE_RECLAIM, err, &out);
+ return -EIO;
+ }
+
+ if (do_wb) {
+ /*
+ * Only TDR page gets into this path. No contention is expected
+ * because of the last page of TD.
+ */
+ err = tdh_phymem_page_wbinvd(set_hkid_to_hpa(pa, hkid));
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_PHYMEM_PAGE_WBINVD, err, NULL);
+ return -EIO;
+ }
+ }
+
+ tdx_clear_page(pa);
+ return 0;
+}
+
+static void tdx_reclaim_td_page(unsigned long td_page_pa)
+{
+ if (!td_page_pa)
+ return;
+ /*
+ * TDCX are being reclaimed. TDX module maps TDCX with HKID
+ * assigned to the TD. Here the cache associated to the TD
+ * was already flushed by TDH.PHYMEM.CACHE.WB before here, So
+ * cache doesn't need to be flushed again.
+ */
+ if (tdx_reclaim_page(td_page_pa, false, 0))
+ /*
+ * Leak the page on failure:
+ * tdx_reclaim_page() returns an error if and only if there's an
+ * unexpected, fatal error, e.g. a SEAMCALL with bad params,
+ * incorrect concurrency in KVM, a TDX Module bug, etc.
+ * Retrying at a later point is highly unlikely to be
+ * successful.
+ * No log here as tdx_reclaim_page() already did.
+ */
+ return;
+ free_page((unsigned long)__va(td_page_pa));
+}
+
+static int tdx_do_tdh_phymem_cache_wb(void *param)
+{
+ u64 err = 0;
+
+ do {
+ err = tdh_phymem_cache_wb(!!err);
+ } while (err == TDX_INTERRUPTED_RESUMABLE);
+
+ /* Other thread may have done for us. */
+ if (err == TDX_NO_HKID_READY_TO_WBCACHE)
+ err = TDX_SUCCESS;
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_PHYMEM_CACHE_WB, err, NULL);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+void tdx_mmu_release_hkid(struct kvm *kvm)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ cpumask_var_t packages;
+ bool cpumask_allocated;
+ u64 err;
+ int ret;
+ int i;
+
+ if (!is_hkid_assigned(kvm_tdx))
+ return;
+
+ if (!is_td_created(kvm_tdx))
+ goto free_hkid;
+
+ cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
+ cpus_read_lock();
+ for_each_online_cpu(i) {
+ if (cpumask_allocated &&
+ cpumask_test_and_set_cpu(topology_physical_package_id(i),
+ packages))
+ continue;
+
+ /*
+ * We can destroy multiple the guest TDs simultaneously.
+ * Prevent tdh_phymem_cache_wb from returning TDX_BUSY by
+ * serialization.
+ */
+ mutex_lock(&tdx_lock);
+ ret = smp_call_on_cpu(i, tdx_do_tdh_phymem_cache_wb, NULL, 1);
+ mutex_unlock(&tdx_lock);
+ if (ret)
+ break;
+ }
+ cpus_read_unlock();
+ free_cpumask_var(packages);
+
+ mutex_lock(&tdx_lock);
+ err = tdh_mng_key_freeid(kvm_tdx->tdr_pa);
+ mutex_unlock(&tdx_lock);
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MNG_KEY_FREEID, err, NULL);
+ pr_err("tdh_mng_key_freeid failed. HKID %d is leaked.\n",
+ kvm_tdx->hkid);
+ return;
+ }
+
+free_hkid:
+ tdx_hkid_free(kvm_tdx);
+}
+
+void tdx_vm_free(struct kvm *kvm)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ int i;
+
+ /* Can't reclaim or free TD pages if teardown failed. */
+ if (is_hkid_assigned(kvm_tdx))
+ return;
+
+ if (kvm_tdx->tdcs_pa) {
+ for (i = 0; i < tdx_info.nr_tdcs_pages; i++)
+ tdx_reclaim_td_page(kvm_tdx->tdcs_pa[i]);
+ kfree(kvm_tdx->tdcs_pa);
+ kvm_tdx->tdcs_pa = NULL;
+ }
+
+ if (!kvm_tdx->tdr_pa)
+ return;
+ /*
+ * TDX module maps TDR with TDX global HKID. TDX module may access TDR
+ * while operating on TD (Especially reclaiming TDCS). Cache flush with
+ * TDX global HKID is needed.
+ */
+ if (tdx_reclaim_page(kvm_tdx->tdr_pa, true, tdx_global_keyid))
+ return;
+
+ free_page((unsigned long)__va(kvm_tdx->tdr_pa));
+ kvm_tdx->tdr_pa = 0;
+}
+
+static int tdx_do_tdh_mng_key_config(void *param)
+{
+ hpa_t *tdr_p = param;
+ u64 err;
+
+ do {
+ err = tdh_mng_key_config(*tdr_p);
+
+ /*
+ * If it failed to generate a random key, retry it because this
+ * is typically caused by an entropy error of the CPU's random
+ * number generator.
+ */
+ } while (err == TDX_KEY_GENERATION_FAILED);
+
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MNG_KEY_CONFIG, err, NULL);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int __tdx_td_init(struct kvm *kvm);
+
+int tdx_vm_init(struct kvm *kvm)
+{
+ /*
+ * TDX has its own limit of the number of vcpus in addition to
+ * KVM_MAX_VCPUS.
+ */
+ kvm->max_vcpus = min(kvm->max_vcpus, TDX_MAX_VCPUS);
+
+ /* Place holder for TDX specific logic. */
+ return __tdx_td_init(kvm);
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
@@ -102,6 +368,160 @@ int tdx_dev_ioctl(void __user *argp)
return 0;
}
+static int __tdx_td_init(struct kvm *kvm)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ cpumask_var_t packages;
+ unsigned long *tdcs_pa = NULL;
+ unsigned long tdr_pa = 0;
+ unsigned long va;
+ int ret, i;
+ u64 err;
+
+ ret = tdx_guest_keyid_alloc();
+ if (ret < 0)
+ return ret;
+ kvm_tdx->hkid = ret;
+
+ va = __get_free_page(GFP_KERNEL_ACCOUNT);
+ if (!va)
+ goto free_hkid;
+ tdr_pa = __pa(va);
+
+ tdcs_pa = kcalloc(tdx_info.nr_tdcs_pages, sizeof(*kvm_tdx->tdcs_pa),
+ GFP_KERNEL_ACCOUNT | __GFP_ZERO);
+ if (!tdcs_pa)
+ goto free_tdr;
+ for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
+ va = __get_free_page(GFP_KERNEL_ACCOUNT);
+ if (!va)
+ goto free_tdcs;
+ tdcs_pa[i] = __pa(va);
+ }
+
+ if (!zalloc_cpumask_var(&packages, GFP_KERNEL)) {
+ ret = -ENOMEM;
+ goto free_tdcs;
+ }
+ cpus_read_lock();
+ /*
+ * Need at least one CPU of the package to be online in order to
+ * program all packages for host key id. Check it.
+ */
+ for_each_present_cpu(i)
+ cpumask_set_cpu(topology_physical_package_id(i), packages);
+ for_each_online_cpu(i)
+ cpumask_clear_cpu(topology_physical_package_id(i), packages);
+ if (!cpumask_empty(packages)) {
+ ret = -EIO;
+ /*
+ * Because it's hard for human operator to figure out the
+ * reason, warn it.
+ */
+ pr_warn("All packages need to have online CPU to create TD. Online CPU and retry.\n");
+ goto free_packages;
+ }
+
+ /*
+ * Acquire global lock to avoid TDX_OPERAND_BUSY:
+ * TDH.MNG.CREATE and other APIs try to lock the global Key Owner
+ * Table (KOT) to track the assigned TDX private HKID. It doesn't spin
+ * to acquire the lock, returns TDX_OPERAND_BUSY instead, and let the
+ * caller to handle the contention. This is because of time limitation
+ * usable inside the TDX module and OS/VMM knows better about process
+ * scheduling.
+ *
+ * APIs to acquire the lock of KOT:
+ * TDH.MNG.CREATE, TDH.MNG.KEY.FREEID, TDH.MNG.VPFLUSHDONE, and
+ * TDH.PHYMEM.CACHE.WB.
+ */
+ mutex_lock(&tdx_lock);
+ err = tdh_mng_create(tdr_pa, kvm_tdx->hkid);
+ mutex_unlock(&tdx_lock);
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MNG_CREATE, err, NULL);
+ ret = -EIO;
+ goto free_packages;
+ }
+ kvm_tdx->tdr_pa = tdr_pa;
+
+ for_each_online_cpu(i) {
+ int pkg = topology_physical_package_id(i);
+
+ if (cpumask_test_and_set_cpu(pkg, packages))
+ continue;
+
+ /*
+ * Program the memory controller in the package with an
+ * encryption key associated to a TDX private host key id
+ * assigned to this TDR. Concurrent operations on same memory
+ * controller results in TDX_OPERAND_BUSY. Avoid this race by
+ * mutex.
+ */
+ mutex_lock(&tdx_mng_key_config_lock[pkg]);
+ ret = smp_call_on_cpu(i, tdx_do_tdh_mng_key_config,
+ &kvm_tdx->tdr_pa, true);
+ mutex_unlock(&tdx_mng_key_config_lock[pkg]);
+ if (ret)
+ break;
+ }
+ cpus_read_unlock();
+ free_cpumask_var(packages);
+ if (ret)
+ goto teardown;
+
+ kvm_tdx->tdcs_pa = tdcs_pa;
+ for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
+ err = tdh_mng_addcx(kvm_tdx->tdr_pa, tdcs_pa[i]);
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MNG_ADDCX, err, NULL);
+ for (i++; i < tdx_info.nr_tdcs_pages; i++) {
+ free_page((unsigned long)__va(tdcs_pa[i]));
+ tdcs_pa[i] = 0;
+ }
+ ret = -EIO;
+ goto teardown;
+ }
+ }
+
+ /*
+ * Note, TDH_MNG_INIT cannot be invoked here. TDH_MNG_INIT requires a dedicated
+ * ioctl() to define the configure CPUID values for the TD.
+ */
+ return 0;
+
+ /*
+ * The sequence for freeing resources from a partially initialized TD
+ * varies based on where in the initialization flow failure occurred.
+ * Simply use the full teardown and destroy, which naturally play nice
+ * with partial initialization.
+ */
+teardown:
+ tdx_mmu_release_hkid(kvm);
+ tdx_vm_free(kvm);
+ return ret;
+
+free_packages:
+ cpus_read_unlock();
+ free_cpumask_var(packages);
+free_tdcs:
+ for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
+ if (tdcs_pa[i])
+ free_page((unsigned long)__va(tdcs_pa[i]));
+ }
+ kfree(tdcs_pa);
+ kvm_tdx->tdcs_pa = NULL;
+
+free_tdr:
+ if (tdr_pa)
+ free_page((unsigned long)__va(tdr_pa));
+ kvm_tdx->tdr_pa = 0;
+free_hkid:
+ if (is_hkid_assigned(kvm_tdx))
+ tdx_hkid_free(kvm_tdx);
+ return ret;
+}
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_tdx_cmd tdx_cmd;
@@ -142,9 +562,11 @@ static int __init tdx_module_setup(void)
return ret;
}
- /* Sanitary check just in case. */
tdsysinfo = tdx_get_sysinfo();
WARN_ON(tdsysinfo->num_cpuid_config > TDX_MAX_NR_CPUID_CONFIGS);
+ tdx_info = (struct tdx_info) {
+ .nr_tdcs_pages = tdsysinfo->tdcs_base_size / PAGE_SIZE,
+ };
pr_info("TDX is supported.\n");
return 0;
@@ -163,6 +585,8 @@ static int __init tdx_cpu_enable_cpu(void *unused)
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
{
+ int max_pkgs;
+ int i;
int r;
if (!enable_ept) {
@@ -170,6 +594,14 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
return -EINVAL;
}
+ max_pkgs = topology_max_packages();
+ tdx_mng_key_config_lock = kcalloc(max_pkgs, sizeof(*tdx_mng_key_config_lock),
+ GFP_KERNEL);
+ if (!tdx_mng_key_config_lock)
+ return -ENOMEM;
+ for (i = 0; i < max_pkgs; i++)
+ mutex_init(&tdx_mng_key_config_lock[i]);
+
/* tdx_enable() in tdx_module_setup() requires cpus lock. */
cpus_read_lock();
/* TDX requires VMX. */
@@ -193,3 +625,9 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
return r;
}
+
+void tdx_hardware_unsetup(void)
+{
+ /* kfree accepts NULL. */
+ kfree(tdx_mng_key_config_lock);
+}
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 3860aa351bd9..4b790503e43e 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -8,7 +8,11 @@
struct kvm_tdx {
struct kvm kvm;
- /* TDX specific members follow. */
+
+ unsigned long tdr_pa;
+ unsigned long *tdcs_pa;
+
+ int hkid;
};
struct vcpu_tdx {
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 8118647aa8ca..8f87eeeab97c 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -139,19 +139,28 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
#ifdef CONFIG_INTEL_TDX_HOST
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
+void tdx_hardware_unsetup(void);
int tdx_hardware_enable(void);
bool tdx_is_vm_type_supported(unsigned long type);
int tdx_dev_ioctl(void __user *argp);
int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
+int tdx_vm_init(struct kvm *kvm);
+void tdx_mmu_release_hkid(struct kvm *kvm);
+void tdx_vm_free(struct kvm *kvm);
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
+static inline void tdx_hardware_unsetup(void) {}
static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
+static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
+static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
+static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
+static inline void tdx_vm_free(struct kvm *kvm) {}
static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
#endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7b02dd40ef21..89fd8074c20c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12398,6 +12398,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
kvm_page_track_cleanup(kvm);
kvm_xen_destroy_vm(kvm);
kvm_hv_destroy_vm(kvm);
+ static_call_cond(kvm_x86_vm_free)(kvm);
}
static void memslot_rmap_free(struct kvm_memory_slot *slot)
@@ -12710,6 +12711,13 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
void kvm_arch_flush_shadow_all(struct kvm *kvm)
{
+ /*
+ * kvm_mmu_zap_all() zaps both private and shared page tables. Before
+ * tearing down private page tables, TDX requires some TD resources to
+ * be destroyed (i.e. keyID must have been reclaimed, etc). Invoke
+ * kvm_x86_flush_shadow_all_private() for this.
+ */
+ static_call_cond(kvm_x86_flush_shadow_all_private)(kvm);
kvm_mmu_zap_all(kvm);
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX requires additional parameters for TDX VM for confidential execution to
protect its confidentiality of its memory contents and its CPU state from
any other software, including VMM. When creating guest TD VM before
creating vcpu, the number of vcpu, TSC frequency (that is same among
vcpus. and it can't be changed.) CPUIDs which is emulated by the TDX
module. It means guest can trust those CPUIDs. and sha384 values for
measurement.
Add new subcommand, KVM_TDX_INIT_VM, to pass parameters for TDX guest. It
assigns encryption key to the TDX guest for memory encryption. TDX
encrypts memory per-guest bases. It assigns device model passes per-VM
parameters for the TDX guest. The maximum number of vcpus, tsc frequency
(TDX guest has fised VM-wide TSC frequency. not per-vcpu. The TDX guest
can not change it.), attributes (production or debug), available extended
features (which is reflected into guest XCR0, IA32_XSS MSR), cpuids, sha384
measurements, and etc.
This subcommand is called before creating vcpu and KVM_SET_CPUID2, i.e.
cpuids configurations aren't available yet. So CPUIDs configuration values
needs to be passed in struct kvm_tdx_init_vm. It's device model
responsibility to make this cpuid config for KVM_TDX_INIT_VM and
KVM_SET_CPUID2.
Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
Changes from v11 to v12
- ABI change. Changes struct kvm_tdx_init_vm layout
---
arch/x86/include/asm/tdx.h | 3 +
arch/x86/include/uapi/asm/kvm.h | 24 +++
arch/x86/kvm/cpuid.c | 7 +
arch/x86/kvm/cpuid.h | 2 +
arch/x86/kvm/vmx/tdx.c | 247 ++++++++++++++++++++++++--
arch/x86/kvm/vmx/tdx.h | 18 ++
tools/arch/x86/include/uapi/asm/kvm.h | 33 ++++
7 files changed, 324 insertions(+), 10 deletions(-)
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 05870e5ed131..bd09b03d7edd 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -101,6 +101,9 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
#endif /* CONFIG_INTEL_TDX_GUEST && CONFIG_KVM_GUEST */
#ifdef CONFIG_INTEL_TDX_HOST
+
+/* -1 indicates CPUID leaf with no sub-leaves. */
+#define TDX_CPUID_NO_SUBLEAF ((u32)-1)
struct tdx_cpuid_config {
u32 leaf;
u32 sub_leaf;
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index af4c5bd0af1c..68e8d544afe5 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -565,6 +565,7 @@ struct kvm_pmu_event_filter {
/* Trust Domain eXtension sub-ioctl() commands. */
enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
+ KVM_TDX_INIT_VM,
KVM_TDX_CMD_NR_MAX,
};
@@ -610,4 +611,27 @@ struct kvm_tdx_capabilities {
struct kvm_tdx_cpuid_config cpuid_configs[0];
};
+struct kvm_tdx_init_vm {
+ __u64 attributes;
+ __u64 mrconfigid[6]; /* sha384 digest */
+ __u64 mrowner[6]; /* sha384 digest */
+ __u64 mrownerconfig[6]; /* sha348 digest */
+ /*
+ * For future extensibility to make sizeof(struct kvm_tdx_init_vm) = 8KB.
+ * This should be enough given sizeof(TD_PARAMS) = 1024.
+ * 8KB was chosen given because
+ * sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES(=256) = 8KB.
+ */
+ __u64 reserved[1004];
+
+ /*
+ * KVM_TDX_INIT_VM is called before vcpu creation, thus before
+ * KVM_SET_CPUID2.
+ * This configuration supersedes KVM_SET_CPUID2s for VCPUs. The user
+ * space VMM, e.g. qemu, should make KVM_SET_CPUID2 consistent with this
+ * values.
+ */
+ struct kvm_cpuid2 cpuid;
+};
+
#endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 599aebec2d52..9cda9a3a558a 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -1386,6 +1386,13 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
return r;
}
+struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2( struct kvm_cpuid2 *cpuid,
+ u32 function, u32 index)
+{
+ return cpuid_entry2_find(cpuid->entries, cpuid->nent, function, index);
+}
+EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry2);
+
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
u32 function, u32 index)
{
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index b1658c0de847..a0e799297629 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -13,6 +13,8 @@ void kvm_set_cpu_caps(void);
void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
void kvm_update_pv_runtime(struct kvm_vcpu *vcpu);
+struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2(struct kvm_cpuid2 *cpuid,
+ u32 function, u32 index);
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
u32 function, u32 index);
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 3ede8a726b47..496410ec6334 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -6,7 +6,6 @@
#include "capabilities.h"
#include "x86_ops.h"
#include "tdx.h"
-#include "tdx_ops.h"
#include "x86.h"
#undef pr_fmt
@@ -303,18 +302,21 @@ static int tdx_do_tdh_mng_key_config(void *param)
return 0;
}
-static int __tdx_td_init(struct kvm *kvm);
-
int tdx_vm_init(struct kvm *kvm)
{
+ /*
+ * This function initializes only KVM software construct. It doesn't
+ * initialize TDX stuff, e.g. TDCS, TDR, TDCX, HKID etc.
+ * It is handled by KVM_TDX_INIT_VM, __tdx_td_init().
+ */
+
/*
* TDX has its own limit of the number of vcpus in addition to
* KVM_MAX_VCPUS.
*/
kvm->max_vcpus = min(kvm->max_vcpus, TDX_MAX_VCPUS);
- /* Place holder for TDX specific logic. */
- return __tdx_td_init(kvm);
+ return 0;
}
int tdx_dev_ioctl(void __user *argp)
@@ -368,9 +370,162 @@ int tdx_dev_ioctl(void __user *argp)
return 0;
}
-static int __tdx_td_init(struct kvm *kvm)
+static void setup_tdparams_eptp_controls(struct kvm_cpuid2 *cpuid, struct td_params *td_params)
+{
+ const struct kvm_cpuid_entry2 *entry;
+ int max_pa = 36;
+
+ entry = kvm_find_cpuid_entry2(cpuid, 0x80000008, 0);
+ if (entry)
+ max_pa = entry->eax & 0xff;
+
+ td_params->eptp_controls = VMX_EPTP_MT_WB;
+ /*
+ * No CPU supports 4-level && max_pa > 48.
+ * "5-level paging and 5-level EPT" section 4.1 4-level EPT
+ * "4-level EPT is limited to translating 48-bit guest-physical
+ * addresses."
+ * cpu_has_vmx_ept_5levels() check is just in case.
+ */
+ if (cpu_has_vmx_ept_5levels() && max_pa > 48) {
+ td_params->eptp_controls |= VMX_EPTP_PWL_5;
+ td_params->exec_controls |= TDX_EXEC_CONTROL_MAX_GPAW;
+ } else {
+ td_params->eptp_controls |= VMX_EPTP_PWL_4;
+ }
+}
+
+static void setup_tdparams_cpuids(const struct tdsysinfo_struct *tdsysinfo,
+ struct kvm_cpuid2 *cpuid,
+ struct td_params *td_params)
+{
+ int i;
+
+ /*
+ * td_params.cpuid_values: The number and the order of cpuid_value must
+ * be same to the one of struct tdsysinfo.{num_cpuid_config, cpuid_configs}
+ * It's assumed that td_params was zeroed.
+ */
+ for (i = 0; i < tdsysinfo->num_cpuid_config; i++) {
+ const struct tdx_cpuid_config *config = &tdsysinfo->cpuid_configs[i];
+ /* TDX_CPUID_NO_SUBLEAF in TDX CPUID_CONFIG means index = 0. */
+ u32 index = config->sub_leaf == TDX_CPUID_NO_SUBLEAF ? 0: config->sub_leaf;
+ const struct kvm_cpuid_entry2 *entry =
+ kvm_find_cpuid_entry2(cpuid, config->leaf, index);
+ struct tdx_cpuid_value *value = &td_params->cpuid_values[i];
+
+ if (!entry)
+ continue;
+
+ /*
+ * tdsysinfo.cpuid_configs[].{eax, ebx, ecx, edx}
+ * bit 1 means it can be configured to zero or one.
+ * bit 0 means it must be zero.
+ * Mask out non-configurable bits.
+ */
+ value->eax = entry->eax & config->eax;
+ value->ebx = entry->ebx & config->ebx;
+ value->ecx = entry->ecx & config->ecx;
+ value->edx = entry->edx & config->edx;
+ }
+}
+
+static int setup_tdparams_xfam(struct kvm_cpuid2 *cpuid, struct td_params *td_params)
+{
+ const struct kvm_cpuid_entry2 *entry;
+ u64 guest_supported_xcr0;
+ u64 guest_supported_xss;
+
+ /* Setup td_params.xfam */
+ entry = kvm_find_cpuid_entry2(cpuid, 0xd, 0);
+ if (entry)
+ guest_supported_xcr0 = (entry->eax | ((u64)entry->edx << 32));
+ else
+ guest_supported_xcr0 = 0;
+ guest_supported_xcr0 &= kvm_caps.supported_xcr0;
+
+ entry = kvm_find_cpuid_entry2(cpuid, 0xd, 1);
+ if (entry)
+ guest_supported_xss = (entry->ecx | ((u64)entry->edx << 32));
+ else
+ guest_supported_xss = 0;
+ /* PT can be exposed to TD guest regardless of KVM's XSS support */
+ guest_supported_xss &= (kvm_caps.supported_xss | XFEATURE_MASK_PT);
+
+ td_params->xfam = guest_supported_xcr0 | guest_supported_xss;
+ if (td_params->xfam & XFEATURE_MASK_LBR) {
+ /*
+ * TODO: once KVM supports LBR(save/restore LBR related
+ * registers around TDENTER), remove this guard.
+ */
+ pr_warn("TD doesn't support LBR yet. KVM needs to save/restore "
+ "IA32_LBR_DEPTH properly.\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (td_params->xfam & XFEATURE_MASK_XTILE) {
+ /*
+ * TODO: once KVM supports AMX(save/restore AMX related
+ * registers around TDENTER), remove this guard.
+ */
+ pr_warn("TD doesn't support AMX yet. KVM needs to save/restore "
+ "IA32_XFD, IA32_XFD_ERR properly.\n");
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int setup_tdparams(struct kvm *kvm, struct td_params *td_params,
+ struct kvm_tdx_init_vm *init_vm)
+{
+ struct kvm_cpuid2 *cpuid = &init_vm->cpuid;
+ const struct tdsysinfo_struct *tdsysinfo;
+ int ret;
+
+ tdsysinfo = tdx_get_sysinfo();
+ if (!tdsysinfo)
+ return -ENOTSUPP;
+ if (kvm->created_vcpus)
+ return -EBUSY;
+
+ if (td_params->attributes & TDX_TD_ATTRIBUTE_PERFMON) {
+ /*
+ * TODO: save/restore PMU related registers around TDENTER.
+ * Once it's done, remove this guard.
+ */
+ pr_warn("TD doesn't support perfmon yet. KVM needs to save/restore "
+ "host perf registers properly.\n");
+ return -EOPNOTSUPP;
+ }
+
+ td_params->max_vcpus = kvm->max_vcpus;
+ td_params->attributes = init_vm->attributes;
+ td_params->tsc_frequency = TDX_TSC_KHZ_TO_25MHZ(kvm->arch.default_tsc_khz);
+
+ setup_tdparams_eptp_controls(cpuid, td_params);
+ setup_tdparams_cpuids(tdsysinfo, cpuid, td_params);
+ ret = setup_tdparams_xfam(cpuid, td_params);
+ if (ret)
+ return ret;
+
+#define MEMCPY_SAME_SIZE(dst, src) \
+ do { \
+ BUILD_BUG_ON(sizeof(dst) != sizeof(src)); \
+ memcpy((dst), (src), sizeof(dst)); \
+ } while (0)
+
+ MEMCPY_SAME_SIZE(td_params->mrconfigid, init_vm->mrconfigid);
+ MEMCPY_SAME_SIZE(td_params->mrowner, init_vm->mrowner);
+ MEMCPY_SAME_SIZE(td_params->mrownerconfig, init_vm->mrownerconfig);
+
+ return 0;
+}
+
+static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params)
{
struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ struct tdx_module_output out;
cpumask_var_t packages;
unsigned long *tdcs_pa = NULL;
unsigned long tdr_pa = 0;
@@ -484,10 +639,13 @@ static int __tdx_td_init(struct kvm *kvm)
}
}
- /*
- * Note, TDH_MNG_INIT cannot be invoked here. TDH_MNG_INIT requires a dedicated
- * ioctl() to define the configure CPUID values for the TD.
- */
+ err = tdh_mng_init(kvm_tdx->tdr_pa, __pa(td_params), &out);
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MNG_INIT, err, &out);
+ ret = -EIO;
+ goto teardown;
+ }
+
return 0;
/*
@@ -522,6 +680,72 @@ static int __tdx_td_init(struct kvm *kvm)
return ret;
}
+static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ struct kvm_tdx_init_vm *init_vm = NULL;
+ struct td_params *td_params = NULL;
+ int ret;
+
+ BUILD_BUG_ON(sizeof(*init_vm) != 8 * 1024);
+ BUILD_BUG_ON(sizeof(struct td_params) != 1024);
+
+ if (is_hkid_assigned(kvm_tdx))
+ return -EINVAL;
+
+ if (cmd->flags)
+ return -EINVAL;
+
+ init_vm = kzalloc(sizeof(*init_vm) +
+ sizeof(init_vm->cpuid.entries[0]) * KVM_MAX_CPUID_ENTRIES,
+ GFP_KERNEL);
+ if (!init_vm)
+ return -ENOMEM;
+ if (copy_from_user(init_vm, (void __user *)cmd->data, sizeof(*init_vm))) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (init_vm->cpuid.nent > KVM_MAX_CPUID_ENTRIES) {
+ ret = -E2BIG;
+ goto out;
+ }
+ if (copy_from_user(init_vm->cpuid.entries,
+ (void __user *)cmd->data + sizeof(*init_vm),
+ sizeof(init_vm->cpuid.entries[0]) * init_vm->cpuid.nent)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ if (init_vm->cpuid.padding) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ td_params = kzalloc(sizeof(struct td_params), GFP_KERNEL);
+ if (!td_params) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = setup_tdparams(kvm, td_params, init_vm);
+ if (ret)
+ goto out;
+
+ ret = __tdx_td_init(kvm, td_params);
+ if (ret)
+ goto out;
+
+ kvm_tdx->tsc_offset = td_tdcs_exec_read64(kvm_tdx, TD_TDCS_EXEC_TSC_OFFSET);
+ kvm_tdx->attributes = td_params->attributes;
+ kvm_tdx->xfam = td_params->xfam;
+
+out:
+ /* kfree() accepts NULL. */
+ kfree(init_vm);
+ kfree(td_params);
+ return ret;
+}
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_tdx_cmd tdx_cmd;
@@ -535,6 +759,9 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
mutex_lock(&kvm->lock);
switch (tdx_cmd.id) {
+ case KVM_TDX_INIT_VM:
+ r = tdx_td_init(kvm, &tdx_cmd);
+ break;
default:
r = -EINVAL;
goto out;
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 4b790503e43e..1e00e75b1c5e 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -12,7 +12,11 @@ struct kvm_tdx {
unsigned long tdr_pa;
unsigned long *tdcs_pa;
+ u64 attributes;
+ u64 xfam;
int hkid;
+
+ u64 tsc_offset;
};
struct vcpu_tdx {
@@ -39,6 +43,20 @@ static inline struct vcpu_tdx *to_tdx(struct kvm_vcpu *vcpu)
{
return container_of(vcpu, struct vcpu_tdx, vcpu);
}
+
+static __always_inline u64 td_tdcs_exec_read64(struct kvm_tdx *kvm_tdx, u32 field)
+{
+ struct tdx_module_output out;
+ u64 err;
+
+ err = tdh_mng_rd(kvm_tdx->tdr_pa, TDCS_EXEC(field), &out);
+ if (unlikely(err)) {
+ pr_err("TDH_MNG_RD[EXEC.0x%x] failed: 0x%llx\n", field, err);
+ return 0;
+ }
+ return out.r8;
+}
+
#else
struct kvm_tdx {
struct kvm kvm;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index af4c5bd0af1c..c0f011384934 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -565,6 +565,7 @@ struct kvm_pmu_event_filter {
/* Trust Domain eXtension sub-ioctl() commands. */
enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
+ KVM_TDX_INIT_VM,
KVM_TDX_CMD_NR_MAX,
};
@@ -610,4 +611,36 @@ struct kvm_tdx_capabilities {
struct kvm_tdx_cpuid_config cpuid_configs[0];
};
+struct kvm_tdx_init_vm {
+ __u64 attributes;
+ __u32 max_vcpus;
+ __u32 padding;
+ __u64 mrconfigid[6]; /* sha384 digest */
+ __u64 mrowner[6]; /* sha384 digest */
+ __u64 mrownerconfig[6]; /* sha348 digest */
+ union {
+ /*
+ * KVM_TDX_INIT_VM is called before vcpu creation, thus before
+ * KVM_SET_CPUID2. CPUID configurations needs to be passed.
+ *
+ * This configuration supersedes KVM_SET_CPUID{,2}.
+ * The user space VMM, e.g. qemu, should make them consistent
+ * with this values.
+ * sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES(256)
+ * = 8KB.
+ */
+ struct {
+ struct kvm_cpuid2 cpuid;
+ /* 8KB with KVM_MAX_CPUID_ENTRIES. */
+ struct kvm_cpuid_entry2 entries[];
+ };
+ /*
+ * For future extensibility.
+ * The size(struct kvm_tdx_init_vm) = 16KB.
+ * This should be enough given sizeof(TD_PARAMS) = 1024
+ */
+ __u64 reserved[2028];
+ };
+};
+
#endif /* _ASM_X86_KVM_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because TDX support introduces private mapping, add a new member in union
kvm_mmu_page_role with access functions to check the member.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 27 +++++++++++++++++++++++++++
arch/x86/kvm/mmu/mmu_internal.h | 5 +++++
arch/x86/kvm/mmu/spte.h | 6 ++++++
3 files changed, 38 insertions(+)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d441d281a6d6..38d9a972f78e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -338,7 +338,12 @@ union kvm_mmu_page_role {
unsigned ad_disabled:1;
unsigned guest_mode:1;
unsigned passthrough:1;
+#ifdef CONFIG_KVM_MMU_PRIVATE
+ unsigned is_private:1;
+ unsigned :4;
+#else
unsigned :5;
+#endif
/*
* This is left at the top of the word so that
@@ -350,6 +355,28 @@ union kvm_mmu_page_role {
};
};
+#ifdef CONFIG_KVM_MMU_PRIVATE
+static inline bool kvm_mmu_page_role_is_private(union kvm_mmu_page_role role)
+{
+ return !!role.is_private;
+}
+
+static inline void kvm_mmu_page_role_set_private(union kvm_mmu_page_role *role)
+{
+ role->is_private = 1;
+}
+#else
+static inline bool kvm_mmu_page_role_is_private(union kvm_mmu_page_role role)
+{
+ return false;
+}
+
+static inline void kvm_mmu_page_role_set_private(union kvm_mmu_page_role *role)
+{
+ WARN_ON_ONCE(1);
+}
+#endif
+
/*
* kvm_mmu_extended_role complements kvm_mmu_page_role, tracking properties
* relevant to the current MMU configuration. When loading CR0, CR4, or EFER,
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index b4fcf3eb6bd6..6c6379d4dcf9 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -143,6 +143,11 @@ static inline int kvm_mmu_page_as_id(struct kvm_mmu_page *sp)
return kvm_mmu_role_as_id(sp->role);
}
+static inline bool is_private_sp(const struct kvm_mmu_page *sp)
+{
+ return kvm_mmu_page_role_is_private(sp->role);
+}
+
static inline bool kvm_mmu_page_ad_need_write_protect(struct kvm_mmu_page *sp)
{
/*
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index a8418fd8ae9e..41973fe6bc22 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -251,6 +251,12 @@ static inline struct kvm_mmu_page *sptep_to_sp(u64 *sptep)
return to_shadow_page(__pa(sptep));
}
+static inline bool is_private_sptep(u64 *sptep)
+{
+ WARN_ON_ONCE(!sptep);
+ return is_private_sp(sptep_to_sp(sptep));
+}
+
static inline bool is_mmio_spte(struct kvm *kvm, u64 spte)
{
return (spte & shadow_mmio_mask) == kvm->arch.shadow_mmio_value &&
--
2.25.1
From: Isaku Yamahata <[email protected]>
For private GPA, CPU refers a private page table whose contents are
encrypted. The dedicated APIs to operate on it (e.g. updating/reading its
PTE entry) are used and their cost is expensive.
When KVM resolves KVM page fault, it walks the page tables. To reuse the
existing KVM MMU code and mitigate the heavy cost to directly walk private
page table, allocate one more page to copy the dummy page table for KVM MMU
code to directly walk. Resolve KVM page fault with the existing code, and
do additional operations necessary for the private page table. To
distinguish such cases, the existing KVM page table is called a shared page
table (i.e. not associated with private page table), and the page table
with private page table is called a private page table. The relationship
is depicted below.
Add a private pointer to struct kvm_mmu_page for private page table and
add helper functions to allocate/initialize/free a private page table
page.
KVM page fault |
| |
V |
-------------+---------- |
| | |
V V |
shared GPA private GPA |
| | |
V V |
shared PT root dummy PT root | private PT root
| | | |
V V | V
shared PT dummy PT ----propagate----> private PT
| | | |
| \-----------------+------\ |
| | | |
V | V V
shared guest page | private guest page
|
non-encrypted memory | encrypted memory
|
PT: page table
- Shared PT is visible to KVM and it is used by CPU.
- Private PT is used by CPU but it is invisible to KVM.
- Dummy PT is visible to KVM but not used by CPU. It is used to
propagate PT change to the actual private PT which is used by CPU.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 5 ++
arch/x86/kvm/mmu/mmu.c | 7 +++
arch/x86/kvm/mmu/mmu_internal.h | 83 +++++++++++++++++++++++++++++++--
arch/x86/kvm/mmu/tdp_mmu.c | 1 +
4 files changed, 92 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 38d9a972f78e..130e6e86f009 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -817,6 +817,11 @@ struct kvm_vcpu_arch {
struct kvm_mmu_memory_cache mmu_shadow_page_cache;
struct kvm_mmu_memory_cache mmu_shadowed_info_cache;
struct kvm_mmu_memory_cache mmu_page_header_cache;
+ /*
+ * This cache is to allocate private page table. E.g. Secure-EPT used
+ * by the TDX module.
+ */
+ struct kvm_mmu_memory_cache mmu_private_spt_cache;
/*
* QEMU userspace and the guest each have their own FPU state.
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index ce8a896a3cfa..98f20ffd12e4 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -677,6 +677,12 @@ static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu, bool maybe_indirect)
1 + PT64_ROOT_MAX_LEVEL + PTE_PREFETCH_NUM);
if (r)
return r;
+ if (kvm_gfn_shared_mask(vcpu->kvm)) {
+ r = kvm_mmu_topup_memory_cache(&vcpu->arch.mmu_private_spt_cache,
+ PT64_ROOT_MAX_LEVEL);
+ if (r)
+ return r;
+ }
r = kvm_mmu_topup_memory_cache(&vcpu->arch.mmu_shadow_page_cache,
PT64_ROOT_MAX_LEVEL);
if (r)
@@ -696,6 +702,7 @@ static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_shadow_page_cache);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_shadowed_info_cache);
+ kvm_mmu_free_memory_cache(&vcpu->arch.mmu_private_spt_cache);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache);
}
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 6c6379d4dcf9..b0d4b31557b2 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -93,7 +93,23 @@ struct kvm_mmu_page {
int root_count;
refcount_t tdp_mmu_root_count;
};
- unsigned int unsync_children;
+ union {
+ struct {
+ unsigned int unsync_children;
+ /*
+ * Number of writes since the last time traversal
+ * visited this page.
+ */
+ atomic_t write_flooding_count;
+ };
+#ifdef CONFIG_KVM_MMU_PRIVATE
+ /*
+ * Associated private shadow page table, e.g. Secure-EPT page
+ * passed to the TDX module.
+ */
+ void *private_spt;
+#endif
+ };
union {
struct kvm_rmap_head parent_ptes; /* rmap pointers to parent sptes */
tdp_ptep_t ptep;
@@ -122,9 +138,6 @@ struct kvm_mmu_page {
int clear_spte_count;
#endif
- /* Number of writes since the last time traversal visited this page. */
- atomic_t write_flooding_count;
-
#ifdef CONFIG_X86_64
/* Used for freeing the page asynchronously if it is a TDP MMU page. */
struct rcu_head rcu_head;
@@ -148,6 +161,68 @@ static inline bool is_private_sp(const struct kvm_mmu_page *sp)
return kvm_mmu_page_role_is_private(sp->role);
}
+#ifdef CONFIG_KVM_MMU_PRIVATE
+static inline void *kvm_mmu_private_spt(struct kvm_mmu_page *sp)
+{
+ return sp->private_spt;
+}
+
+static inline void kvm_mmu_init_private_spt(struct kvm_mmu_page *sp, void *private_spt)
+{
+ sp->private_spt = private_spt;
+}
+
+static inline void kvm_mmu_alloc_private_spt(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
+{
+ bool is_root = vcpu->arch.root_mmu.root_role.level == sp->role.level;
+
+ KVM_BUG_ON(!kvm_mmu_page_role_is_private(sp->role), vcpu->kvm);
+ if (is_root)
+ /*
+ * Because TDX module assigns root Secure-EPT page and set it to
+ * Secure-EPTP when TD vcpu is created, secure page table for
+ * root isn't needed.
+ */
+ sp->private_spt = NULL;
+ else {
+ /*
+ * Because the TDX module doesn't trust VMM and initializes
+ * the pages itself, KVM doesn't initialize them. Allocate
+ * pages with garbage and give them to the TDX module.
+ */
+ sp->private_spt = kvm_mmu_memory_cache_alloc(&vcpu->arch.mmu_private_spt_cache);
+ /*
+ * Because mmu_private_spt_cache is topped up before staring kvm
+ * page fault resolving, the allocation above shouldn't fail.
+ */
+ WARN_ON_ONCE(!sp->private_spt);
+ }
+}
+
+static inline void kvm_mmu_free_private_spt(struct kvm_mmu_page *sp)
+{
+ if (sp->private_spt)
+ free_page((unsigned long)sp->private_spt);
+}
+#else
+static inline void *kvm_mmu_private_spt(struct kvm_mmu_page *sp)
+{
+ return NULL;
+}
+
+static inline void kvm_mmu_init_private_spt(struct kvm_mmu_page *sp, void *private_spt)
+{
+}
+
+static inline void kvm_mmu_alloc_private_spt(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
+{
+}
+
+static inline void kvm_mmu_free_private_spt(struct kvm_mmu_page *sp)
+{
+}
+#endif
+
static inline bool kvm_mmu_page_ad_need_write_protect(struct kvm_mmu_page *sp)
{
/*
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 920d5dc633b0..4094bc080a6c 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -56,6 +56,7 @@ void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm)
static void tdp_mmu_free_sp(struct kvm_mmu_page *sp)
{
+ kvm_mmu_free_private_spt(sp);
free_page((unsigned long)sp->spt);
kmem_cache_free(mmu_page_header_cache, sp);
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
In order to reclaim TDX HKID, (i.e. when deleting guest TD), needs to call
TDH.PHYMEM.PAGE.WBINVD on all packages. If we have active TDX HKID, refuse
to offline the last online cpu to guarantee at least one CPU online per
package. Add arch callback for cpu offline.
Because TDX doesn't support suspend by the TDX 1.0 spec, this also refuses
suspend if TDs are running. If no TD is running, suspend is allowed.
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/vmx/main.c | 1 +
arch/x86/kvm/vmx/tdx.c | 43 +++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/x86_ops.h | 2 ++
arch/x86/kvm/x86.c | 5 ++++
include/linux/kvm_host.h | 1 +
virt/kvm/kvm_main.c | 12 +++++++--
8 files changed, 63 insertions(+), 3 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index c30d2d2ad686..f763981b7dbc 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -18,6 +18,7 @@ KVM_X86_OP(check_processor_compatibility)
KVM_X86_OP(hardware_enable)
KVM_X86_OP(hardware_disable)
KVM_X86_OP(hardware_unsetup)
+KVM_X86_OP_OPTIONAL_RET0(offline_cpu)
KVM_X86_OP(has_emulated_msr)
KVM_X86_OP(vcpu_after_set_cpuid)
KVM_X86_OP(is_vm_type_supported)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 15f7c0d45082..f30543caddbf 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1558,6 +1558,7 @@ struct kvm_x86_ops {
int (*hardware_enable)(void);
void (*hardware_disable)(void);
void (*hardware_unsetup)(void);
+ int (*offline_cpu)(void);
bool (*has_emulated_msr)(struct kvm *kvm, u32 index);
void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 08ed6fc8cc3d..e57b36902313 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -122,6 +122,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.check_processor_compatibility = vmx_check_processor_compat,
.hardware_unsetup = vt_hardware_unsetup,
+ .offline_cpu = tdx_offline_cpu,
.hardware_enable = vt_hardware_enable,
.hardware_disable = vmx_hardware_disable,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 496410ec6334..aeec8bcf8921 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -63,6 +63,7 @@ static struct tdx_info tdx_info;
*/
static DEFINE_MUTEX(tdx_lock);
static struct mutex *tdx_mng_key_config_lock;
+static atomic_t nr_configured_hkid;
static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
{
@@ -243,7 +244,8 @@ void tdx_mmu_release_hkid(struct kvm *kvm)
pr_err("tdh_mng_key_freeid failed. HKID %d is leaked.\n",
kvm_tdx->hkid);
return;
- }
+ } else
+ atomic_dec(&nr_configured_hkid);
free_hkid:
tdx_hkid_free(kvm_tdx);
@@ -620,6 +622,8 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params)
if (ret)
break;
}
+ if (!ret)
+ atomic_inc(&nr_configured_hkid);
cpus_read_unlock();
free_cpumask_var(packages);
if (ret)
@@ -858,3 +862,40 @@ void tdx_hardware_unsetup(void)
/* kfree accepts NULL. */
kfree(tdx_mng_key_config_lock);
}
+
+int tdx_offline_cpu(void)
+{
+ int curr_cpu = smp_processor_id();
+ cpumask_var_t packages;
+ int ret = 0;
+ int i;
+
+ /* No TD is running. Allow any cpu to be offline. */
+ if (!atomic_read(&nr_configured_hkid))
+ return 0;
+
+ /*
+ * In order to reclaim TDX HKID, (i.e. when deleting guest TD), need to
+ * call TDH.PHYMEM.PAGE.WBINVD on all packages to program all memory
+ * controller with pconfig. If we have active TDX HKID, refuse to
+ * offline the last online cpu.
+ */
+ if (!zalloc_cpumask_var(&packages, GFP_KERNEL))
+ return -ENOMEM;
+ for_each_online_cpu(i) {
+ if (i != curr_cpu)
+ cpumask_set_cpu(topology_physical_package_id(i), packages);
+ }
+ /* Check if this cpu is the last online cpu of this package. */
+ if (!cpumask_test_cpu(topology_physical_package_id(curr_cpu), packages))
+ ret = -EBUSY;
+ free_cpumask_var(packages);
+ if (ret)
+ /*
+ * Because it's hard for human operator to understand the
+ * reason, warn it.
+ */
+ pr_warn_ratelimited("TDX requires all packages to have an online CPU. "
+ "Delete all TDs in order to offline all CPUs of a package.\n");
+ return ret;
+}
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 8f87eeeab97c..544f99141f8f 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -143,6 +143,7 @@ void tdx_hardware_unsetup(void);
int tdx_hardware_enable(void);
bool tdx_is_vm_type_supported(unsigned long type);
int tdx_dev_ioctl(void __user *argp);
+int tdx_offline_cpu(void);
int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
int tdx_vm_init(struct kvm *kvm);
@@ -155,6 +156,7 @@ static inline void tdx_hardware_unsetup(void) {}
static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
+static inline int tdx_offline_cpu(void) { return 0; }
static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 89fd8074c20c..a1d5d920302b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12161,6 +12161,11 @@ void kvm_arch_hardware_disable(void)
drop_user_return_notifiers();
}
+int kvm_arch_offline_cpu(unsigned int cpu)
+{
+ return static_call(kvm_x86_offline_cpu)();
+}
+
bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
{
return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 4ae46e6f93af..115cdca6384f 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1478,6 +1478,7 @@ static inline void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) {}
int kvm_arch_hardware_enable(void);
void kvm_arch_hardware_disable(void);
#endif
+int kvm_arch_offline_cpu(unsigned int cpu);
int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu);
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu);
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3f1a55834440..f8495e27d210 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5509,13 +5509,21 @@ static void hardware_disable_nolock(void *junk)
__this_cpu_write(hardware_enabled, false);
}
+__weak int kvm_arch_offline_cpu(unsigned int cpu)
+{
+ return 0;
+}
+
static int kvm_offline_cpu(unsigned int cpu)
{
+ int r = 0;
+
mutex_lock(&kvm_lock);
- if (kvm_usage_count)
+ r = kvm_arch_offline_cpu(cpu);
+ if (!r && kvm_usage_count)
hardware_disable_nolock(NULL);
mutex_unlock(&kvm_lock);
- return 0;
+ return r;
}
static void hardware_disable_all_nolock(void)
--
2.25.1
From: Isaku Yamahata <[email protected]>
kvm_unmap_gfn_range() needs to know the reason of the callback for TDX.
mmu notifier, set memattr ioctl or restrictedmem notifier. Based on the
reason, TDX changes the behavior. For mmu notifier, it's the operation on
shared memory slot to zap shared PTE. For set memattr, it's the operation
of private<->shared conversion, zap the original PTE. For restrictedmem,
it's punching a hole of the range, zap the corresponding PTE.
Signed-off-by: Isaku Yamahata <[email protected]>
---
include/linux/kvm_host.h | 10 +++++++++-
virt/kvm/kvm_main.c | 5 ++++-
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 115cdca6384f..5a144497c930 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -257,12 +257,20 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu);
#endif
#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
+
+#define KVM_GFN_RANGE_FLAGS_RESTRICTED_MEM BIT(0)
+#define KVM_GFN_RANGE_FLAGS_SET_MEM_ATTR BIT(1)
+
struct kvm_gfn_range {
struct kvm_memory_slot *slot;
gfn_t start;
gfn_t end;
- pte_t pte;
+ union {
+ pte_t pte;
+ u64 attrs;
+ };
bool may_block;
+ unsigned int flags;
};
bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range);
bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 87400796df6e..d6db3f19ad74 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -626,6 +626,7 @@ static __always_inline int __kvm_handle_hva_range(struct kvm *kvm,
gfn_range.start = hva_to_gfn_memslot(hva_start, slot);
gfn_range.end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, slot);
gfn_range.slot = slot;
+ gfn_range.flags = 0;
if (!locked) {
locked = true;
@@ -957,6 +958,7 @@ static int restrictedmem_get_gfn_range(struct kvm_memory_slot *slot,
range->slot = slot;
range->pte = __pte(0);
range->may_block = true;
+ range->flags = KVM_GFN_RANGE_FLAGS_RESTRICTED_MEM;
return 0;
}
@@ -2557,8 +2559,9 @@ static void kvm_mem_attrs_changed(struct kvm *kvm, unsigned long attrs,
bool flush = false;
int i;
- gfn_range.pte = __pte(0);
+ gfn_range.attrs = attrs;
gfn_range.may_block = true;
+ gfn_range.flags = KVM_GFN_RANGE_FLAGS_SET_MEM_ATTR;
for (i = 0; i < kvm_arch_nr_memslot_as_ids(kvm); i++) {
slots = __kvm_memslots(kvm, i);
--
2.25.1
From: Sean Christopherson <[email protected]>
TDX supports only write-back(WB) memory type for private memory
architecturally so that (virtualized) memory type change doesn't make sense
for private memory. Also currently, page migration isn't supported for TDX
yet. (TDX architecturally supports page migration. it's KVM and kernel
implementation issue.)
Regarding memory type change (mtrr virtualization and lapic page mapping
change), pages are zapped by kvm_zap_gfn_range(). On the next KVM page
fault, the SPTE entry with a new memory type for the page is populated.
Regarding page migration, pages are zapped by the mmu notifier. On the next
KVM page fault, the new migrated page is populated. Don't zap private
pages on unmapping for those two cases.
When deleting/moving a KVM memory slot, zap private pages. Typically
tearing down VM. Don't invalidate private page tables. i.e. zap only leaf
SPTEs for KVM mmu that has a shared bit mask. The existing
kvm_tdp_mmu_invalidate_all_roots() depends on role.invalid with read-lock
of mmu_lock so that other vcpu can operate on KVM mmu concurrently. It
marks the root page table invalid and zaps SPTEs of the root page
tables. The TDX module doesn't allow to unlink a protected root page table
from the hardware and then allocate a new one for it. i.e. replacing a
protected root page table. Instead, zap only leaf SPTEs for KVM mmu with a
shared bit mask set.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/mmu.c | 81 ++++++++++++++++++++++++++++++++++++--
arch/x86/kvm/mmu/tdp_mmu.c | 24 ++++++++---
arch/x86/kvm/mmu/tdp_mmu.h | 5 ++-
3 files changed, 99 insertions(+), 11 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 98f20ffd12e4..fb114effd94b 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -1600,8 +1600,28 @@ bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
if (kvm_memslots_have_rmaps(kvm))
flush = kvm_handle_gfn_range(kvm, range, kvm_zap_rmap);
- if (tdp_mmu_enabled)
- flush = kvm_tdp_mmu_unmap_gfn_range(kvm, range, flush);
+ if (tdp_mmu_enabled) {
+ bool zap_private;
+
+ if (range->flags & KVM_GFN_RANGE_FLAGS_RESTRICTED_MEM) {
+ WARN_ON_ONCE(!kvm_slot_can_be_private(range->slot));
+ /*
+ * For private slot, the callback is triggered
+ * via PUNCH_HOLE (fallocate(PUNCH_HOLE) or truncate).
+ * private-shared conversion is done by
+ * KVM_SET_MEMORY_ATTRIBUTES.
+ */
+ zap_private = true;
+ } else if (range->flags & KVM_GFN_RANGE_FLAGS_SET_MEM_ATTR)
+ zap_private = !(range->attrs & KVM_MEMORY_ATTRIBUTE_PRIVATE);
+ else
+ /*
+ * For now private pages are pinned during VM's life
+ * time.
+ */
+ zap_private = false;
+ flush = kvm_tdp_mmu_unmap_gfn_range(kvm, range, flush, zap_private);
+ }
return flush;
}
@@ -6183,11 +6203,54 @@ static bool kvm_has_zapped_obsolete_pages(struct kvm *kvm)
return unlikely(!list_empty_careful(&kvm->arch.zapped_obsolete_pages));
}
+static void kvm_mmu_zap_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
+{
+ bool flush = false;
+
+ write_lock(&kvm->mmu_lock);
+
+ /*
+ * Zapping non-leaf SPTEs, a.k.a. not-last SPTEs, isn't required, worst
+ * case scenario we'll have unused shadow pages lying around until they
+ * are recycled due to age or when the VM is destroyed.
+ */
+ if (tdp_mmu_enabled) {
+ struct kvm_gfn_range range = {
+ .slot = slot,
+ .start = slot->base_gfn,
+ .end = slot->base_gfn + slot->npages,
+ .may_block = true,
+ };
+
+ /*
+ * this handles both private gfn and shared gfn.
+ * All private page should be zapped on memslot deletion.
+ */
+ flush = kvm_tdp_mmu_unmap_gfn_range(kvm, &range, flush, true);
+ } else {
+ /* TDX supports only TDP-MMU case. */
+ WARN_ON_ONCE(1);
+ flush = true;
+ }
+ if (flush)
+ kvm_flush_remote_tlbs(kvm);
+
+ write_unlock(&kvm->mmu_lock);
+}
+
static void kvm_mmu_invalidate_zap_pages_in_memslot(struct kvm *kvm,
struct kvm_memory_slot *slot,
struct kvm_page_track_notifier_node *node)
{
- kvm_mmu_zap_all_fast(kvm);
+ if (kvm_gfn_shared_mask(kvm))
+ /*
+ * Secure-EPT requires to release PTs from the leaf. The
+ * optimization to zap root PT first with child PT doesn't
+ * work.
+ */
+ kvm_mmu_zap_memslot(kvm, slot);
+ else
+ kvm_mmu_zap_all_fast(kvm);
}
int kvm_mmu_init_vm(struct kvm *kvm)
@@ -6295,8 +6358,18 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
if (tdp_mmu_enabled) {
for (i = 0; i < kvm_arch_nr_memslot_as_ids(kvm); i++)
+ /*
+ * zap_private = true. Zap both private/shared pages.
+ *
+ * kvm_zap_gfn_range() is used when MTRR or PAT memory
+ * type was changed. Later on the next kvm page fault,
+ * populate it with updated spte entry.
+ * Because only WB is supported for private pages, don't
+ * care of private pages.
+ */
flush = kvm_tdp_mmu_zap_leafs(kvm, i, gfn_start,
- gfn_end, true, flush);
+ gfn_end, true, flush,
+ false);
}
if (flush)
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 4094bc080a6c..3e2575128739 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -931,7 +931,8 @@ bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
* operation can cause a soft lockup.
*/
static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
- gfn_t start, gfn_t end, bool can_yield, bool flush)
+ gfn_t start, gfn_t end, bool can_yield, bool flush,
+ bool zap_private)
{
struct tdp_iter iter;
@@ -939,6 +940,10 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
lockdep_assert_held_write(&kvm->mmu_lock);
+ WARN_ON_ONCE(zap_private && !is_private_sp(root));
+ if (!zap_private && is_private_sp(root))
+ return false;
+
rcu_read_lock();
for_each_tdp_pte_min_level(iter, root, PG_LEVEL_4K, start, end) {
@@ -971,12 +976,13 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
* more SPTEs were zapped since the MMU lock was last acquired.
*/
bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, int as_id, gfn_t start, gfn_t end,
- bool can_yield, bool flush)
+ bool can_yield, bool flush, bool zap_private)
{
struct kvm_mmu_page *root;
for_each_tdp_mmu_root_yield_safe(kvm, root, as_id)
- flush = tdp_mmu_zap_leafs(kvm, root, start, end, can_yield, flush);
+ flush = tdp_mmu_zap_leafs(kvm, root, start, end, can_yield, flush,
+ zap_private && is_private_sp(root));
return flush;
}
@@ -1036,6 +1042,12 @@ void kvm_tdp_mmu_invalidate_all_roots(struct kvm *kvm)
lockdep_assert_held_write(&kvm->mmu_lock);
list_for_each_entry(root, &kvm->arch.tdp_mmu_roots, link) {
+ /*
+ * Skip private root since private page table
+ * is only torn down when VM is destroyed.
+ */
+ if (is_private_sp(root))
+ continue;
if (!root->role.invalid &&
!WARN_ON_ONCE(!kvm_tdp_mmu_get_root(root))) {
root->role.invalid = true;
@@ -1219,11 +1231,13 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
return ret;
}
+/* Used by mmu notifier via kvm_unmap_gfn_range() */
bool kvm_tdp_mmu_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range,
- bool flush)
+ bool flush, bool zap_private)
{
return kvm_tdp_mmu_zap_leafs(kvm, range->slot->as_id, range->start,
- range->end, range->may_block, flush);
+ range->end, range->may_block, flush,
+ zap_private);
}
typedef bool (*tdp_handler_t)(struct kvm *kvm, struct tdp_iter *iter,
diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h
index 0a63b1afabd3..b32cbdf2f675 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.h
+++ b/arch/x86/kvm/mmu/tdp_mmu.h
@@ -21,7 +21,8 @@ void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root,
bool shared);
bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, int as_id, gfn_t start,
- gfn_t end, bool can_yield, bool flush);
+ gfn_t end, bool can_yield, bool flush,
+ bool zap_private);
bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp);
void kvm_tdp_mmu_zap_all(struct kvm *kvm);
void kvm_tdp_mmu_invalidate_all_roots(struct kvm *kvm);
@@ -30,7 +31,7 @@ void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm);
int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault);
bool kvm_tdp_mmu_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range,
- bool flush);
+ bool flush, bool zap_private);
bool kvm_tdp_mmu_age_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range);
bool kvm_tdp_mmu_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
bool kvm_tdp_mmu_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TD vcpu
creation/destruction.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index 098150da6ea2..25082e9c0b20 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -9,7 +9,7 @@ Layer status
What qemu can do
----------------
- TDX VM TYPE is exposed to Qemu.
-- Qemu can try to create VM of TDX VM type and then fails.
+- Qemu can create/destroy guest of TDX vm type.
Patch Layer status
------------------
@@ -17,8 +17,8 @@ Patch Layer status
* TDX, VMX coexistence: Applied
* TDX architectural definitions: Applied
-* TD VM creation/destruction: Applying
-* TD vcpu creation/destruction: Not yet
+* TD VM creation/destruction: Applied
+* TD vcpu creation/destruction: Applying
* TDX EPT violation: Not yet
* TD finalization: Not yet
* TD vcpu enter/exit: Not yet
--
2.25.1
From: Isaku Yamahata <[email protected]>
The next step of TDX guest creation is to create vcpu. Allocate TDX vcpu
structures, initialize it that doesn't require TDX SEAMCALL. TDX specific
vcpu initialization will be implemented as independent KVM_TDX_INIT_VCPU
so that when error occurs it's easy to determine which component has the
issue, KVM or TDX.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Changes v11 -> v12:
- add more comments in tdx_vcpu_reset().
- use KVM_BUG_ON()
Changes v10 -> v11:
- NULL check of kvmalloc_array() in tdx_vcpu_reset. Move it to
tdx_vcpu_create()
---
arch/x86/kvm/vmx/main.c | 44 ++++++++++++++++++++++++++++++----
arch/x86/kvm/vmx/tdx.c | 49 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 10 ++++++++
arch/x86/kvm/x86.c | 2 ++
4 files changed, 101 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index e57b36902313..e9fd4e80b67d 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -97,6 +97,42 @@ static void vt_vm_free(struct kvm *kvm)
tdx_vm_free(kvm);
}
+static int vt_vcpu_precreate(struct kvm *kvm)
+{
+ if (is_td(kvm))
+ return 0;
+
+ return vmx_vcpu_precreate(kvm);
+}
+
+static int vt_vcpu_create(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_vcpu_create(vcpu);
+
+ return vmx_vcpu_create(vcpu);
+}
+
+static void vt_vcpu_free(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_vcpu_free(vcpu);
+ return;
+ }
+
+ vmx_vcpu_free(vcpu);
+}
+
+static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_vcpu_reset(vcpu, init_event);
+ return;
+ }
+
+ vmx_vcpu_reset(vcpu, init_event);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -137,10 +173,10 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vm_destroy = vt_vm_destroy,
.vm_free = vt_vm_free,
- .vcpu_precreate = vmx_vcpu_precreate,
- .vcpu_create = vmx_vcpu_create,
- .vcpu_free = vmx_vcpu_free,
- .vcpu_reset = vmx_vcpu_reset,
+ .vcpu_precreate = vt_vcpu_precreate,
+ .vcpu_create = vt_vcpu_create,
+ .vcpu_free = vt_vcpu_free,
+ .vcpu_reset = vt_vcpu_reset,
.prepare_switch_to_guest = vmx_prepare_switch_to_guest,
.vcpu_load = vmx_vcpu_load,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index aeec8bcf8921..4fec35f4f5b2 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -321,6 +321,55 @@ int tdx_vm_init(struct kvm *kvm)
return 0;
}
+int tdx_vcpu_create(struct kvm_vcpu *vcpu)
+{
+ /*
+ * On cpu creation, cpuid entry is blank. Forcibly enable
+ * X2APIC feature to allow X2APIC.
+ * Because vcpu_reset() can't return error, allocation is done here.
+ */
+ WARN_ON_ONCE(vcpu->arch.cpuid_entries);
+ WARN_ON_ONCE(vcpu->arch.cpuid_nent);
+
+ /* TDX only supports x2APIC, which requires an in-kernel local APIC. */
+ if (!vcpu->arch.apic)
+ return -EINVAL;
+
+ fpstate_set_confidential(&vcpu->arch.guest_fpu);
+
+ vcpu->arch.efer = EFER_SCE | EFER_LME | EFER_LMA | EFER_NX;
+
+ vcpu->arch.cr0_guest_owned_bits = -1ul;
+ vcpu->arch.cr4_guest_owned_bits = -1ul;
+
+ vcpu->arch.tsc_offset = to_kvm_tdx(vcpu->kvm)->tsc_offset;
+ vcpu->arch.l1_tsc_offset = vcpu->arch.tsc_offset;
+ vcpu->arch.guest_state_protected =
+ !(to_kvm_tdx(vcpu->kvm)->attributes & TDX_TD_ATTRIBUTE_DEBUG);
+
+ return 0;
+}
+
+void tdx_vcpu_free(struct kvm_vcpu *vcpu)
+{
+ /* This is stub for now. More logic will come. */
+}
+
+void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
+{
+
+ /* Ignore INIT silently because TDX doesn't support INIT event. */
+ if (init_event)
+ return;
+
+ /* This is stub for now. More logic will come here. */
+
+ /*
+ * Don't update mp_state to runnable because more initialization
+ * is needed by TDX_VCPU_INIT.
+ */
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 544f99141f8f..1669c95d8249 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -149,7 +149,12 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
int tdx_vm_init(struct kvm *kvm);
void tdx_mmu_release_hkid(struct kvm *kvm);
void tdx_vm_free(struct kvm *kvm);
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
+
+int tdx_vcpu_create(struct kvm_vcpu *vcpu);
+void tdx_vcpu_free(struct kvm_vcpu *vcpu);
+void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline void tdx_hardware_unsetup(void) {}
@@ -163,7 +168,12 @@ static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
static inline void tdx_vm_free(struct kvm *kvm) {}
+
static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
+
+static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
+static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
+static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a1d5d920302b..0ba15a9e126f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -496,6 +496,7 @@ int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
kvm_recalculate_apic_map(vcpu->kvm);
return 0;
}
+EXPORT_SYMBOL_GPL(kvm_set_apic_base);
/*
* Handle a fault on a hardware virtualization (VMX or SVM) instruction.
@@ -12170,6 +12171,7 @@ bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
{
return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id;
}
+EXPORT_SYMBOL_GPL(kvm_vcpu_is_reset_bsp);
bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
{
--
2.25.1
From: Isaku Yamahata <[email protected]>
TD guest vcpu needs TDX specific initialization before running. Repurpose
KVM_MEMORY_ENCRYPT_OP to vcpu-scope, add a new sub-command
KVM_TDX_INIT_VCPU, and implement the callback for it.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/include/uapi/asm/kvm.h | 1 +
arch/x86/kvm/vmx/main.c | 9 ++
arch/x86/kvm/vmx/tdx.c | 171 +++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 7 ++
arch/x86/kvm/vmx/x86_ops.h | 4 +
arch/x86/kvm/x86.c | 6 +
tools/arch/x86/include/uapi/asm/kvm.h | 1 +
9 files changed, 200 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index f763981b7dbc..d29e16098c30 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -124,6 +124,7 @@ KVM_X86_OP(enable_smi_window)
#endif
KVM_X86_OP(dev_mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
+KVM_X86_OP_OPTIONAL(vcpu_mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_register_region)
KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
KVM_X86_OP_OPTIONAL(vm_copy_enc_context_from)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f30543caddbf..42fa696a04ea 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1726,6 +1726,7 @@ struct kvm_x86_ops {
int (*dev_mem_enc_ioctl)(void __user *argp);
int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
+ int (*vcpu_mem_enc_ioctl)(struct kvm_vcpu *vcpu, void __user *argp);
int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
int (*mem_enc_unregister_region)(struct kvm *kvm, struct kvm_enc_region *argp);
int (*vm_copy_enc_context_from)(struct kvm *kvm, unsigned int source_fd);
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 68e8d544afe5..da7078cd7d7d 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -566,6 +566,7 @@ struct kvm_pmu_event_filter {
enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
KVM_TDX_INIT_VM,
+ KVM_TDX_INIT_VCPU,
KVM_TDX_CMD_NR_MAX,
};
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index e9fd4e80b67d..57240d6ab97a 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -141,6 +141,14 @@ static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
return tdx_vm_ioctl(kvm, argp);
}
+static int vt_vcpu_mem_enc_ioctl(struct kvm_vcpu *vcpu, void __user *argp)
+{
+ if (!is_td_vcpu(vcpu))
+ return -EINVAL;
+
+ return tdx_vcpu_ioctl(vcpu, argp);
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
( \
BIT(APICV_INHIBIT_REASON_DISABLE)| \
@@ -300,6 +308,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.dev_mem_enc_ioctl = tdx_dev_ioctl,
.mem_enc_ioctl = vt_mem_enc_ioctl,
+ .vcpu_mem_enc_ioctl = vt_vcpu_mem_enc_ioctl,
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 4fec35f4f5b2..1415ab60ce2c 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -48,6 +48,7 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
struct tdx_info {
u8 nr_tdcs_pages;
+ u8 nr_tdvpx_pages;
};
/* Info about the TDX module. */
@@ -70,6 +71,11 @@ static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
}
+static inline bool is_td_vcpu_created(struct vcpu_tdx *tdx)
+{
+ return tdx->tdvpr_pa;
+}
+
static inline bool is_td_created(struct kvm_tdx *kvm_tdx)
{
return kvm_tdx->tdr_pa;
@@ -86,6 +92,11 @@ static inline bool is_hkid_assigned(struct kvm_tdx *kvm_tdx)
return kvm_tdx->hkid > 0;
}
+static inline bool is_td_finalized(struct kvm_tdx *kvm_tdx)
+{
+ return kvm_tdx->finalized;
+}
+
int tdx_hardware_enable(void)
{
return tdx_cpu_enable();
@@ -352,7 +363,28 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
void tdx_vcpu_free(struct kvm_vcpu *vcpu)
{
- /* This is stub for now. More logic will come. */
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ int i;
+
+ /*
+ * This methods can be called when vcpu allocation/initialization
+ * failed. So it's possible that hkid, tdvpx and tdvpr are not assigned
+ * yet.
+ */
+ if (is_hkid_assigned(to_kvm_tdx(vcpu->kvm))) {
+ WARN_ON_ONCE(tdx->tdvpx_pa);
+ WARN_ON_ONCE(tdx->tdvpr_pa);
+ return;
+ }
+
+ if (tdx->tdvpx_pa) {
+ for (i = 0; i < tdx_info.nr_tdvpx_pages; i++)
+ tdx_reclaim_td_page(tdx->tdvpx_pa[i]);
+ kfree(tdx->tdvpx_pa);
+ tdx->tdvpx_pa = NULL;
+ }
+ tdx_reclaim_td_page(tdx->tdvpr_pa);
+ tdx->tdvpr_pa = 0;
}
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
@@ -361,6 +393,8 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
/* Ignore INIT silently because TDX doesn't support INIT event. */
if (init_event)
return;
+ if (KVM_BUG_ON(is_td_vcpu_created(to_tdx(vcpu)), vcpu->kvm))
+ return;
/* This is stub for now. More logic will come here. */
@@ -828,6 +862,136 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
return r;
}
+/* VMM can pass one 64bit auxiliary data to vcpu via RCX for guest BIOS. */
+static int tdx_td_vcpu_init(struct kvm_vcpu *vcpu, u64 vcpu_rcx)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ unsigned long *tdvpx_pa = NULL;
+ unsigned long tdvpr_pa;
+ unsigned long va;
+ int ret, i;
+ u64 err;
+
+ if (is_td_vcpu_created(tdx))
+ return -EINVAL;
+
+ /*
+ * vcpu_free method frees allocated pages. Avoid partial setup so
+ * that the method can't handle it.
+ */
+ va = __get_free_page(GFP_KERNEL_ACCOUNT);
+ if (!va)
+ return -ENOMEM;
+ tdvpr_pa = __pa(va);
+
+ tdvpx_pa = kcalloc(tdx_info.nr_tdvpx_pages, sizeof(*tdx->tdvpx_pa),
+ GFP_KERNEL_ACCOUNT);
+ if (!tdvpx_pa) {
+ ret = -ENOMEM;
+ goto free_tdvpr;
+ }
+ for (i = 0; i < tdx_info.nr_tdvpx_pages; i++) {
+ va = __get_free_page(GFP_KERNEL_ACCOUNT);
+ if (!va) {
+ ret = -ENOMEM;
+ goto free_tdvpx;
+ }
+ tdvpx_pa[i] = __pa(va);
+ }
+
+ err = tdh_vp_create(kvm_tdx->tdr_pa, tdvpr_pa);
+ if (KVM_BUG_ON(err, vcpu->kvm)) {
+ ret = -EIO;
+ pr_tdx_error(TDH_VP_CREATE, err, NULL);
+ goto free_tdvpx;
+ }
+ tdx->tdvpr_pa = tdvpr_pa;
+
+ tdx->tdvpx_pa = tdvpx_pa;
+ for (i = 0; i < tdx_info.nr_tdvpx_pages; i++) {
+ err = tdh_vp_addcx(tdx->tdvpr_pa, tdvpx_pa[i]);
+ if (KVM_BUG_ON(err, vcpu->kvm)) {
+ pr_tdx_error(TDH_VP_ADDCX, err, NULL);
+ for (; i < tdx_info.nr_tdvpx_pages; i++) {
+ free_page((unsigned long)__va(tdvpx_pa[i]));
+ tdvpx_pa[i] = 0;
+ }
+ /* vcpu_free method frees TDVPX and TDR donated to TDX */
+ return -EIO;
+ }
+ }
+
+ err = tdh_vp_init(tdx->tdvpr_pa, vcpu_rcx);
+ if (KVM_BUG_ON(err, vcpu->kvm)) {
+ pr_tdx_error(TDH_VP_INIT, err, NULL);
+ return -EIO;
+ }
+
+ vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
+ return 0;
+
+free_tdvpx:
+ for (i = 0; i < tdx_info.nr_tdvpx_pages; i++) {
+ if (tdvpx_pa[i])
+ free_page((unsigned long)__va(tdvpx_pa[i]));
+ tdvpx_pa[i] = 0;
+ }
+ kfree(tdvpx_pa);
+ tdx->tdvpx_pa = NULL;
+free_tdvpr:
+ if (tdvpr_pa)
+ free_page((unsigned long)__va(tdvpr_pa));
+ tdx->tdvpr_pa = 0;
+
+ return ret;
+}
+
+int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp)
+{
+ struct msr_data apic_base_msr;
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ struct kvm_tdx_cmd cmd;
+ int ret;
+
+ if (tdx->initialized)
+ return -EINVAL;
+
+ if (!is_hkid_assigned(kvm_tdx) || is_td_finalized(kvm_tdx))
+ return -EINVAL;
+
+ if (copy_from_user(&cmd, argp, sizeof(cmd)))
+ return -EFAULT;
+
+ if (cmd.error || cmd.unused)
+ return -EINVAL;
+
+ /* Currently only KVM_TDX_INTI_VCPU is defined for vcpu operation. */
+ if (cmd.flags || cmd.id != KVM_TDX_INIT_VCPU)
+ return -EINVAL;
+
+ /*
+ * As TDX requires X2APIC, set local apic mode to X2APIC. User space
+ * VMM, e.g. qemu, is required to set CPUID[0x1].ecx.X2APIC=1 by
+ * KVM_SET_CPUID2. Otherwise kvm_set_apic_base() will fail.
+ */
+ apic_base_msr = (struct msr_data) {
+ .host_initiated = true,
+ .data = APIC_DEFAULT_PHYS_BASE | LAPIC_MODE_X2APIC |
+ (kvm_vcpu_is_reset_bsp(vcpu) ? MSR_IA32_APICBASE_BSP : 0),
+ };
+ if (kvm_set_apic_base(vcpu, &apic_base_msr))
+ return -EINVAL;
+
+ ret = tdx_td_vcpu_init(vcpu, (u64)cmd.data);
+ if (ret)
+ return ret;
+
+ tdx->initialized = true;
+ return 0;
+}
+
static int __init tdx_module_setup(void)
{
const struct tdsysinfo_struct *tdsysinfo;
@@ -846,6 +1010,11 @@ static int __init tdx_module_setup(void)
WARN_ON(tdsysinfo->num_cpuid_config > TDX_MAX_NR_CPUID_CONFIGS);
tdx_info = (struct tdx_info) {
.nr_tdcs_pages = tdsysinfo->tdcs_base_size / PAGE_SIZE,
+ /*
+ * TDVPS = TDVPR(4K page) + TDVPX(multiple 4K pages).
+ * -1 for TDVPR.
+ */
+ .nr_tdvpx_pages = tdsysinfo->tdvps_base_size / PAGE_SIZE - 1,
};
pr_info("TDX is supported.\n");
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 5728820fed5e..5fa4d3198873 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -17,12 +17,19 @@ struct kvm_tdx {
u64 xfam;
int hkid;
+ bool finalized;
+
u64 tsc_offset;
};
struct vcpu_tdx {
struct kvm_vcpu vcpu;
+ unsigned long tdvpr_pa;
+ unsigned long *tdvpx_pa;
+
+ bool initialized;
+
/*
* Dummy to make pmu_intel not corrupt memory.
* TODO: Support PMU for TDX. Future work.
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 1669c95d8249..92af5d2d5db7 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -155,6 +155,8 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
+
+int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline void tdx_hardware_unsetup(void) {}
@@ -174,6 +176,8 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP
static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
+
+static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0ba15a9e126f..a0960b468c74 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6002,6 +6002,12 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
case KVM_SET_DEVICE_ATTR:
r = kvm_vcpu_ioctl_device_attr(vcpu, ioctl, argp);
break;
+ case KVM_MEMORY_ENCRYPT_OP:
+ r = -ENOTTY;
+ if (!kvm_x86_ops.vcpu_mem_enc_ioctl)
+ goto out;
+ r = kvm_x86_ops.vcpu_mem_enc_ioctl(vcpu, argp);
+ break;
default:
r = -EINVAL;
}
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index c0f011384934..0f88e32d02a8 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -566,6 +566,7 @@ struct kvm_pmu_event_filter {
enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
KVM_TDX_INIT_VM,
+ KVM_TDX_INIT_VCPU,
KVM_TDX_CMD_NR_MAX,
};
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDP MMU allows tdp_mmu_set_spte_atomic() and tdp_mmu_zap_spte_atomic() to
return -EBUSY or -EAGAIN error. The caller must check the return value and
retry. Sprinkle __must_check to guarantee it.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/tdp_mmu.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 3e2575128739..67bc6084b497 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -628,9 +628,9 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
* no side-effects other than setting iter->old_spte to the last
* known value of the spte.
*/
-static inline int tdp_mmu_set_spte_atomic(struct kvm *kvm,
- struct tdp_iter *iter,
- u64 new_spte)
+static inline int __must_check tdp_mmu_set_spte_atomic(struct kvm *kvm,
+ struct tdp_iter *iter,
+ u64 new_spte)
{
u64 *sptep = rcu_dereference(iter->sptep);
@@ -658,8 +658,8 @@ static inline int tdp_mmu_set_spte_atomic(struct kvm *kvm,
return 0;
}
-static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
- struct tdp_iter *iter)
+static inline int __must_check tdp_mmu_zap_spte_atomic(struct kvm *kvm,
+ struct tdp_iter *iter)
{
int ret;
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of KVM MMU GPA
shared bits.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index 25082e9c0b20..8b8186e7bfeb 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -10,6 +10,7 @@ What qemu can do
----------------
- TDX VM TYPE is exposed to Qemu.
- Qemu can create/destroy guest of TDX vm type.
+- Qemu can create/destroy vcpu of TDX vm type.
Patch Layer status
------------------
@@ -18,12 +19,12 @@ Patch Layer status
* TDX, VMX coexistence: Applied
* TDX architectural definitions: Applied
* TD VM creation/destruction: Applied
-* TD vcpu creation/destruction: Applying
+* TD vcpu creation/destruction: Applied
* TDX EPT violation: Not yet
* TD finalization: Not yet
* TD vcpu enter/exit: Not yet
* TD vcpu interrupts/exit/hypercall: Not yet
-* KVM MMU GPA shared bits: Not yet
+* KVM MMU GPA shared bits: Applying
* KVM TDP refactoring for TDX: Not yet
* KVM TDP MMU hooks: Not yet
--
2.25.1
From: Isaku Yamahata <[email protected]>
Allocate protected page table for private page table, and add hooks to
operate on protected page table. This patch adds allocation/free of
protected page tables and hooks. When calling hooks to update SPTE entry,
freeze the entry, call hooks and unfreeze the entry to allow concurrent
updates on page tables. Which is the advantage of TDP MMU. As
kvm_gfn_shared_mask() returns false always, those hooks aren't called yet
with this patch.
When the faulting GPA is private, the KVM fault is called private. When
resolving private KVM fault, allocate protected page table and call hooks
to operate on protected page table. On the change of the private PTE entry,
invoke kvm_x86_ops hook in __handle_changed_spte() to propagate the change
to protected page table. The following depicts the relationship.
private KVM page fault |
| |
V |
private GPA | CPU protected EPTP
| | |
V | V
private PT root | protected PT root
| | |
V | V
private PT --hook to propagate-->protected PT
| | |
\--------------------+------\ |
| | |
| V V
| private guest page
|
|
non-encrypted memory | encrypted memory
|
PT: page table
The existing KVM TDP MMU code uses atomic update of SPTE. On populating
the EPT entry, atomically set the entry. However, it requires TLB
shootdown to zap SPTE. To address it, the entry is frozen with the special
SPTE value that clears the present bit. After the TLB shootdown, the entry
is set to the eventual value (unfreeze).
For protected page table, hooks are called to update protected page table
in addition to direct access to the private SPTE. For the zapping case, it
works to freeze the SPTE. It can call hooks in addition to TLB shootdown.
For populating the private SPTE entry, there can be a race condition
without further protection
vcpu 1: populating 2M private SPTE
vcpu 2: populating 4K private SPTE
vcpu 2: TDX SEAMCALL to update 4K protected SPTE => error
vcpu 1: TDX SEAMCALL to update 2M protected SPTE
To avoid the race, the frozen SPTE is utilized. Instead of atomic update
of the private entry, freeze the entry, call the hook that update protected
SPTE, set the entry to the final value.
Support 4K page only at this stage. 2M page support can be done in future
patches.
Co-developed-by: Kai Huang <[email protected]>
Signed-off-by: Kai Huang <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
Changes v11 -> v12
- Split tdp mmu hooks at tdp_mmu_set_spte_atomic() for populating and
__handle_changed_spte() for zapping.
---
arch/x86/include/asm/kvm-x86-ops.h | 5 +
arch/x86/include/asm/kvm_host.h | 11 ++
arch/x86/kvm/mmu/mmu.c | 13 +-
arch/x86/kvm/mmu/mmu_internal.h | 21 +-
arch/x86/kvm/mmu/tdp_iter.h | 2 +-
arch/x86/kvm/mmu/tdp_mmu.c | 300 +++++++++++++++++++++++++----
arch/x86/kvm/mmu/tdp_mmu.h | 2 +-
virt/kvm/kvm_main.c | 1 +
8 files changed, 313 insertions(+), 42 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index d29e16098c30..2681300ce142 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -96,6 +96,11 @@ KVM_X86_OP_OPTIONAL_RET0(set_tss_addr)
KVM_X86_OP_OPTIONAL_RET0(set_identity_map_addr)
KVM_X86_OP_OPTIONAL_RET0(get_mt_mask)
KVM_X86_OP(load_mmu_pgd)
+KVM_X86_OP_OPTIONAL(link_private_spt)
+KVM_X86_OP_OPTIONAL(free_private_spt)
+KVM_X86_OP_OPTIONAL(set_private_spte)
+KVM_X86_OP_OPTIONAL(remove_private_spte)
+KVM_X86_OP_OPTIONAL(zap_private_spte)
KVM_X86_OP(has_wbinvd_exit)
KVM_X86_OP(get_l2_tsc_offset)
KVM_X86_OP(get_l2_tsc_multiplier)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 130e6e86f009..7b735c3e7d8c 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -470,6 +470,7 @@ struct kvm_mmu {
struct kvm_mmu_page *sp);
void (*invlpg)(struct kvm_vcpu *vcpu, gva_t gva, hpa_t root_hpa);
struct kvm_mmu_root_info root;
+ hpa_t private_root_hpa;
union kvm_cpu_role cpu_role;
union kvm_mmu_page_role root_role;
@@ -1707,6 +1708,16 @@ struct kvm_x86_ops {
void (*load_mmu_pgd)(struct kvm_vcpu *vcpu, hpa_t root_hpa,
int root_level);
+ int (*link_private_spt)(struct kvm *kvm, gfn_t gfn, enum pg_level level,
+ void *private_spt);
+ int (*free_private_spt)(struct kvm *kvm, gfn_t gfn, enum pg_level level,
+ void *private_spt);
+ int (*set_private_spte)(struct kvm *kvm, gfn_t gfn, enum pg_level level,
+ kvm_pfn_t pfn);
+ int (*remove_private_spte)(struct kvm *kvm, gfn_t gfn, enum pg_level level,
+ kvm_pfn_t pfn);
+ int (*zap_private_spte)(struct kvm *kvm, gfn_t gfn, enum pg_level level);
+
bool (*has_wbinvd_exit)(void);
u64 (*get_l2_tsc_offset)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index fb114effd94b..3d68da838f94 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3689,7 +3689,12 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu)
goto out_unlock;
if (tdp_mmu_enabled) {
- root = kvm_tdp_mmu_get_vcpu_root_hpa(vcpu);
+ if (kvm_gfn_shared_mask(vcpu->kvm) &&
+ !VALID_PAGE(mmu->private_root_hpa)) {
+ root = kvm_tdp_mmu_get_vcpu_root_hpa(vcpu, true);
+ mmu->private_root_hpa = root;
+ }
+ root = kvm_tdp_mmu_get_vcpu_root_hpa(vcpu, false);
mmu->root.hpa = root;
} else if (shadow_root_level >= PT64_ROOT_4LEVEL) {
root = mmu_alloc_root(vcpu, 0, 0, shadow_root_level);
@@ -5997,6 +6002,7 @@ static int __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
mmu->root.hpa = INVALID_PAGE;
mmu->root.pgd = 0;
+ mmu->private_root_hpa = INVALID_PAGE;
for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
mmu->prev_roots[i] = KVM_MMU_ROOT_INFO_INVALID;
@@ -6223,7 +6229,7 @@ static void kvm_mmu_zap_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
};
/*
- * this handles both private gfn and shared gfn.
+ * This handles both private gfn and shared gfn.
* All private page should be zapped on memslot deletion.
*/
flush = kvm_tdp_mmu_unmap_gfn_range(kvm, &range, flush, true);
@@ -7042,6 +7048,9 @@ int kvm_mmu_vendor_module_init(void)
void kvm_mmu_destroy(struct kvm_vcpu *vcpu)
{
kvm_mmu_unload(vcpu);
+ if (tdp_mmu_enabled)
+ mmu_free_root_page(vcpu->kvm, &vcpu->arch.mmu->private_root_hpa,
+ NULL);
free_mmu_pages(&vcpu->arch.root_mmu);
free_mmu_pages(&vcpu->arch.guest_mmu);
mmu_free_memory_caches(vcpu);
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index b0d4b31557b2..e3e3d29ba7bc 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -6,6 +6,8 @@
#include <linux/kvm_host.h>
#include <asm/kvm_host.h>
+#include "mmu.h"
+
#undef MMU_DEBUG
#ifdef MMU_DEBUG
@@ -204,6 +206,15 @@ static inline void kvm_mmu_free_private_spt(struct kvm_mmu_page *sp)
if (sp->private_spt)
free_page((unsigned long)sp->private_spt);
}
+
+static inline gfn_t kvm_gfn_for_root(struct kvm *kvm, struct kvm_mmu_page *root,
+ gfn_t gfn)
+{
+ if (is_private_sp(root))
+ return kvm_gfn_to_private(kvm, gfn);
+ else
+ return kvm_gfn_to_shared(kvm, gfn);
+}
#else
static inline void *kvm_mmu_private_spt(struct kvm_mmu_page *sp)
{
@@ -221,6 +232,12 @@ static inline void kvm_mmu_alloc_private_spt(struct kvm_vcpu *vcpu, struct kvm_m
static inline void kvm_mmu_free_private_spt(struct kvm_mmu_page *sp)
{
}
+
+static inline gfn_t kvm_gfn_for_root(struct kvm *kvm, struct kvm_mmu_page *root,
+ gfn_t gfn)
+{
+ return gfn;
+}
#endif
static inline bool kvm_mmu_page_ad_need_write_protect(struct kvm_mmu_page *sp)
@@ -374,12 +391,12 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
.max_level = vcpu->kvm->arch.tdp_max_page_level,
.req_level = PG_LEVEL_4K,
.goal_level = PG_LEVEL_4K,
- .is_private = kvm_mem_is_private(vcpu->kvm, cr2_or_gpa >> PAGE_SHIFT),
+ .is_private = kvm_is_private_gpa(vcpu->kvm, cr2_or_gpa),
};
int r;
if (vcpu->arch.mmu->root_role.direct) {
- fault.gfn = fault.addr >> PAGE_SHIFT;
+ fault.gfn = gpa_to_gfn(fault.addr) & ~kvm_gfn_shared_mask(vcpu->kvm);
fault.slot = kvm_vcpu_gfn_to_memslot(vcpu, fault.gfn);
}
diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h
index 9e56a5b1024c..eab62baf8549 100644
--- a/arch/x86/kvm/mmu/tdp_iter.h
+++ b/arch/x86/kvm/mmu/tdp_iter.h
@@ -71,7 +71,7 @@ struct tdp_iter {
tdp_ptep_t pt_path[PT64_ROOT_MAX_LEVEL];
/* A pointer to the current SPTE */
tdp_ptep_t sptep;
- /* The lowest GFN mapped by the current SPTE */
+ /* The lowest GFN (shared bits included) mapped by the current SPTE */
gfn_t gfn;
/* The level of the root page given to the iterator */
int root_level;
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 67bc6084b497..a3402b33fa5d 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -270,6 +270,9 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp(struct kvm_vcpu *vcpu,
sp->spt = kvm_mmu_memory_cache_alloc(&vcpu->arch.mmu_shadow_page_cache);
sp->role = role;
+ if (kvm_mmu_page_role_is_private(role))
+ kvm_mmu_alloc_private_spt(vcpu, sp);
+
return sp;
}
@@ -292,7 +295,8 @@ static void tdp_mmu_init_sp(struct kvm_mmu_page *sp, tdp_ptep_t sptep,
trace_kvm_mmu_get_page(sp, true);
}
-hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu)
+static struct kvm_mmu_page *kvm_tdp_mmu_get_vcpu_root(struct kvm_vcpu *vcpu,
+ bool private)
{
union kvm_mmu_page_role role = vcpu->arch.mmu->root_role;
struct kvm *kvm = vcpu->kvm;
@@ -304,6 +308,8 @@ hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu)
* Check for an existing root before allocating a new one. Note, the
* role check prevents consuming an invalid root.
*/
+ if (private)
+ kvm_mmu_page_role_set_private(&role);
for_each_tdp_mmu_root(kvm, root, kvm_mmu_role_as_id(role)) {
if (root->role.word == role.word &&
kvm_tdp_mmu_get_root(root))
@@ -320,11 +326,17 @@ hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu)
spin_unlock(&kvm->arch.tdp_mmu_pages_lock);
out:
- return __pa(root->spt);
+ return root;
+}
+
+hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu, bool private)
+{
+ return __pa(kvm_tdp_mmu_get_vcpu_root(vcpu, private)->spt);
}
static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
- u64 old_spte, u64 new_spte, int level,
+ u64 old_spte, u64 new_spte,
+ union kvm_mmu_page_role role,
bool shared);
static void handle_changed_spte_acc_track(u64 old_spte, u64 new_spte, int level)
@@ -351,6 +363,8 @@ static void handle_changed_spte_dirty_log(struct kvm *kvm, int as_id, gfn_t gfn,
if ((!is_writable_pte(old_spte) || pfn_changed) &&
is_writable_pte(new_spte)) {
+ /* For memory slot operations, use GFN without aliasing */
+ gfn = gfn & ~kvm_gfn_shared_mask(kvm);
slot = __gfn_to_memslot(__kvm_memslots(kvm, as_id), gfn);
mark_page_dirty_in_slot(kvm, slot, gfn);
}
@@ -491,12 +505,78 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
REMOVED_SPTE, level);
}
handle_changed_spte(kvm, kvm_mmu_page_as_id(sp), gfn,
- old_spte, REMOVED_SPTE, level, shared);
+ old_spte, REMOVED_SPTE, sp->role,
+ shared);
+ }
+
+ if (is_private_sp(sp) &&
+ WARN_ON(static_call(kvm_x86_free_private_spt)(kvm, sp->gfn, sp->role.level,
+ kvm_mmu_private_spt(sp)))) {
+ /*
+ * Failed to unlink Secure EPT page and there is nothing to do
+ * further. Intentionally leak the page to prevent the kernel
+ * from accessing the encrypted page.
+ */
+ kvm_mmu_init_private_spt(sp, NULL);
}
call_rcu(&sp->rcu_head, tdp_mmu_free_sp_rcu_callback);
}
+static void *get_private_spt(gfn_t gfn, u64 new_spte, int level)
+{
+ if (is_shadow_present_pte(new_spte) && !is_last_spte(new_spte, level)) {
+ struct kvm_mmu_page *sp = to_shadow_page(pfn_to_hpa(spte_to_pfn(new_spte)));
+ void *private_spt = kvm_mmu_private_spt(sp);
+
+ WARN_ON_ONCE(!private_spt);
+ WARN_ON_ONCE(sp->role.level + 1 != level);
+ WARN_ON_ONCE(sp->gfn != gfn);
+ return private_spt;
+ }
+
+ return NULL;
+}
+
+static void handle_removed_private_spte(struct kvm *kvm, gfn_t gfn,
+ u64 old_spte, u64 new_spte,
+ int level)
+{
+ bool was_present = is_shadow_present_pte(old_spte);
+ bool is_present = is_shadow_present_pte(new_spte);
+ bool was_leaf = was_present && is_last_spte(old_spte, level);
+ bool is_leaf = is_present && is_last_spte(new_spte, level);
+ kvm_pfn_t old_pfn = spte_to_pfn(old_spte);
+ kvm_pfn_t new_pfn = spte_to_pfn(new_spte);
+ int ret;
+
+ /* Ignore change of software only bits. e.g. host_writable */
+ if (was_leaf == is_leaf && was_present == is_present)
+ return;
+
+ /*
+ * Allow only leaf page to be zapped. Reclaim Non-leaf page tables at
+ * destroying VM.
+ */
+ WARN_ON_ONCE(is_present);
+ if (!was_leaf)
+ return;
+
+ /* non-present -> non-present doesn't make sense. */
+ KVM_BUG_ON(!was_present, kvm);
+ KVM_BUG_ON(new_pfn, kvm);
+
+ /* Zapping leaf spte is allowed only when write lock is held. */
+ lockdep_assert_held_write(&kvm->mmu_lock);
+ ret = static_call(kvm_x86_zap_private_spte)(kvm, gfn, level);
+ /* Because write lock is held, operation should success. */
+ if (KVM_BUG_ON(ret, kvm))
+ return;
+
+ ret = static_call(kvm_x86_remove_private_spte)(kvm, gfn, level, old_pfn);
+ KVM_BUG_ON(ret, kvm);
+}
+
/**
* __handle_changed_spte - handle bookkeeping associated with an SPTE change
* @kvm: kvm instance
@@ -504,7 +584,7 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
* @gfn: the base GFN that was mapped by the SPTE
* @old_spte: The value of the SPTE before the change
* @new_spte: The value of the SPTE after the change
- * @level: the level of the PT the SPTE is part of in the paging structure
+ * @role: the role of the PT the SPTE is part of in the paging structure
* @shared: This operation may not be running under the exclusive use of
* the MMU lock and the operation must synchronize with other
* threads that might be modifying SPTEs.
@@ -513,14 +593,18 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
* This function must be called for all TDP SPTE modifications.
*/
static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
- u64 old_spte, u64 new_spte, int level,
- bool shared)
+ u64 old_spte, u64 new_spte,
+ union kvm_mmu_page_role role, bool shared)
{
+ bool is_private = kvm_mmu_page_role_is_private(role);
+ int level = role.level;
bool was_present = is_shadow_present_pte(old_spte);
bool is_present = is_shadow_present_pte(new_spte);
bool was_leaf = was_present && is_last_spte(old_spte, level);
bool is_leaf = is_present && is_last_spte(new_spte, level);
- bool pfn_changed = spte_to_pfn(old_spte) != spte_to_pfn(new_spte);
+ kvm_pfn_t old_pfn = spte_to_pfn(old_spte);
+ kvm_pfn_t new_pfn = spte_to_pfn(new_spte);
+ bool pfn_changed = old_pfn != new_pfn;
WARN_ON(level > PT64_ROOT_MAX_LEVEL);
WARN_ON(level < PG_LEVEL_4K);
@@ -587,7 +671,7 @@ static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
if (was_leaf && is_dirty_spte(old_spte) &&
(!is_present || !is_dirty_spte(new_spte) || pfn_changed))
- kvm_set_pfn_dirty(spte_to_pfn(old_spte));
+ kvm_set_pfn_dirty(old_pfn);
/*
* Recursively handle child PTs if the change removed a subtree from
@@ -596,19 +680,88 @@ static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
* pages are kernel allocations and should never be migrated.
*/
if (was_present && !was_leaf &&
- (is_leaf || !is_present || WARN_ON_ONCE(pfn_changed)))
+ (is_leaf || !is_present || WARN_ON_ONCE(pfn_changed))) {
+ KVM_BUG_ON(is_private != is_private_sptep(spte_to_child_pt(old_spte, level)),
+ kvm);
handle_removed_pt(kvm, spte_to_child_pt(old_spte, level), shared);
+ }
+
+ /*
+ * Secure-EPT requires to remove Secure-EPT tables after removing
+ * children. hooks after after handling lower page table by above
+ * handle_remove_pt().
+ */
+ if (is_private && !is_present)
+ handle_removed_private_spte(kvm, gfn, old_spte, new_spte, role.level);
}
static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
- u64 old_spte, u64 new_spte, int level,
- bool shared)
+ u64 old_spte, u64 new_spte,
+ union kvm_mmu_page_role role,
+ bool shared)
{
- __handle_changed_spte(kvm, as_id, gfn, old_spte, new_spte, level,
- shared);
- handle_changed_spte_acc_track(old_spte, new_spte, level);
+ __handle_changed_spte(kvm, as_id, gfn, old_spte, new_spte, role, shared);
+
+ handle_changed_spte_acc_track(old_spte, new_spte, role.level);
handle_changed_spte_dirty_log(kvm, as_id, gfn, old_spte,
- new_spte, level);
+ new_spte, role.level);
+}
+
+static int __must_check __set_private_spte_present(struct kvm *kvm, tdp_ptep_t sptep,
+ gfn_t gfn, u64 old_spte,
+ u64 new_spte, int level)
+{
+ bool was_present = is_shadow_present_pte(old_spte);
+ bool is_present = is_shadow_present_pte(new_spte);
+ bool is_leaf = is_present && is_last_spte(new_spte, level);
+ kvm_pfn_t new_pfn = spte_to_pfn(new_spte);
+ int ret = 0;
+
+ lockdep_assert_held(&kvm->mmu_lock);
+ /* TDP MMU doesn't change present -> present */
+ KVM_BUG_ON(was_present, kvm);
+
+ /*
+ * Use different call to either set up middle level
+ * private page table, or leaf.
+ */
+ if (is_leaf)
+ ret = static_call(kvm_x86_set_private_spte)(kvm, gfn, level, new_pfn);
+ else {
+ void *private_spt = get_private_spt(gfn, new_spte, level);
+
+ KVM_BUG_ON(!private_spt, kvm);
+ ret = static_call(kvm_x86_link_private_spt)(kvm, gfn, level, private_spt);
+ }
+
+ return ret;
+}
+
+static int __must_check set_private_spte_present(struct kvm *kvm, tdp_ptep_t sptep,
+ gfn_t gfn, u64 old_spte,
+ u64 new_spte, int level)
+{
+ int ret;
+
+ /*
+ * For private page table, callbacks are needed to propagate SPTE
+ * change into the protected page table. In order to atomically update
+ * both the SPTE and the protected page tables with callbacks, utilize
+ * freezing SPTE.
+ * - Freeze the SPTE. Set entry to REMOVED_SPTE.
+ * - Trigger callbacks for protected page tables.
+ * - Unfreeze the SPTE. Set the entry to new_spte.
+ */
+ lockdep_assert_held(&kvm->mmu_lock);
+ if (!try_cmpxchg64(sptep, &old_spte, REMOVED_SPTE))
+ return -EBUSY;
+
+ ret = __set_private_spte_present(kvm, sptep, gfn, old_spte, new_spte, level);
+ if (ret)
+ __kvm_tdp_mmu_write_spte(sptep, old_spte);
+ else
+ __kvm_tdp_mmu_write_spte(sptep, new_spte);
+ return ret;
}
/*
@@ -633,6 +786,7 @@ static inline int __must_check tdp_mmu_set_spte_atomic(struct kvm *kvm,
u64 new_spte)
{
u64 *sptep = rcu_dereference(iter->sptep);
+ bool freezed = false;
/*
* The caller is responsible for ensuring the old SPTE is not a REMOVED
@@ -644,17 +798,33 @@ static inline int __must_check tdp_mmu_set_spte_atomic(struct kvm *kvm,
lockdep_assert_held_read(&kvm->mmu_lock);
- /*
- * Note, fast_pf_fix_direct_spte() can also modify TDP MMU SPTEs and
- * does not hold the mmu_lock.
- */
- if (!try_cmpxchg64(sptep, &iter->old_spte, new_spte))
- return -EBUSY;
+ if (is_private_sptep(iter->sptep) && !is_removed_spte(new_spte)) {
+ int ret;
+
+ if (is_shadow_present_pte(new_spte)) {
+ ret = set_private_spte_present(kvm, iter->sptep, iter->gfn,
+ iter->old_spte, new_spte, iter->level);
+ if (ret)
+ return ret;
+ } else {
+ if (!try_cmpxchg64(sptep, &iter->old_spte, REMOVED_SPTE))
+ return -EBUSY;
+ freezed = true;
+ }
+ } else {
+ /*
+ * Note, fast_pf_fix_direct_spte() can also modify TDP MMU SPTEs
+ * and does not hold the mmu_lock.
+ */
+ if (!try_cmpxchg64(sptep, &iter->old_spte, new_spte))
+ return -EBUSY;
+ }
__handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
- new_spte, iter->level, true);
+ new_spte, sptep_to_sp(sptep)->role, true);
handle_changed_spte_acc_track(iter->old_spte, new_spte, iter->level);
-
+ if (freezed)
+ __kvm_tdp_mmu_write_spte(sptep, new_spte);
return 0;
}
@@ -715,6 +885,8 @@ static u64 __tdp_mmu_set_spte(struct kvm *kvm, int as_id, tdp_ptep_t sptep,
u64 old_spte, u64 new_spte, gfn_t gfn, int level,
bool record_acc_track, bool record_dirty_log)
{
+ union kvm_mmu_page_role role;
+
lockdep_assert_held_write(&kvm->mmu_lock);
/*
@@ -727,8 +899,17 @@ static u64 __tdp_mmu_set_spte(struct kvm *kvm, int as_id, tdp_ptep_t sptep,
WARN_ON(is_removed_spte(old_spte) || is_removed_spte(new_spte));
old_spte = kvm_tdp_mmu_write_spte(sptep, old_spte, new_spte, level);
+ if (is_private_sptep(sptep) && !is_removed_spte(new_spte) &&
+ is_shadow_present_pte(new_spte)) {
+ lockdep_assert_held_write(&kvm->mmu_lock);
+ /* Because write spin lock is held, no race. It should success. */
+ KVM_BUG_ON(__set_private_spte_present(kvm, sptep, gfn, old_spte,
+ new_spte, level), kvm);
+ }
- __handle_changed_spte(kvm, as_id, gfn, old_spte, new_spte, level, false);
+ role = sptep_to_sp(sptep)->role;
+ role.level = level;
+ __handle_changed_spte(kvm, as_id, gfn, old_spte, new_spte, role, false);
if (record_acc_track)
handle_changed_spte_acc_track(old_spte, new_spte, level);
@@ -780,8 +961,11 @@ static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm,
continue; \
else
-#define tdp_mmu_for_each_pte(_iter, _mmu, _start, _end) \
- for_each_tdp_pte(_iter, to_shadow_page(_mmu->root.hpa), _start, _end)
+#define tdp_mmu_for_each_pte(_iter, _mmu, _private, _start, _end) \
+ for_each_tdp_pte(_iter, \
+ to_shadow_page((_private) ? _mmu->private_root_hpa : \
+ _mmu->root.hpa), \
+ _start, _end)
/*
* Yield if the MMU lock is contended or this thread needs to return control
@@ -944,6 +1128,14 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
if (!zap_private && is_private_sp(root))
return false;
+ /*
+ * start and end doesn't have GFN shared bit. This function zaps
+ * a region including alias. Adjust shared bit of [start, end) if the
+ * root is shared.
+ */
+ start = kvm_gfn_for_root(kvm, root, start);
+ end = kvm_gfn_for_root(kvm, root, end);
+
rcu_read_lock();
for_each_tdp_pte_min_level(iter, root, PG_LEVEL_4K, start, end) {
@@ -1074,10 +1266,19 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu,
if (unlikely(!fault->slot))
new_spte = make_mmio_spte(vcpu, iter->gfn, ACC_ALL);
- else
- wrprot = make_spte(vcpu, sp, fault->slot, ACC_ALL, iter->gfn,
- fault->pfn, iter->old_spte, fault->prefetch, true,
- fault->map_writable, &new_spte);
+ else {
+ unsigned long pte_access = ACC_ALL;
+
+ /* TDX shared GPAs are no executable, enforce this for the SDV. */
+ if (kvm_gfn_shared_mask(vcpu->kvm) && !fault->is_private)
+ pte_access &= ~ACC_EXEC_MASK;
+
+ wrprot = make_spte(vcpu, sp, fault->slot, pte_access,
+ gpa_to_gfn(fault->addr)/* include shared bit */,
+ fault->pfn, iter->old_spte,
+ fault->prefetch, true, fault->map_writable,
+ &new_spte);
+ }
if (new_spte == iter->old_spte)
ret = RET_PF_SPURIOUS;
@@ -1155,6 +1356,8 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
struct kvm *kvm = vcpu->kvm;
struct tdp_iter iter;
struct kvm_mmu_page *sp;
+ gfn_t raw_gfn;
+ bool is_private = fault->is_private;
int ret = RET_PF_RETRY;
kvm_mmu_hugepage_adjust(vcpu, fault);
@@ -1163,7 +1366,17 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
rcu_read_lock();
- tdp_mmu_for_each_pte(iter, mmu, fault->gfn, fault->gfn + 1) {
+ raw_gfn = gpa_to_gfn(fault->addr);
+
+ if (is_error_noslot_pfn(fault->pfn) ||
+ !kvm_pfn_to_refcounted_page(fault->pfn)) {
+ if (is_private) {
+ rcu_read_unlock();
+ return -EFAULT;
+ }
+ }
+
+ tdp_mmu_for_each_pte(iter, mmu, is_private, raw_gfn, raw_gfn + 1) {
int r;
if (fault->nx_huge_page_workaround_enabled)
@@ -1193,9 +1406,14 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
sp->nx_huge_page_disallowed = fault->huge_page_disallowed;
- if (is_shadow_present_pte(iter.old_spte))
+ if (is_shadow_present_pte(iter.old_spte)) {
+ /*
+ * TODO: large page support.
+ * Doesn't support large page for TDX now
+ */
+ KVM_BUG_ON(is_private_sptep(iter.sptep), vcpu->kvm);
r = tdp_mmu_split_huge_page(kvm, &iter, sp, true);
- else
+ } else
r = tdp_mmu_link_sp(kvm, &iter, sp, true);
/*
@@ -1432,6 +1650,8 @@ static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp, union kvm_mm
sp->role = role;
sp->spt = (void *)__get_free_page(gfp);
+ /* TODO: large page support for private GPA. */
+ WARN_ON_ONCE(kvm_mmu_page_role_is_private(role));
if (!sp->spt) {
kmem_cache_free(mmu_page_header_cache, sp);
return NULL;
@@ -1447,6 +1667,11 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(struct kvm *kvm,
union kvm_mmu_page_role role = tdp_iter_child_role(iter);
struct kvm_mmu_page *sp;
+ KVM_BUG_ON(kvm_mmu_page_role_is_private(role) !=
+ is_private_sptep(iter->sptep), kvm);
+ /* TODO: Large page isn't supported for private SPTE yet. */
+ KVM_BUG_ON(kvm_mmu_page_role_is_private(role), kvm);
+
/*
* Since we are allocating while under the MMU lock we have to be
* careful about GFP flags. Use GFP_NOWAIT to avoid blocking on direct
@@ -1875,7 +2100,7 @@ int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
*root_level = vcpu->arch.mmu->root_role.level;
- tdp_mmu_for_each_pte(iter, mmu, gfn, gfn + 1) {
+ tdp_mmu_for_each_pte(iter, mmu, false, gfn, gfn + 1) {
leaf = iter.level;
sptes[leaf] = iter.old_spte;
}
@@ -1902,7 +2127,10 @@ u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, u64 addr,
gfn_t gfn = addr >> PAGE_SHIFT;
tdp_ptep_t sptep = NULL;
- tdp_mmu_for_each_pte(iter, mmu, gfn, gfn + 1) {
+ /* fast page fault for private GPA isn't supported. */
+ WARN_ON_ONCE(kvm_is_private_gpa(vcpu->kvm, addr));
+
+ tdp_mmu_for_each_pte(iter, mmu, false, gfn, gfn + 1) {
*spte = iter.old_spte;
sptep = iter.sptep;
}
diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h
index b32cbdf2f675..3ae3c3b8642a 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.h
+++ b/arch/x86/kvm/mmu/tdp_mmu.h
@@ -10,7 +10,7 @@
int kvm_mmu_init_tdp_mmu(struct kvm *kvm);
void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm);
-hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu);
+hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu, bool private);
__must_check static inline bool kvm_tdp_mmu_get_root(struct kvm_mmu_page *root)
{
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d6db3f19ad74..42f01d0d6a49 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -206,6 +206,7 @@ struct page *kvm_pfn_to_refcounted_page(kvm_pfn_t pfn)
return NULL;
}
+EXPORT_SYMBOL_GPL(kvm_pfn_to_refcounted_page);
/*
* Switches to specified vcpu, until a matching vcpu_put()
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TDX EPT
violation.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index 7903473abad1..c4d67dd9ddf8 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -20,11 +20,11 @@ Patch Layer status
* TDX architectural definitions: Applied
* TD VM creation/destruction: Applied
* TD vcpu creation/destruction: Applied
-* TDX EPT violation: Not yet
+* TDX EPT violation: Applying
* TD finalization: Not yet
* TD vcpu enter/exit: Not yet
* TD vcpu interrupts/exit/hypercall: Not yet
* KVM MMU GPA shared bits: Applied
* KVM TDP refactoring for TDX: Applied
-* KVM TDP MMU hooks: Applying
+* KVM TDP MMU hooks: Applied
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX doesn't support dirty logging. Report dirty logging isn't supported so
that device model, for example qemu, can properly handle it. Silently
ignore on dirty logging on private GFNs of TDX.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/mmu.c | 3 +++
arch/x86/kvm/mmu/tdp_mmu.c | 36 +++++++++++++++++++++++++++++++++++-
arch/x86/kvm/x86.c | 8 ++++++++
include/linux/kvm_host.h | 1 +
virt/kvm/kvm_main.c | 10 +++++++++-
5 files changed, 56 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 3d68da838f94..1f250fa8ce36 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6706,6 +6706,9 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
for_each_rmap_spte(rmap_head, &iter, sptep) {
sp = sptep_to_sp(sptep);
+ /* Private page dirty logging is not supported yet. */
+ KVM_BUG_ON(is_private_sptep(sptep), kvm);
+
/*
* We cannot do huge page mapping for indirect shadow pages,
* which are found on the last rmap (level = 1) when not using
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index a3402b33fa5d..58a236a69ec7 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1474,9 +1474,27 @@ static __always_inline bool kvm_tdp_mmu_handle_gfn(struct kvm *kvm,
* into this helper allow blocking; it'd be dead, wasteful code.
*/
for_each_tdp_mmu_root(kvm, root, range->slot->as_id) {
+ gfn_t start;
+ gfn_t end;
+
+ /*
+ * For now, operation on private GPA, e.g. dirty page logging,
+ * isn't supported yet.
+ */
+ if (is_private_sp(root))
+ continue;
+
rcu_read_lock();
- tdp_root_for_each_leaf_pte(iter, root, range->start, range->end)
+ /*
+ * For TDX shared mapping, set GFN shared bit to the range,
+ * so the handler() doesn't need to set it, to avoid duplicated
+ * code in multiple handler()s.
+ */
+ start = kvm_gfn_to_shared(kvm, range->start);
+ end = kvm_gfn_to_shared(kvm, range->end);
+
+ tdp_root_for_each_leaf_pte(iter, root, start, end)
ret |= handler(kvm, &iter, range);
rcu_read_unlock();
@@ -1959,6 +1977,13 @@ void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
struct kvm_mmu_page *root;
lockdep_assert_held_write(&kvm->mmu_lock);
+ /*
+ * First TDX generation doesn't support clearing dirty bit,
+ * since there's no secure EPT API to support it. For now silently
+ * ignore KVM_CLEAR_DIRTY_LOG.
+ */
+ if (!kvm_arch_dirty_log_supported(kvm))
+ return;
for_each_tdp_mmu_root(kvm, root, slot->as_id)
clear_dirty_pt_masked(kvm, root, gfn, mask, wrprot);
}
@@ -2078,6 +2103,15 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm,
bool spte_set = false;
lockdep_assert_held_write(&kvm->mmu_lock);
+
+ /*
+ * First TDX generation doesn't support write protecting private
+ * mappings, silently ignore the request. KVM_GET_DIRTY_LOG etc
+ * can reach here, no warning.
+ */
+ if (!kvm_arch_dirty_log_supported(kvm))
+ return false;
+
for_each_tdp_mmu_root(kvm, root, slot->as_id)
spte_set |= write_protect_gfn(kvm, root, gfn, min_level);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a0960b468c74..6d7ca694e1c9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12589,6 +12589,9 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
u32 new_flags = new ? new->flags : 0;
bool log_dirty_pages = new_flags & KVM_MEM_LOG_DIRTY_PAGES;
+ if (!kvm_arch_dirty_log_supported(kvm) && log_dirty_pages)
+ return;
+
/*
* Update CPU dirty logging if dirty logging is being toggled. This
* applies to all operations.
@@ -13561,6 +13564,11 @@ int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
}
EXPORT_SYMBOL_GPL(kvm_sev_es_string_io);
+bool kvm_arch_dirty_log_supported(struct kvm *kvm)
+{
+ return kvm->arch.vm_type != KVM_X86_PROTECTED_VM;
+}
+
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 5a144497c930..3cd537f4b38b 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1495,6 +1495,7 @@ bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu);
int kvm_arch_post_init_vm(struct kvm *kvm);
void kvm_arch_pre_destroy_vm(struct kvm *kvm);
int kvm_arch_create_vm_debugfs(struct kvm *kvm);
+bool kvm_arch_dirty_log_supported(struct kvm *kvm);
#ifndef __KVM_HAVE_ARCH_VM_ALLOC
/*
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 42f01d0d6a49..e9f8225f3406 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1700,10 +1700,18 @@ static void kvm_replace_memslot(struct kvm *kvm,
}
}
+bool __weak kvm_arch_dirty_log_supported(struct kvm *kvm)
+{
+ return true;
+}
+
static int check_memory_region_flags(struct kvm *kvm,
const struct kvm_userspace_memory_region2 *mem)
{
- u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
+ u32 valid_flags = 0;
+
+ if (kvm_arch_dirty_log_supported(kvm))
+ valid_flags |= KVM_MEM_LOG_DIRTY_PAGES;
if (kvm_arch_has_private_mem(kvm))
valid_flags |= KVM_MEM_PRIVATE;
--
2.25.1
From: Isaku Yamahata <[email protected]>
To keep the case of non TDX intact, introduce a new config option for
private KVM MMU support. At the moment, this is synonym for
CONFIG_INTEL_TDX_HOST && CONFIG_KVM_INTEL. The config makes it clear
that the config is only for x86 KVM MMU.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/Kconfig | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 718010600956..45ac6b01af44 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -153,4 +153,8 @@ config KVM_XEN
config KVM_EXTERNAL_WRITE_TRACKING
bool
+config KVM_MMU_PRIVATE
+ def_bool y
+ depends on INTEL_TDX_HOST && KVM_INTEL
+
endif # VIRTUALIZATION
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX repurposes one GPA bit (51 bit or 47 bit based on configuration) to
indicate the GPA is private(if cleared) or shared (if set) with VMM. If
GPA.shared is set, GPA is covered by the existing conventional EPT pointed
by EPTP. If GPA.shared bit is cleared, GPA is covered by TDX module.
VMM has to issue SEAMCALLs to operate.
Add a member to remember GPA shared bit for each guest TDs, add address
conversion functions between private GPA and shared GPA and test if GPA
is private.
Because struct kvm_arch (or struct kvm which includes struct kvm_arch. See
kvm_arch_alloc_vm() that passes __GPF_ZERO) is zero-cleared when allocated,
the new member to remember GPA shared bit is guaranteed to be zero with
this patch unless it's initialized explicitly.
Co-developed-by: Rick Edgecombe <[email protected]>
Signed-off-by: Rick Edgecombe <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 4 ++++
arch/x86/kvm/mmu.h | 27 +++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.c | 5 +++++
3 files changed, 36 insertions(+)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 42fa696a04ea..1802ee8bf1ad 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1463,6 +1463,10 @@ struct kvm_arch {
*/
#define SPLIT_DESC_CACHE_MIN_NR_OBJECTS (SPTE_ENT_PER_PAGE + 1)
struct kvm_mmu_memory_cache split_desc_cache;
+
+#ifdef CONFIG_KVM_MMU_PRIVATE
+ gfn_t gfn_shared_mask;
+#endif
};
struct kvm_vm_stat {
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 168c46fd8dd1..34a7266f145f 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -278,4 +278,31 @@ static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu,
return gpa;
return translate_nested_gpa(vcpu, gpa, access, exception);
}
+
+static inline gfn_t kvm_gfn_shared_mask(const struct kvm *kvm)
+{
+#ifdef CONFIG_KVM_MMU_PRIVATE
+ return kvm->arch.gfn_shared_mask;
+#else
+ return 0;
+#endif
+}
+
+static inline gfn_t kvm_gfn_to_shared(const struct kvm *kvm, gfn_t gfn)
+{
+ return gfn | kvm_gfn_shared_mask(kvm);
+}
+
+static inline gfn_t kvm_gfn_to_private(const struct kvm *kvm, gfn_t gfn)
+{
+ return gfn & ~kvm_gfn_shared_mask(kvm);
+}
+
+static inline bool kvm_is_private_gpa(const struct kvm *kvm, gpa_t gpa)
+{
+ gfn_t mask = kvm_gfn_shared_mask(kvm);
+
+ return mask && !(gpa_to_gfn(gpa) & mask);
+}
+
#endif
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 1415ab60ce2c..1994f4463fd8 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -826,6 +826,11 @@ static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd)
kvm_tdx->attributes = td_params->attributes;
kvm_tdx->xfam = td_params->xfam;
+ if (td_params->exec_controls & TDX_EXEC_CONTROL_MAX_GPAW)
+ kvm->arch.gfn_shared_mask = gpa_to_gfn(BIT_ULL(51));
+ else
+ kvm->arch.gfn_shared_mask = gpa_to_gfn(BIT_ULL(47));
+
out:
/* kfree() accepts NULL. */
kfree(init_vm);
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of KVM TDP
refactoring for TDX.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index 8b8186e7bfeb..e893a3d714c7 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -25,6 +25,6 @@ Patch Layer status
* TD vcpu enter/exit: Not yet
* TD vcpu interrupts/exit/hypercall: Not yet
-* KVM MMU GPA shared bits: Applying
-* KVM TDP refactoring for TDX: Not yet
+* KVM MMU GPA shared bits: Applied
+* KVM TDP refactoring for TDX: Applying
* KVM TDP MMU hooks: Not yet
--
2.25.1
From: Yan Zhao <[email protected]>
TDX does not support write protection and hence page track.
Though !tdp_enabled and kvm_shadow_root_allocated(kvm) are always false
for TD guest, should also return false when external write tracking is
enabled.
Cc: Yuan Yao <[email protected]>
Signed-off-by: Yan Zhao <[email protected]>
---
arch/x86/kvm/mmu/page_track.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c
index 0a2ac438d647..d738d318ce17 100644
--- a/arch/x86/kvm/mmu/page_track.c
+++ b/arch/x86/kvm/mmu/page_track.c
@@ -22,6 +22,9 @@
bool kvm_page_track_write_tracking_enabled(struct kvm *kvm)
{
+ if (kvm->arch.vm_type == KVM_X86_PROTECTED_VM)
+ return false;
+
return IS_ENABLED(CONFIG_KVM_EXTERNAL_WRITE_TRACKING) ||
!tdp_enabled || kvm_shadow_root_allocated(kvm);
}
--
2.25.1
From: Sean Christopherson <[email protected]>
The difference of TDX EPT violation is how to retrieve information, GPA,
and exit qualification. To share the code to handle EPT violation, split
out the guts of EPT violation handler so that VMX/TDX exit handler can call
it after retrieving GPA and exit qualification.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
Reviewed-by: Kai Huang <[email protected]>
---
arch/x86/kvm/vmx/common.h | 33 +++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 25 +++----------------------
2 files changed, 36 insertions(+), 22 deletions(-)
create mode 100644 arch/x86/kvm/vmx/common.h
diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
new file mode 100644
index 000000000000..235908f3e044
--- /dev/null
+++ b/arch/x86/kvm/vmx/common.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __KVM_X86_VMX_COMMON_H
+#define __KVM_X86_VMX_COMMON_H
+
+#include <linux/kvm_host.h>
+
+#include "mmu.h"
+
+static inline int __vmx_handle_ept_violation(struct kvm_vcpu *vcpu, gpa_t gpa,
+ unsigned long exit_qualification)
+{
+ u64 error_code;
+
+ /* Is it a read fault? */
+ error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
+ ? PFERR_USER_MASK : 0;
+ /* Is it a write fault? */
+ error_code |= (exit_qualification & EPT_VIOLATION_ACC_WRITE)
+ ? PFERR_WRITE_MASK : 0;
+ /* Is it a fetch fault? */
+ error_code |= (exit_qualification & EPT_VIOLATION_ACC_INSTR)
+ ? PFERR_FETCH_MASK : 0;
+ /* ept page table entry is present? */
+ error_code |= (exit_qualification & EPT_VIOLATION_RWX_MASK)
+ ? PFERR_PRESENT_MASK : 0;
+
+ error_code |= (exit_qualification & EPT_VIOLATION_GVA_TRANSLATED) != 0 ?
+ PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;
+
+ return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
+}
+
+#endif /* __KVM_X86_VMX_COMMON_H */
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 9a713538c2ad..8f44b29d05e9 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -51,6 +51,7 @@
#include <asm/vmx.h>
#include "capabilities.h"
+#include "common.h"
#include "cpuid.h"
#include "hyperv.h"
#include "kvm_onhyperv.h"
@@ -5776,11 +5777,8 @@ static int handle_task_switch(struct kvm_vcpu *vcpu)
static int handle_ept_violation(struct kvm_vcpu *vcpu)
{
- unsigned long exit_qualification;
+ unsigned long exit_qualification = vmx_get_exit_qual(vcpu);
gpa_t gpa;
- u64 error_code;
-
- exit_qualification = vmx_get_exit_qual(vcpu);
/*
* EPT violation happened while executing iret from NMI,
@@ -5795,23 +5793,6 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
trace_kvm_page_fault(vcpu, gpa, exit_qualification);
-
- /* Is it a read fault? */
- error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
- ? PFERR_USER_MASK : 0;
- /* Is it a write fault? */
- error_code |= (exit_qualification & EPT_VIOLATION_ACC_WRITE)
- ? PFERR_WRITE_MASK : 0;
- /* Is it a fetch fault? */
- error_code |= (exit_qualification & EPT_VIOLATION_ACC_INSTR)
- ? PFERR_FETCH_MASK : 0;
- /* ept page table entry is present? */
- error_code |= (exit_qualification & EPT_VIOLATION_RWX_MASK)
- ? PFERR_PRESENT_MASK : 0;
-
- error_code |= (exit_qualification & EPT_VIOLATION_GVA_TRANSLATED) != 0 ?
- PFERR_GUEST_FINAL_MASK : PFERR_GUEST_PAGE_MASK;
-
vcpu->arch.exit_qualification = exit_qualification;
/*
@@ -5825,7 +5806,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
if (unlikely(allow_smaller_maxphyaddr && kvm_vcpu_is_illegal_gpa(vcpu, gpa)))
return kvm_emulate_instruction(vcpu, 0);
- return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
+ return __vmx_handle_ept_violation(vcpu, gpa, exit_qualification);
}
static int handle_ept_misconfig(struct kvm_vcpu *vcpu)
--
2.25.1
From: Sean Christopherson <[email protected]>
Add support to MMU caches for initializing a page with a custom 64-bit
value, e.g. to pre-fill an entire page table with non-zero PTE values.
The functionality will be used by x86 to support Intel's TDX, which needs
to set bit 63 in all non-present PTEs in order to prevent !PRESENT page
faults from getting reflected into the guest (Intel's EPT Violation #VE
architecture made the less than brilliant decision of having the per-PTE
behavior be opt-out instead of opt-in).
Signed-off-by: Sean Christopherson <[email protected]>
---
include/linux/kvm_types.h | 1 +
virt/kvm/kvm_main.c | 16 ++++++++++++++--
2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h
index 2728d49bbdf6..7c2b9332b7c5 100644
--- a/include/linux/kvm_types.h
+++ b/include/linux/kvm_types.h
@@ -94,6 +94,7 @@ struct kvm_mmu_memory_cache {
int nobjs;
gfp_t gfp_zero;
gfp_t gfp_custom;
+ u64 init_value;
struct kmem_cache *kmem_cache;
int capacity;
void **objects;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f8495e27d210..87400796df6e 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -381,12 +381,17 @@ static void kvm_flush_shadow_all(struct kvm *kvm)
static inline void *mmu_memory_cache_alloc_obj(struct kvm_mmu_memory_cache *mc,
gfp_t gfp_flags)
{
+ void *page;
+
gfp_flags |= mc->gfp_zero;
if (mc->kmem_cache)
return kmem_cache_alloc(mc->kmem_cache, gfp_flags);
- else
- return (void *)__get_free_page(gfp_flags);
+
+ page = (void *)__get_free_page(gfp_flags);
+ if (page && mc->init_value)
+ memset64(page, mc->init_value, PAGE_SIZE / sizeof(mc->init_value));
+ return page;
}
int __kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int capacity, int min)
@@ -401,6 +406,13 @@ int __kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int capacity,
if (WARN_ON_ONCE(!capacity))
return -EIO;
+ /*
+ * Custom init values can be used only for page allocations,
+ * and obviously conflict with __GFP_ZERO.
+ */
+ if (WARN_ON_ONCE(mc->init_value && (mc->kmem_cache || mc->gfp_zero)))
+ return -EIO;
+
mc->objects = kvmalloc_array(sizeof(void *), capacity, gfp);
if (!mc->objects)
return -ENOMEM;
--
2.25.1
From: Sean Christopherson <[email protected]>
EPT MMU masks are used commonly for VMX and TDX. The value needs to be
initialized in common code before both VMX/TDX-specific initialization
code.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 9 +++++++++
arch/x86/kvm/vmx/vmx.c | 4 ----
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 57240d6ab97a..58cbdc5aa2a2 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -4,6 +4,7 @@
#include "x86_ops.h"
#include "vmx.h"
#include "nested.h"
+#include "mmu.h"
#include "pmu.h"
#include "tdx.h"
#include "tdx_arch.h"
@@ -49,6 +50,14 @@ static __init int vt_hardware_setup(void)
if (ret)
return ret;
+ /*
+ * As kvm_mmu_set_ept_masks() updates enable_mmio_caching, call it
+ * before checking enable_mmio_caching.
+ */
+ if (enable_ept)
+ kvm_mmu_set_ept_masks(enable_ept_ad_bits,
+ cpu_has_vmx_ept_execute_only());
+
enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
return 0;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 8f44b29d05e9..23321b2208ae 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8370,10 +8370,6 @@ __init int vmx_hardware_setup(void)
set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
- if (enable_ept)
- kvm_mmu_set_ept_masks(enable_ept_ad_bits,
- cpu_has_vmx_ept_execute_only());
-
/*
* Setup shadow_me_value/shadow_me_mask to include MKTME KeyID
* bits to shadow_zero_check.
--
2.25.1
From: Sean Christopherson <[email protected]>
TDX defines SEAMCALL APIs to access TDX control structures corresponding to
the VMX VMCS. Introduce helper accessors to hide its SEAMCALL ABI details.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.h | 95 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 95 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 5fa4d3198873..7c8f5880d104 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -57,6 +57,101 @@ static inline struct vcpu_tdx *to_tdx(struct kvm_vcpu *vcpu)
return container_of(vcpu, struct vcpu_tdx, vcpu);
}
+static __always_inline void tdvps_vmcs_check(u32 field, u8 bits)
+{
+#define VMCS_ENC_ACCESS_TYPE_MASK 0x1UL
+#define VMCS_ENC_ACCESS_TYPE_FULL 0x0UL
+#define VMCS_ENC_ACCESS_TYPE_HIGH 0x1UL
+#define VMCS_ENC_ACCESS_TYPE(field) ((field) & VMCS_ENC_ACCESS_TYPE_MASK)
+
+ /* TDX is 64bit only. HIGH field isn't supported. */
+ BUILD_BUG_ON_MSG(__builtin_constant_p(field) &&
+ VMCS_ENC_ACCESS_TYPE(field) == VMCS_ENC_ACCESS_TYPE_HIGH,
+ "Read/Write to TD VMCS *_HIGH fields not supported");
+
+ BUILD_BUG_ON(bits != 16 && bits != 32 && bits != 64);
+
+#define VMCS_ENC_WIDTH_MASK GENMASK(14, 13)
+#define VMCS_ENC_WIDTH_16BIT (0UL << 13)
+#define VMCS_ENC_WIDTH_64BIT (1UL << 13)
+#define VMCS_ENC_WIDTH_32BIT (2UL << 13)
+#define VMCS_ENC_WIDTH_NATURAL (3UL << 13)
+#define VMCS_ENC_WIDTH(field) ((field) & VMCS_ENC_WIDTH_MASK)
+
+ /* TDX is 64bit only. i.e. natural width = 64bit. */
+ BUILD_BUG_ON_MSG(bits != 64 && __builtin_constant_p(field) &&
+ (VMCS_ENC_WIDTH(field) == VMCS_ENC_WIDTH_64BIT ||
+ VMCS_ENC_WIDTH(field) == VMCS_ENC_WIDTH_NATURAL),
+ "Invalid TD VMCS access for 64-bit field");
+ BUILD_BUG_ON_MSG(bits != 32 && __builtin_constant_p(field) &&
+ VMCS_ENC_WIDTH(field) == VMCS_ENC_WIDTH_32BIT,
+ "Invalid TD VMCS access for 32-bit field");
+ BUILD_BUG_ON_MSG(bits != 16 && __builtin_constant_p(field) &&
+ VMCS_ENC_WIDTH(field) == VMCS_ENC_WIDTH_16BIT,
+ "Invalid TD VMCS access for 16-bit field");
+}
+
+static __always_inline void tdvps_state_non_arch_check(u64 field, u8 bits) {}
+static __always_inline void tdvps_management_check(u64 field, u8 bits) {}
+
+#define TDX_BUILD_TDVPS_ACCESSORS(bits, uclass, lclass) \
+static __always_inline u##bits td_##lclass##_read##bits(struct vcpu_tdx *tdx, \
+ u32 field) \
+{ \
+ struct tdx_module_output out; \
+ u64 err; \
+ \
+ tdvps_##lclass##_check(field, bits); \
+ err = tdh_vp_rd(tdx->tdvpr_pa, TDVPS_##uclass(field), &out); \
+ if (KVM_BUG_ON(err, tdx->vcpu.kvm)) { \
+ pr_err("TDH_VP_RD["#uclass".0x%x] failed: 0x%llx\n", \
+ field, err); \
+ return 0; \
+ } \
+ return (u##bits)out.r8; \
+} \
+static __always_inline void td_##lclass##_write##bits(struct vcpu_tdx *tdx, \
+ u32 field, u##bits val) \
+{ \
+ struct tdx_module_output out; \
+ u64 err; \
+ \
+ tdvps_##lclass##_check(field, bits); \
+ err = tdh_vp_wr(tdx->tdvpr_pa, TDVPS_##uclass(field), val, \
+ GENMASK_ULL(bits - 1, 0), &out); \
+ if (KVM_BUG_ON(err, tdx->vcpu.kvm)) \
+ pr_err("TDH_VP_WR["#uclass".0x%x] = 0x%llx failed: 0x%llx\n", \
+ field, (u64)val, err); \
+} \
+static __always_inline void td_##lclass##_setbit##bits(struct vcpu_tdx *tdx, \
+ u32 field, u64 bit) \
+{ \
+ struct tdx_module_output out; \
+ u64 err; \
+ \
+ tdvps_##lclass##_check(field, bits); \
+ err = tdh_vp_wr(tdx->tdvpr_pa, TDVPS_##uclass(field), bit, bit, &out); \
+ if (KVM_BUG_ON(err, tdx->vcpu.kvm)) \
+ pr_err("TDH_VP_WR["#uclass".0x%x] |= 0x%llx failed: 0x%llx\n", \
+ field, bit, err); \
+} \
+static __always_inline void td_##lclass##_clearbit##bits(struct vcpu_tdx *tdx, \
+ u32 field, u64 bit) \
+{ \
+ struct tdx_module_output out; \
+ u64 err; \
+ \
+ tdvps_##lclass##_check(field, bits); \
+ err = tdh_vp_wr(tdx->tdvpr_pa, TDVPS_##uclass(field), 0, bit, &out); \
+ if (KVM_BUG_ON(err, tdx->vcpu.kvm)) \
+ pr_err("TDH_VP_WR["#uclass".0x%x] &= ~0x%llx failed: 0x%llx\n", \
+ field, bit, err); \
+}
+
+TDX_BUILD_TDVPS_ACCESSORS(16, VMCS, vmcs);
+TDX_BUILD_TDVPS_ACCESSORS(32, VMCS, vmcs);
+TDX_BUILD_TDVPS_ACCESSORS(64, VMCS, vmcs);
+
static __always_inline u64 td_tdcs_exec_read64(struct kvm_tdx *kvm_tdx, u32 field)
{
struct tdx_module_output out;
--
2.25.1
From: Sean Christopherson <[email protected]>
For virtual IO, the guest TD shares guest pages with VMM without
encryption. Shared EPT is used to map guest pages in unprotected way.
Add the VMCS field encoding for the shared EPTP, which will be used by
TDX to have separate EPT walks for private GPAs (existing EPTP) versus
shared GPAs (new shared EPTP).
Set shared EPT pointer value for the TDX guest to initialize TDX MMU.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/include/asm/vmx.h | 1 +
arch/x86/kvm/vmx/main.c | 13 ++++++++++++-
arch/x86/kvm/vmx/tdx.c | 5 +++++
arch/x86/kvm/vmx/x86_ops.h | 4 ++++
4 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 752d53652007..1205018b5b6b 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -234,6 +234,7 @@ enum vmcs_field {
TSC_MULTIPLIER_HIGH = 0x00002033,
TERTIARY_VM_EXEC_CONTROL = 0x00002034,
TERTIARY_VM_EXEC_CONTROL_HIGH = 0x00002035,
+ SHARED_EPT_POINTER = 0x0000203C,
PID_POINTER_TABLE = 0x00002042,
PID_POINTER_TABLE_HIGH = 0x00002043,
GUEST_PHYSICAL_ADDRESS = 0x00002400,
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 58cbdc5aa2a2..60fc4dfb22fd 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -142,6 +142,17 @@ static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vmx_vcpu_reset(vcpu, init_event);
}
+static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
+ int pgd_level)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
+ return;
+ }
+
+ vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -275,7 +286,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.write_tsc_offset = vmx_write_tsc_offset,
.write_tsc_multiplier = vmx_write_tsc_multiplier,
- .load_mmu_pgd = vmx_load_mmu_pgd,
+ .load_mmu_pgd = vt_load_mmu_pgd,
.check_intercept = vmx_check_intercept,
.handle_exit_irqoff = vmx_handle_exit_irqoff,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 1994f4463fd8..340034db15a7 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -404,6 +404,11 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
*/
}
+void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
+{
+ td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 92af5d2d5db7..89d18369b117 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -157,6 +157,8 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
+
+void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline void tdx_hardware_unsetup(void) {}
@@ -178,6 +180,8 @@ static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
+
+static inline void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level) {}
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
From: Yuan Yao <[email protected]>
TDX module internally uses locks to protect internal resources. It tries
to acquire the locks. If it fails to obtain the lock, it returns
TDX_OPERAND_BUSY error without spin because its execution time limitation.
TDX SEAMCALL API reference describes what resources are used. It's known
which TDX SEAMCALL can cause contention with which resources. VMM can
avoid contention inside the TDX module by avoiding contentious TDX SEAMCALL
with, for example, spinlock. Because OS knows better its process
scheduling and its scalability, a lock at OS/VMM layer would work better
than simply retrying TDX SEAMCALLs.
TDH.MEM.* API except for TDH.MEM.TRACK operates on a secure EPT tree and
the TDX module internally tries to acquire the lock of the secure EPT tree.
They return TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT in case of failure to
get the lock. TDX KVM allows sept callbacks to return error so that TDP
MMU layer can retry.
TDH.VP.ENTER is an exception with zero-step attack mitigation. Normally
TDH.VP.ENTER uses only TD vcpu resources and it doesn't cause contention.
When a zero-step attack is suspected, it obtains a secure EPT tree lock and
tracks the GPAs causing a secure EPT fault. Thus TDG.VP.ENTER may result
in TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT. Also TDH.MEM.* SEAMCALLs may
result in TDX_OPERAN_BUSY | TDX_OPERAND_ID_SEPT.
Retry TDX TDH.MEM.* API and TDH.VP.ENTER on the error because the error is
a rare event caused by zero-step attack mitigation and spinlock can not be
used for TDH.VP.ENTER due to indefinite time execution.
Signed-off-by: Yuan Yao <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx_ops.h | 42 ++++++++++++++++++++++++++++++++------
1 file changed, 36 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h
index 177f444ebbb3..b03d95848e3e 100644
--- a/arch/x86/kvm/vmx/tdx_ops.h
+++ b/arch/x86/kvm/vmx/tdx_ops.h
@@ -38,6 +38,36 @@ static inline u64 kvm_seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
void pr_tdx_error(u64 op, u64 error_code, const struct tdx_module_output *out);
#endif
+/*
+ * TDX module acquires its internal lock for resources. It doesn't spin to get
+ * locks because of its restrictions of allowed execution time. Instead, it
+ * returns TDX_OPERAND_BUSY with an operand id.
+ *
+ * Multiple VCPUs can operate on SEPT. Also with zero-step attack mitigation,
+ * TDH.VP.ENTER may rarely acquire SEPT lock and release it when zero-step
+ * attack is suspected. It results in TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT
+ * with TDH.MEM.* operation. Note: TDH.MEM.TRACK is an exception.
+ *
+ * Because TDP MMU uses read lock for scalability, spin lock around SEAMCALL
+ * spoils TDP MMU effort. Retry several times with the assumption that SEPT
+ * lock contention is rare. But don't loop forever to avoid lockup. Let TDP
+ * MMU retry.
+ */
+#define TDX_ERROR_SEPT_BUSY (TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT)
+
+static inline u64 kvm_seamcall_sept(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
+ struct tdx_module_output *out)
+{
+#define SEAMCALL_RETRY_MAX 16
+ int retry = SEAMCALL_RETRY_MAX;
+ u64 ret;
+
+ do {
+ ret = kvm_seamcall(op, rcx, rdx, r8, r9, out);
+ } while (ret == TDX_ERROR_SEPT_BUSY && retry-- > 0);
+ return ret;
+}
+
static inline u64 tdh_mng_addcx(hpa_t tdr, hpa_t addr)
{
clflush_cache_range(__va(addr), PAGE_SIZE);
@@ -48,14 +78,14 @@ static inline u64 tdh_mem_page_add(hpa_t tdr, gpa_t gpa, hpa_t hpa, hpa_t source
struct tdx_module_output *out)
{
clflush_cache_range(__va(hpa), PAGE_SIZE);
- return kvm_seamcall(TDH_MEM_PAGE_ADD, gpa, tdr, hpa, source, out);
+ return kvm_seamcall_sept(TDH_MEM_PAGE_ADD, gpa, tdr, hpa, source, out);
}
static inline u64 tdh_mem_sept_add(hpa_t tdr, gpa_t gpa, int level, hpa_t page,
struct tdx_module_output *out)
{
clflush_cache_range(__va(page), PAGE_SIZE);
- return kvm_seamcall(TDH_MEM_SEPT_ADD, gpa | level, tdr, page, 0, out);
+ return kvm_seamcall_sept(TDH_MEM_SEPT_ADD, gpa | level, tdr, page, 0, out);
}
static inline u64 tdh_mem_sept_remove(hpa_t tdr, gpa_t gpa, int level,
@@ -81,13 +111,13 @@ static inline u64 tdh_mem_page_aug(hpa_t tdr, gpa_t gpa, hpa_t hpa,
struct tdx_module_output *out)
{
clflush_cache_range(__va(hpa), PAGE_SIZE);
- return kvm_seamcall(TDH_MEM_PAGE_AUG, gpa, tdr, hpa, 0, out);
+ return kvm_seamcall_sept(TDH_MEM_PAGE_AUG, gpa, tdr, hpa, 0, out);
}
static inline u64 tdh_mem_range_block(hpa_t tdr, gpa_t gpa, int level,
struct tdx_module_output *out)
{
- return kvm_seamcall(TDH_MEM_RANGE_BLOCK, gpa | level, tdr, 0, 0, out);
+ return kvm_seamcall_sept(TDH_MEM_RANGE_BLOCK, gpa | level, tdr, 0, 0, out);
}
static inline u64 tdh_mng_key_config(hpa_t tdr)
@@ -169,7 +199,7 @@ static inline u64 tdh_phymem_page_reclaim(hpa_t page,
static inline u64 tdh_mem_page_remove(hpa_t tdr, gpa_t gpa, int level,
struct tdx_module_output *out)
{
- return kvm_seamcall(TDH_MEM_PAGE_REMOVE, gpa | level, tdr, 0, 0, out);
+ return kvm_seamcall_sept(TDH_MEM_PAGE_REMOVE, gpa | level, tdr, 0, 0, out);
}
static inline u64 tdh_sys_lp_shutdown(void)
@@ -185,7 +215,7 @@ static inline u64 tdh_mem_track(hpa_t tdr)
static inline u64 tdh_mem_range_unblock(hpa_t tdr, gpa_t gpa, int level,
struct tdx_module_output *out)
{
- return kvm_seamcall(TDH_MEM_RANGE_UNBLOCK, gpa | level, tdr, 0, 0, out);
+ return kvm_seamcall_sept(TDH_MEM_RANGE_UNBLOCK, gpa | level, tdr, 0, 0, out);
}
static inline u64 tdh_phymem_cache_wb(bool resume)
--
2.25.1
From: Isaku Yamahata <[email protected]>
The TDX support will need the "suppress #VE" bit (bit 63) set as the
initial value for SPTE. To reduce code change size, introduce a new macro
SHADOW_NONPRESENT_VALUE for the initial value for the shadow page table
entry (SPTE) and replace hard-coded value 0 for it. Initialize shadow page
tables with their value.
The plan is to unconditionally set the "suppress #VE" bit for both AMD and
Intel as: 1) AMD hardware uses the bit 63 as NX for present SPTE and
ignored for non-present SPTE; 2) for conventional VMX guests, KVM never
enables the "EPT-violation #VE" in VMCS control and "suppress #VE" bit is
ignored by hardware.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/mmu.c | 17 +++++++++++++----
arch/x86/kvm/mmu/paging_tmpl.h | 3 ++-
arch/x86/kvm/mmu/spte.h | 2 ++
arch/x86/kvm/mmu/tdp_mmu.c | 15 ++++++++-------
4 files changed, 25 insertions(+), 12 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a11183dbaaa0..6026c5c130d4 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -559,9 +559,9 @@ static u64 mmu_spte_clear_track_bits(struct kvm *kvm, u64 *sptep)
if (!is_shadow_present_pte(old_spte) ||
!spte_has_volatile_bits(old_spte))
- __update_clear_spte_fast(sptep, 0ull);
+ __update_clear_spte_fast(sptep, SHADOW_NONPRESENT_VALUE);
else
- old_spte = __update_clear_spte_slow(sptep, 0ull);
+ old_spte = __update_clear_spte_slow(sptep, SHADOW_NONPRESENT_VALUE);
if (!is_shadow_present_pte(old_spte))
return old_spte;
@@ -595,7 +595,7 @@ static u64 mmu_spte_clear_track_bits(struct kvm *kvm, u64 *sptep)
*/
static void mmu_spte_clear_no_track(u64 *sptep)
{
- __update_clear_spte_fast(sptep, 0ull);
+ __update_clear_spte_fast(sptep, SHADOW_NONPRESENT_VALUE);
}
static u64 mmu_spte_get_lockless(u64 *sptep)
@@ -6013,7 +6013,16 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu)
vcpu->arch.mmu_page_header_cache.kmem_cache = mmu_page_header_cache;
vcpu->arch.mmu_page_header_cache.gfp_zero = __GFP_ZERO;
- vcpu->arch.mmu_shadow_page_cache.gfp_zero = __GFP_ZERO;
+ /*
+ * When X86_64, initial SEPT entries are initialized with
+ * SHADOW_NONPRESENT_VALUE. Otherwise zeroed. See
+ * mmu_memory_cache_alloc_obj().
+ */
+ if (IS_ENABLED(CONFIG_X86_64))
+ vcpu->arch.mmu_shadow_page_cache.init_value =
+ SHADOW_NONPRESENT_VALUE;
+ if (!vcpu->arch.mmu_shadow_page_cache.init_value)
+ vcpu->arch.mmu_shadow_page_cache.gfp_zero = __GFP_ZERO;
vcpu->arch.mmu = &vcpu->arch.root_mmu;
vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 57f0b75c80f9..f5b0e7c3877e 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -1025,7 +1025,8 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
gpa_t pte_gpa;
gfn_t gfn;
- if (!sp->spt[i])
+ /* spt[i] has initial value of shadow page table allocation */
+ if (sp->spt[i] == SHADOW_NONPRESENT_VALUE)
continue;
pte_gpa = first_pte_gpa + i * sizeof(pt_element_t);
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index 1279db2eab44..a99eb7d4ae5d 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -148,6 +148,8 @@ static_assert(MMIO_SPTE_GEN_LOW_BITS == 8 && MMIO_SPTE_GEN_HIGH_BITS == 11);
#define MMIO_SPTE_GEN_MASK GENMASK_ULL(MMIO_SPTE_GEN_LOW_BITS + MMIO_SPTE_GEN_HIGH_BITS - 1, 0)
+#define SHADOW_NONPRESENT_VALUE 0ULL
+
extern u64 __read_mostly shadow_host_writable_mask;
extern u64 __read_mostly shadow_mmu_writable_mask;
extern u64 __read_mostly shadow_nx_mask;
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index f2b56584089b..76e3751c8e9d 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -689,7 +689,7 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
* here since the SPTE is going from non-present to non-present. Use
* the raw write helper to avoid an unnecessary check on volatile bits.
*/
- __kvm_tdp_mmu_write_spte(iter->sptep, 0);
+ __kvm_tdp_mmu_write_spte(iter->sptep, SHADOW_NONPRESENT_VALUE);
return 0;
}
@@ -866,8 +866,8 @@ static void __tdp_mmu_zap_root(struct kvm *kvm, struct kvm_mmu_page *root,
continue;
if (!shared)
- tdp_mmu_set_spte(kvm, &iter, 0);
- else if (tdp_mmu_set_spte_atomic(kvm, &iter, 0))
+ tdp_mmu_set_spte(kvm, &iter, SHADOW_NONPRESENT_VALUE);
+ else if (tdp_mmu_set_spte_atomic(kvm, &iter, SHADOW_NONPRESENT_VALUE))
goto retry;
}
}
@@ -923,8 +923,9 @@ bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
if (WARN_ON_ONCE(!is_shadow_present_pte(old_spte)))
return false;
- __tdp_mmu_set_spte(kvm, kvm_mmu_page_as_id(sp), sp->ptep, old_spte, 0,
- sp->gfn, sp->role.level + 1, true, true);
+ __tdp_mmu_set_spte(kvm, kvm_mmu_page_as_id(sp), sp->ptep, old_spte,
+ SHADOW_NONPRESENT_VALUE, sp->gfn, sp->role.level + 1,
+ true, true);
return true;
}
@@ -958,7 +959,7 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
!is_last_spte(iter.old_spte, iter.level))
continue;
- tdp_mmu_set_spte(kvm, &iter, 0);
+ tdp_mmu_set_spte(kvm, &iter, SHADOW_NONPRESENT_VALUE);
flush = true;
}
@@ -1326,7 +1327,7 @@ static bool set_spte_gfn(struct kvm *kvm, struct tdp_iter *iter,
* invariant that the PFN of a present * leaf SPTE can never change.
* See __handle_changed_spte().
*/
- tdp_mmu_set_spte(kvm, iter, 0);
+ tdp_mmu_set_spte(kvm, iter, SHADOW_NONPRESENT_VALUE);
if (!pte_write(range->pte)) {
new_spte = kvm_mmu_changed_pte_notifier_make_spte(iter->old_spte,
--
2.25.1
From: Sean Christopherson <[email protected]>
For TD guest, the current way to emulate MMIO doesn't work any more, as KVM
is not able to access the private memory of TD guest and do the emulation.
Instead, TD guest expects to receive #VE when it accesses the MMIO and then
it can explicitly make hypercall to KVM to get the expected information.
To achieve this, the TDX module always enables "EPT-violation #VE" in the
VMCS control. And accordingly, for the MMIO spte for the shared GPA,
1. KVM needs to set "suppress #VE" bit for the non-present SPTE so that EPT
violation happens on TD accessing MMIO range. 2. On EPT violation, KVM
sets the MMIO spte to clear "suppress #VE" bit so the TD guest can receive
the #VE instead of EPT misconfigration unlike VMX case. For the shared GPA
that is not populated yet, EPT violation need to be triggered when TD guest
accesses such shared GPA. The non-present SPTE value for shared GPA should
set "suppress #VE" bit.
Add "suppress #VE" bit (bit 63) to SHADOW_NONPRESENT_VALUE and
REMOVED_SPTE. Unconditionally set the "suppress #VE" bit (which is bit 63)
for both AMD and Intel as: 1) AMD hardware doesn't use this bit when
present bit is off; 2) for normal VMX guest, KVM never enables the
"EPT-violation #VE" in VMCS control and "suppress #VE" bit is ignored by
hardware.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/spte.h | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index a99eb7d4ae5d..a57667810344 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -148,7 +148,20 @@ static_assert(MMIO_SPTE_GEN_LOW_BITS == 8 && MMIO_SPTE_GEN_HIGH_BITS == 11);
#define MMIO_SPTE_GEN_MASK GENMASK_ULL(MMIO_SPTE_GEN_LOW_BITS + MMIO_SPTE_GEN_HIGH_BITS - 1, 0)
+/*
+ * Non-present SPTE value for both VMX and SVM for TDP MMU.
+ * For SVM NPT, for non-present spte (bit 0 = 0), other bits are ignored.
+ * For VMX EPT, bit 63 is ignored if #VE is disabled. (EPT_VIOLATION_VE=0)
+ * bit 63 is #VE suppress if #VE is enabled. (EPT_VIOLATION_VE=1)
+ * For TDX:
+ * TDX module sets EPT_VIOLATION_VE for Secure-EPT and conventional EPT
+ */
+#ifdef CONFIG_X86_64
+#define SHADOW_NONPRESENT_VALUE BIT_ULL(63)
+static_assert(!(SHADOW_NONPRESENT_VALUE & SPTE_MMU_PRESENT_MASK));
+#else
#define SHADOW_NONPRESENT_VALUE 0ULL
+#endif
extern u64 __read_mostly shadow_host_writable_mask;
extern u64 __read_mostly shadow_mmu_writable_mask;
@@ -195,7 +208,7 @@ extern u64 __read_mostly shadow_nonpresent_or_rsvd_mask;
*
* Only used by the TDP MMU.
*/
-#define REMOVED_SPTE 0x5a0ULL
+#define REMOVED_SPTE (SHADOW_NONPRESENT_VALUE | 0x5a0ULL)
/* Removed SPTEs must not be misconstrued as shadow present PTEs. */
static_assert(!(REMOVED_SPTE & SPTE_MMU_PRESENT_MASK));
--
2.25.1
From: Isaku Yamahata <[email protected]>
As TDP MMU is becoming main stream than the legacy MMU, the legacy MMU
support for TDX isn't implemented. TDX requires KVM mmio caching. Disable
TDX support when TDP MMU or mmio caching aren't supported.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/mmu.c | 1 +
arch/x86/kvm/vmx/main.c | 12 ++++++++++++
2 files changed, 13 insertions(+)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 1f250fa8ce36..6074aa09cd87 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -100,6 +100,7 @@ module_param_named(flush_on_reuse, force_flush_and_sync_on_reuse, bool, 0644);
* If the hardware supports that we don't need to do shadow paging.
*/
bool tdp_enabled = false;
+EXPORT_SYMBOL_GPL(tdp_enabled);
static bool __ro_after_init tdp_mmu_allowed;
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 60fc4dfb22fd..a2065cfab50a 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -2,6 +2,7 @@
#include <linux/moduleparam.h>
#include "x86_ops.h"
+#include "mmu.h"
#include "vmx.h"
#include "nested.h"
#include "mmu.h"
@@ -57,6 +58,17 @@ static __init int vt_hardware_setup(void)
if (enable_ept)
kvm_mmu_set_ept_masks(enable_ept_ad_bits,
cpu_has_vmx_ept_execute_only());
+ /* TDX requires KVM TDP MMU. */
+ if (enable_tdx && !tdp_enabled) {
+ enable_tdx = false;
+ pr_warn_ratelimited("TDX requires TDP MMU. Please enable TDP MMU for TDX.\n");
+ }
+
+ /* TDX requires MMIO caching. */
+ if (enable_tdx && !enable_mmio_caching) {
+ enable_tdx = false;
+ pr_warn_ratelimited("TDX requires mmio caching. Please enable mmio caching for TDX.\n");
+ }
enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
--
2.25.1
From: Isaku Yamahata <[email protected]>
To make use of the same value of shadow_mmio_mask and shadow_present_mask
for TDX and VMX, add Suppress-VE bit to shadow_mmio_mask and
shadow_present_mask so that they can be common for both VMX and TDX.
TDX will require shadow_mmio_mask and shadow_present_mask to include
VMX_SUPPRESS_VE for shared GPA so that EPT violation is triggered for
shared GPA. For VMX, VMX_SUPPRESS_VE doesn't matter for MMIO because the
spte value is required to cause EPT misconfig. the additional bit doesn't
affect VMX logic to add the bit to shadow_mmio_{value, mask}.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/vmx.h | 1 +
arch/x86/kvm/mmu/spte.c | 6 ++++--
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 498dc600bd5c..cdbf12c1a83c 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -511,6 +511,7 @@ enum vmcs_field {
#define VMX_EPT_IPAT_BIT (1ull << 6)
#define VMX_EPT_ACCESS_BIT (1ull << 8)
#define VMX_EPT_DIRTY_BIT (1ull << 9)
+#define VMX_EPT_SUPPRESS_VE_BIT (1ull << 63)
#define VMX_EPT_RWX_MASK (VMX_EPT_READABLE_MASK | \
VMX_EPT_WRITABLE_MASK | \
VMX_EPT_EXECUTABLE_MASK)
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index c15bfca3ed15..41802e6d6f57 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -431,7 +431,9 @@ void kvm_mmu_set_ept_masks(bool has_ad_bits, bool has_exec_only)
shadow_dirty_mask = has_ad_bits ? VMX_EPT_DIRTY_BIT : 0ull;
shadow_nx_mask = 0ull;
shadow_x_mask = VMX_EPT_EXECUTABLE_MASK;
- shadow_present_mask = has_exec_only ? 0ull : VMX_EPT_READABLE_MASK;
+ /* VMX_EPT_SUPPRESS_VE_BIT is needed for W or X violation. */
+ shadow_present_mask =
+ (has_exec_only ? 0ull : VMX_EPT_READABLE_MASK) | VMX_EPT_SUPPRESS_VE_BIT;
/*
* EPT overrides the host MTRRs, and so KVM must program the desired
* memtype directly into the SPTEs. Note, this mask is just the mask
@@ -448,7 +450,7 @@ void kvm_mmu_set_ept_masks(bool has_ad_bits, bool has_exec_only)
* of an EPT paging-structure entry is 110b (write/execute).
*/
kvm_mmu_set_mmio_spte_mask(VMX_EPT_MISCONFIG_WX_VALUE,
- VMX_EPT_RWX_MASK, 0);
+ VMX_EPT_RWX_MASK | VMX_EPT_SUPPRESS_VE_BIT, 0);
}
EXPORT_SYMBOL_GPL(kvm_mmu_set_ept_masks);
--
2.25.1
From: Isaku Yamahata <[email protected]>
Implement hooks of TDP MMU for TDX backend. TLB flush, TLB shootdown,
propagating the change private EPT entry to Secure EPT and freeing Secure
EPT page. TLB flush handles both shared EPT and private EPT. It flushes
shared EPT same as VMX. It also waits for the TDX TLB shootdown. For the
hook to free Secure EPT page, unlinks the Secure EPT page from the Secure
EPT so that the page can be freed to OS.
Propagate the entry change to Secure EPT. The possible entry changes are
present -> non-present(zapping) and non-present -> present(population). On
population just link the Secure EPT page or the private guest page to the
Secure EPT by TDX SEAMCALL. Because TDP MMU allows concurrent
zapping/population, zapping requires synchronous TLB shoot down with the
frozen EPT entry. It zaps the secure entry, increments TLB counter, sends
IPI to remote vcpus to trigger TLB flush, and then unlinks the private
guest page from the Secure EPT. For simplicity, batched zapping with
exclude lock is handled as concurrent zapping. Although it's inefficient,
it can be optimized in the future.
For MMIO SPTE, the spte value changes as follows.
initial value (suppress VE bit is set)
-> Guest issues MMIO and triggers EPT violation
-> KVM updates SPTE value to MMIO value (suppress VE bit is cleared)
-> Guest MMIO resumes. It triggers VE exception in guest TD
-> Guest VE handler issues TDG.VP.VMCALL<MMIO>
-> KVM handles MMIO
-> Guest VE handler resumes its execution after MMIO instruction
Signed-off-by: Isaku Yamahata <[email protected]>
---
Changes v11 to v12
- removed tlb_remote_flush_with_range mothod. Instead disable TDX if
hyper-v support populate tlb_remote_flush and tlb_remote_flush_with_range
---
arch/x86/kvm/mmu/spte.c | 3 +-
arch/x86/kvm/vmx/main.c | 71 ++++++++-
arch/x86/kvm/vmx/tdx.c | 306 +++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 7 +
arch/x86/kvm/vmx/x86_ops.h | 4 +
5 files changed, 386 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index 72c7b8d27efb..180907ef26c7 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -74,7 +74,8 @@ u64 make_mmio_spte(struct kvm_vcpu *vcpu, u64 gfn, unsigned int access)
u64 spte = generation_mmio_spte_mask(gen);
u64 gpa = gfn << PAGE_SHIFT;
- WARN_ON_ONCE(!vcpu->kvm->arch.shadow_mmio_value);
+ WARN_ON_ONCE(!vcpu->kvm->arch.shadow_mmio_value &&
+ !kvm_gfn_shared_mask(vcpu->kvm));
access &= shadow_mmio_access_mask;
spte |= vcpu->kvm->arch.shadow_mmio_value | access;
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index a2065cfab50a..902b57506291 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -42,6 +42,7 @@ static int vt_max_vcpus(struct kvm *kvm)
return kvm->max_vcpus;
}
+static int vt_tlb_remote_flush(struct kvm *kvm);
static __init int vt_hardware_setup(void)
{
@@ -70,8 +71,22 @@ static __init int vt_hardware_setup(void)
pr_warn_ratelimited("TDX requires mmio caching. Please enable mmio caching for TDX.\n");
}
+ /*
+ * TDX KVM overrides tlb_remote_flush method and assumes
+ * tlb_remote_flush_with_range = NULL that falls back to
+ * tlb_remote_flush. Disable TDX if there are conflicts.
+ */
+ if (vt_x86_ops.tlb_remote_flush ||
+ vt_x86_ops.tlb_remote_flush_with_range) {
+ enable_tdx = false;
+ pr_warn_ratelimited("TDX requires baremetal. Not Supported on VMM guest.\n");
+ }
+
enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
+ if (enable_tdx)
+ vt_x86_ops.tlb_remote_flush = vt_tlb_remote_flush;
+
return 0;
}
@@ -154,6 +169,54 @@ static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vmx_vcpu_reset(vcpu, init_event);
}
+static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_flush_tlb(vcpu);
+ return;
+ }
+
+ vmx_flush_tlb_all(vcpu);
+}
+
+static void vt_flush_tlb_current(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_flush_tlb(vcpu);
+ return;
+ }
+
+ vmx_flush_tlb_current(vcpu);
+}
+
+static int vt_tlb_remote_flush(struct kvm *kvm)
+{
+ if (is_td(kvm))
+ return tdx_sept_tlb_remote_flush(kvm);
+
+ /*
+ * fallback to KVM_REQ_TLB_FLUSH.
+ * See kvm_arch_flush_remote_tlb() and kvm_flush_remote_tlbs().
+ */
+ return -EOPNOTSUPP;
+}
+
+static void vt_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
+{
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return;
+
+ vmx_flush_tlb_gva(vcpu, addr);
+}
+
+static void vt_flush_tlb_guest(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_flush_tlb_guest(vcpu);
+}
+
static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
int pgd_level)
{
@@ -246,10 +309,10 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.set_rflags = vmx_set_rflags,
.get_if_flag = vmx_get_if_flag,
- .flush_tlb_all = vmx_flush_tlb_all,
- .flush_tlb_current = vmx_flush_tlb_current,
- .flush_tlb_gva = vmx_flush_tlb_gva,
- .flush_tlb_guest = vmx_flush_tlb_guest,
+ .flush_tlb_all = vt_flush_tlb_all,
+ .flush_tlb_current = vt_flush_tlb_current,
+ .flush_tlb_gva = vt_flush_tlb_gva,
+ .flush_tlb_guest = vt_flush_tlb_guest,
.vcpu_pre_run = vmx_vcpu_pre_run,
.vcpu_run = vmx_vcpu_run,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 340034db15a7..6ab7580de69c 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -6,7 +6,9 @@
#include "capabilities.h"
#include "x86_ops.h"
#include "tdx.h"
+#include "vmx.h"
#include "x86.h"
+#include "mmu.h"
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -317,6 +319,22 @@ static int tdx_do_tdh_mng_key_config(void *param)
int tdx_vm_init(struct kvm *kvm)
{
+ /*
+ * Because guest TD is protected, VMM can't parse the instruction in TD.
+ * Instead, guest uses MMIO hypercall. For unmodified device driver,
+ * #VE needs to be injected for MMIO and #VE handler in TD converts MMIO
+ * instruction into MMIO hypercall.
+ *
+ * SPTE value for MMIO needs to be setup so that #VE is injected into
+ * TD instead of triggering EPT MISCONFIG.
+ * - RWX=0 so that EPT violation is triggered.
+ * - suppress #VE bit is cleared to inject #VE.
+ */
+ kvm_mmu_set_mmio_spte_value(kvm, 0);
+
+ /* TODO: Enable 2mb and 1gb large page support. */
+ kvm->arch.tdp_max_page_level = PG_LEVEL_4K;
+
/*
* This function initializes only KVM software construct. It doesn't
* initialize TDX stuff, e.g. TDCS, TDR, TDCX, HKID etc.
@@ -409,6 +427,261 @@ void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
}
+static void tdx_unpin(struct kvm *kvm, kvm_pfn_t pfn)
+{
+ struct page *page = pfn_to_page(pfn);
+
+ put_page(page);
+}
+
+static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
+ enum pg_level level, kvm_pfn_t pfn)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ hpa_t hpa = pfn_to_hpa(pfn);
+ gpa_t gpa = gfn_to_gpa(gfn);
+ struct tdx_module_output out;
+ u64 err;
+
+ /* TODO: handle large pages. */
+ if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
+ return -EINVAL;
+
+ /*
+ * Because restricted mem doesn't support page migration with
+ * a_ops->migrate_page (yet), no callback isn't triggered for KVM on
+ * page migration. Until restricted mem supports page migration,
+ * prevent page migration.
+ * TODO: Once restricted mem introduces callback on page migration,
+ * implement it and remove get_page/put_page().
+ */
+ get_page(pfn_to_page(pfn));
+
+ if (likely(is_td_finalized(kvm_tdx))) {
+ err = tdh_mem_page_aug(kvm_tdx->tdr_pa, gpa, hpa, &out);
+ if (err == TDX_ERROR_SEPT_BUSY) {
+ tdx_unpin(kvm, pfn);
+ return -EAGAIN;
+ }
+ if (KVM_BUG_ON(err, kvm)) {
+ pr_tdx_error(TDH_MEM_PAGE_AUG, err, &out);
+ tdx_unpin(kvm, pfn);
+ return -EIO;
+ }
+ return 0;
+ }
+
+ /* TODO: tdh_mem_page_add() comes here for the initial memory. */
+
+ return 0;
+}
+
+static int tdx_sept_drop_private_spte(struct kvm *kvm, gfn_t gfn,
+ enum pg_level level, kvm_pfn_t pfn)
+{
+ int tdx_level = pg_level_to_tdx_sept_level(level);
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ struct tdx_module_output out;
+ gpa_t gpa = gfn_to_gpa(gfn);
+ hpa_t hpa = pfn_to_hpa(pfn);
+ hpa_t hpa_with_hkid;
+ u64 err;
+
+ /* TODO: handle large pages. */
+ if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
+ return -EINVAL;
+
+ if (!is_hkid_assigned(kvm_tdx)) {
+ /*
+ * The HKID assigned to this TD was already freed and cache
+ * was already flushed. We don't have to flush again.
+ */
+ err = tdx_reclaim_page(hpa, false, 0);
+ if (KVM_BUG_ON(err, kvm))
+ return -EIO;
+ tdx_unpin(kvm, pfn);
+ return 0;
+ }
+
+ do {
+ /*
+ * When zapping private page, write lock is held. So no race
+ * condition with other vcpu sept operation. Race only with
+ * TDH.VP.ENTER.
+ */
+ err = tdh_mem_page_remove(kvm_tdx->tdr_pa, gpa, tdx_level, &out);
+ } while (err == TDX_ERROR_SEPT_BUSY);
+ if (KVM_BUG_ON(err, kvm)) {
+ pr_tdx_error(TDH_MEM_PAGE_REMOVE, err, &out);
+ return -EIO;
+ }
+
+ hpa_with_hkid = set_hkid_to_hpa(hpa, (u16)kvm_tdx->hkid);
+ do {
+ /*
+ * TDX_OPERAND_BUSY can happen on locking PAMT entry. Because
+ * this page was removed above, other thread shouldn't be
+ * repeatedly operating on this page. Just retry loop.
+ */
+ err = tdh_phymem_page_wbinvd(hpa_with_hkid);
+ } while (err == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_RCX));
+ if (KVM_BUG_ON(err, kvm)) {
+ pr_tdx_error(TDH_PHYMEM_PAGE_WBINVD, err, NULL);
+ return -EIO;
+ }
+ tdx_unpin(kvm, pfn);
+ return 0;
+}
+
+static int tdx_sept_link_private_spt(struct kvm *kvm, gfn_t gfn,
+ enum pg_level level, void *private_spt)
+{
+ int tdx_level = pg_level_to_tdx_sept_level(level);
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ gpa_t gpa = gfn_to_gpa(gfn);
+ hpa_t hpa = __pa(private_spt);
+ struct tdx_module_output out;
+ u64 err;
+
+ err = tdh_mem_sept_add(kvm_tdx->tdr_pa, gpa, tdx_level, hpa, &out);
+ if (err == TDX_ERROR_SEPT_BUSY)
+ return -EAGAIN;
+ if (KVM_BUG_ON(err, kvm)) {
+ pr_tdx_error(TDH_MEM_SEPT_ADD, err, &out);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int tdx_sept_zap_private_spte(struct kvm *kvm, gfn_t gfn,
+ enum pg_level level)
+{
+ int tdx_level = pg_level_to_tdx_sept_level(level);
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ gpa_t gpa = gfn_to_gpa(gfn);
+ struct tdx_module_output out;
+ u64 err;
+
+ /* For now large page isn't supported yet. */
+ WARN_ON_ONCE(level != PG_LEVEL_4K);
+ err = tdh_mem_range_block(kvm_tdx->tdr_pa, gpa, tdx_level, &out);
+ if (err == TDX_ERROR_SEPT_BUSY)
+ return -EAGAIN;
+ if (KVM_BUG_ON(err, kvm)) {
+ pr_tdx_error(TDH_MEM_RANGE_BLOCK, err, &out);
+ return -EIO;
+ }
+ return 0;
+}
+
+/*
+ * TLB shoot down procedure:
+ * There is a global epoch counter and each vcpu has local epoch counter.
+ * - TDH.MEM.RANGE.BLOCK(TDR. level, range) on one vcpu
+ * This blocks the subsequenct creation of TLB translation on that range.
+ * This corresponds to clear the present bit(all RXW) in EPT entry
+ * - TDH.MEM.TRACK(TDR): advances the epoch counter which is global.
+ * - IPI to remote vcpus
+ * - TDExit and re-entry with TDH.VP.ENTER on remote vcpus
+ * - On re-entry, TDX module compares the local epoch counter with the global
+ * epoch counter. If the local epoch counter is older than the global epoch
+ * counter, update the local epoch counter and flushes TLB.
+ */
+static void tdx_track(struct kvm_tdx *kvm_tdx)
+{
+ u64 err;
+
+ KVM_BUG_ON(!is_hkid_assigned(kvm_tdx), &kvm_tdx->kvm);
+ /* If TD isn't finalized, it's before any vcpu running. */
+ if (unlikely(!is_td_finalized(kvm_tdx)))
+ return;
+
+ /*
+ * tdx_flush_tlb() waits for this function to issue TDH.MEM.TRACK() by
+ * the counter. The counter is used instead of bool because multiple
+ * TDH_MEM_TRACK() can be issued concurrently by multiple vcpus.
+ */
+ atomic_inc(&kvm_tdx->tdh_mem_track);
+ /*
+ * KVM_REQ_TLB_FLUSH waits for the empty IPI handler, ack_flush(), with
+ * KVM_REQUEST_WAIT.
+ */
+ kvm_make_all_cpus_request(&kvm_tdx->kvm, KVM_REQ_TLB_FLUSH);
+
+ do {
+ /*
+ * kvm_flush_remote_tlbs() doesn't allow to return error and
+ * retry.
+ */
+ err = tdh_mem_track(kvm_tdx->tdr_pa);
+ } while ((err & TDX_SEAMCALL_STATUS_MASK) == TDX_OPERAND_BUSY);
+
+ /* Release remote vcpu waiting for TDH.MEM.TRACK in tdx_flush_tlb(). */
+ atomic_dec(&kvm_tdx->tdh_mem_track);
+
+ if (KVM_BUG_ON(err, &kvm_tdx->kvm))
+ pr_tdx_error(TDH_MEM_TRACK, err, NULL);
+
+}
+
+static int tdx_sept_free_private_spt(struct kvm *kvm, gfn_t gfn,
+ enum pg_level level, void *private_spt)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+
+ /*
+ * The HKID assigned to this TD was already freed and cache was
+ * already flushed. We don't have to flush again.
+ */
+ if (!is_hkid_assigned(kvm_tdx))
+ return tdx_reclaim_page(__pa(private_spt), false, 0);
+
+ /*
+ * free_private_spt() is (obviously) called when a shadow page is being
+ * zapped. KVM doesn't (yet) zap private SPs while the TD is active.
+ * Note: This function is for private shadow page. Not for private
+ * guest page. private guest page can be zapped during TD is active.
+ * shared <-> private conversion and slot move/deletion.
+ */
+ KVM_BUG_ON(is_hkid_assigned(kvm_tdx), kvm);
+ return -EINVAL;
+}
+
+int tdx_sept_tlb_remote_flush(struct kvm *kvm)
+{
+ struct kvm_tdx *kvm_tdx;
+
+ if (!is_td(kvm))
+ return -EOPNOTSUPP;
+
+ kvm_tdx = to_kvm_tdx(kvm);
+ if (is_hkid_assigned(kvm_tdx))
+ tdx_track(kvm_tdx);
+
+ return 0;
+}
+
+static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn,
+ enum pg_level level, kvm_pfn_t pfn)
+{
+ /*
+ * TDX requires TLB tracking before dropping private page. Do
+ * it here, although it is also done later.
+ * If hkid isn't assigned, the guest is destroying and no vcpu
+ * runs further. TLB shootdown isn't needed.
+ *
+ * TODO: implement with_range version for optimization.
+ * kvm_flush_remote_tlbs_with_address(kvm, gfn, 1);
+ * => tdx_sept_tlb_remote_flush_with_range(kvm, gfn,
+ * KVM_PAGES_PER_HPAGE(level));
+ */
+ if (is_hkid_assigned(to_kvm_tdx(kvm)))
+ kvm_flush_remote_tlbs(kvm);
+
+ return tdx_sept_drop_private_spte(kvm, gfn, level, pfn);
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
@@ -843,6 +1116,25 @@ static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd)
return ret;
}
+void tdx_flush_tlb(struct kvm_vcpu *vcpu)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct kvm_mmu *mmu = vcpu->arch.mmu;
+ u64 root_hpa = mmu->root.hpa;
+
+ /* Flush the shared EPTP, if it's valid. */
+ if (VALID_PAGE(root_hpa))
+ ept_sync_context(construct_eptp(vcpu, root_hpa,
+ mmu->root_role.level));
+
+ /*
+ * See tdx_track(). Wait for tlb shootdown initiater to finish
+ * TDH_MEM_TRACK() so that TLB is flushed on the next TDENTER.
+ */
+ while (atomic_read(&kvm_tdx->tdh_mem_track))
+ cpu_relax();
+}
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_tdx_cmd tdx_cmd;
@@ -1081,7 +1373,21 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
}
vmxoff_all();
cpus_read_unlock();
+ if (r)
+ goto out;
+
+ x86_ops->link_private_spt = tdx_sept_link_private_spt;
+ x86_ops->free_private_spt = tdx_sept_free_private_spt;
+ x86_ops->set_private_spte = tdx_sept_set_private_spte;
+ x86_ops->remove_private_spte = tdx_sept_remove_private_spte;
+ x86_ops->zap_private_spte = tdx_sept_zap_private_spte;
+
+ return 0;
+out:
+ /* kfree accepts NULL. */
+ kfree(tdx_mng_key_config_lock);
+ tdx_mng_key_config_lock = NULL;
return r;
}
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 7c8f5880d104..7acd708bffa8 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -18,6 +18,7 @@ struct kvm_tdx {
int hkid;
bool finalized;
+ atomic_t tdh_mem_track;
u64 tsc_offset;
};
@@ -165,6 +166,12 @@ static __always_inline u64 td_tdcs_exec_read64(struct kvm_tdx *kvm_tdx, u32 fiel
return out.r8;
}
+static __always_inline int pg_level_to_tdx_sept_level(enum pg_level level)
+{
+ WARN_ON_ONCE(level == PG_LEVEL_NONE);
+ return level - 1;
+}
+
#else
struct kvm_tdx {
struct kvm kvm;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 89d18369b117..b73007586d8b 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -158,6 +158,8 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
+void tdx_flush_tlb(struct kvm_vcpu *vcpu);
+int tdx_sept_tlb_remote_flush(struct kvm *kvm);
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
#else
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
@@ -181,6 +183,8 @@ static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
+static inline void tdx_flush_tlb(struct kvm_vcpu *vcpu) {}
+static inline int tdx_sept_tlb_remote_flush(struct kvm *kvm) { return 0; }
static inline void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level) {}
#endif
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because TDX virtualize cpuid[0x1].EDX[MTRR: bit 12] to fixed 1, guest TD
thinks MTRR is supported. Although TDX supports only WB for private GPA,
it's desirable to support MTRR for shared GPA. As guest access to MTRR
MSRs causes #VE and KVM/x86 tracks the values of MTRR MSRs, the remining
part is to implement get_mt_mask method for TDX for shared GPA.
Pass around shared bit from kvm fault handler to get_mt_mask method so that
it can determine if the gfn is shared or private. Implement get_mt_mask()
following vmx case for shared GPA and return WB for private GPA.
the existing vmx_get_mt_mask() can't be directly used as CPU state(CR0.CD)
is protected. GFN passed to kvm_mtrr_check_gfn_range_consistency() should
include shared bit.
Suggested-by: Kai Huang <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
Changes from v11 to V12
- Make common function for VMX and TDX
- pass around shared bit from KVM fault handler to get_mt_mask method
- updated commit message
---
arch/x86/kvm/mmu/mmu.c | 7 ++++++-
arch/x86/kvm/mmu/spte.c | 5 +++--
arch/x86/kvm/mmu/spte.h | 2 +-
arch/x86/kvm/vmx/common.h | 2 ++
arch/x86/kvm/vmx/main.c | 11 ++++++++++-
arch/x86/kvm/vmx/tdx.c | 17 +++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 5 +++--
arch/x86/kvm/vmx/x86_ops.h | 2 ++
8 files changed, 44 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 6074aa09cd87..fb858594cfec 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4569,7 +4569,12 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
if (shadow_memtype_mask && kvm_arch_has_noncoherent_dma(vcpu->kvm)) {
for ( ; fault->max_level > PG_LEVEL_4K; --fault->max_level) {
int page_num = KVM_PAGES_PER_HPAGE(fault->max_level);
- gfn_t base = gfn_round_for_level(fault->gfn,
+ /*
+ * kvm_mtrr_check_gfn_range_consistency() requires gfn
+ * including shared bit. fault->gfn is masked out with
+ * shared bit. So fault->gfn can't be used.
+ */
+ gfn_t base = gfn_round_for_level(gpa_to_gfn(fault->addr),
fault->max_level);
if (kvm_mtrr_check_gfn_range_consistency(vcpu, base, page_num))
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index 180907ef26c7..7adb0d00ec4b 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -137,13 +137,14 @@ bool spte_has_volatile_bits(u64 spte)
bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
const struct kvm_memory_slot *slot,
- unsigned int pte_access, gfn_t gfn, kvm_pfn_t pfn,
+ unsigned int pte_access, gfn_t gfn_including_shared, kvm_pfn_t pfn,
u64 old_spte, bool prefetch, bool can_unsync,
bool host_writable, u64 *new_spte)
{
int level = sp->role.level;
u64 spte = SPTE_MMU_PRESENT_MASK;
bool wrprot = false;
+ gfn_t gfn = gfn_including_shared & ~kvm_gfn_shared_mask(vcpu->kvm);
WARN_ON_ONCE(!pte_access && !shadow_present_mask);
@@ -191,7 +192,7 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
spte |= PT_PAGE_SIZE_MASK;
if (shadow_memtype_mask)
- spte |= static_call(kvm_x86_get_mt_mask)(vcpu, gfn,
+ spte |= static_call(kvm_x86_get_mt_mask)(vcpu, gfn_including_shared,
kvm_is_mmio_pfn(pfn));
if (host_writable)
spte |= shadow_host_writable_mask;
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index 41973fe6bc22..62280c4b8c81 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -481,7 +481,7 @@ bool spte_has_volatile_bits(u64 spte);
bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
const struct kvm_memory_slot *slot,
- unsigned int pte_access, gfn_t gfn, kvm_pfn_t pfn,
+ unsigned int pte_access, gfn_t gfn_including_shared, kvm_pfn_t pfn,
u64 old_spte, bool prefetch, bool can_unsync,
bool host_writable, u64 *new_spte);
u64 make_huge_page_split_spte(struct kvm *kvm, u64 huge_spte,
diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
index 235908f3e044..422b24af7fc1 100644
--- a/arch/x86/kvm/vmx/common.h
+++ b/arch/x86/kvm/vmx/common.h
@@ -6,6 +6,8 @@
#include "mmu.h"
+u8 __vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio, bool check_cr0_cd);
+
static inline int __vmx_handle_ept_violation(struct kvm_vcpu *vcpu, gpa_t gpa,
unsigned long exit_qualification)
{
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 902b57506291..55001b34e1f0 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -3,6 +3,7 @@
#include "x86_ops.h"
#include "mmu.h"
+#include "common.h"
#include "vmx.h"
#include "nested.h"
#include "mmu.h"
@@ -228,6 +229,14 @@ static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
}
+static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_get_mt_mask(vcpu, gfn, is_mmio);
+
+ return __vmx_get_mt_mask(vcpu, gfn, is_mmio, true);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -348,7 +357,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.set_tss_addr = vmx_set_tss_addr,
.set_identity_map_addr = vmx_set_identity_map_addr,
- .get_mt_mask = vmx_get_mt_mask,
+ .get_mt_mask = vt_get_mt_mask,
.get_exit_info = vmx_get_exit_info,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 6ab7580de69c..b7b4ab60f96d 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -5,6 +5,7 @@
#include "capabilities.h"
#include "x86_ops.h"
+#include "common.h"
#include "tdx.h"
#include "vmx.h"
#include "x86.h"
@@ -350,6 +351,22 @@ int tdx_vm_init(struct kvm *kvm)
return 0;
}
+u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+{
+ /* TDX private GPA is always WB. */
+ if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
+ /* MMIO is only for shared GPA. */
+ WARN_ON_ONCE(is_mmio);
+ return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
+ }
+
+ /* Drop shared bit as MTRR doesn't know about shared bit. */
+ gfn = kvm_gfn_to_private(vcpu->kvm, gfn);
+
+ /* As TDX enforces CR0.CD to 0, pass check_cr0_cd = false. */
+ return __vmx_get_mt_mask(vcpu, gfn, is_mmio, false);
+}
+
int tdx_vcpu_create(struct kvm_vcpu *vcpu)
{
/*
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 23321b2208ae..b8d8f7fbeb69 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7568,7 +7568,8 @@ int vmx_vm_init(struct kvm *kvm)
return 0;
}
-u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+u8 __vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio,
+ bool check_cr0_cd)
{
u8 cache;
@@ -7596,7 +7597,7 @@ u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))
return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;
- if (kvm_read_cr0(vcpu) & X86_CR0_CD) {
+ if (check_cr0_cd && kvm_read_cr0(vcpu) & X86_CR0_CD) {
if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED))
cache = MTRR_TYPE_WRBACK;
else
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index b73007586d8b..eba10dabc45f 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -155,6 +155,7 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
+u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -180,6 +181,7 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP
static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
+static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TD finalization.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index c4d67dd9ddf8..46ae049b6b85 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -11,6 +11,7 @@ What qemu can do
- TDX VM TYPE is exposed to Qemu.
- Qemu can create/destroy guest of TDX vm type.
- Qemu can create/destroy vcpu of TDX vm type.
+- Qemu can populate initial guest memory image.
Patch Layer status
------------------
@@ -20,8 +21,8 @@ Patch Layer status
* TDX architectural definitions: Applied
* TD VM creation/destruction: Applied
* TD vcpu creation/destruction: Applied
-* TDX EPT violation: Applying
-* TD finalization: Not yet
+* TDX EPT violation: Applied
+* TD finalization: Applying
* TD vcpu enter/exit: Not yet
* TD vcpu interrupts/exit/hypercall: Not yet
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX will use a different shadow PTE entry value for MMIO from VMX. Add
members to kvm_arch and track value for MMIO per-VM instead of global
variables. By using the per-VM EPT entry value for MMIO, the existing VMX
logic is kept working. Introduce a separate setter function so that guest
TD can override later.
Also require mmio spte cachcing for TDX. Actually this is true case
because TDX require EPT and KVM EPT allows mmio spte caching.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/mmu.h | 1 +
arch/x86/kvm/mmu/mmu.c | 7 ++++---
arch/x86/kvm/mmu/spte.c | 10 ++++++++--
arch/x86/kvm/mmu/spte.h | 4 ++--
arch/x86/kvm/mmu/tdp_mmu.c | 6 +++---
6 files changed, 20 insertions(+), 10 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1802ee8bf1ad..0fdd432e62e2 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1276,6 +1276,8 @@ struct kvm_arch {
*/
spinlock_t mmu_unsync_pages_lock;
+ u64 shadow_mmio_value;
+
struct list_head assigned_dev_head;
struct iommu_domain *iommu_domain;
bool iommu_noncoherent;
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 34a7266f145f..0ecdad63ad8c 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -101,6 +101,7 @@ static inline u8 kvm_get_shadow_phys_bits(void)
}
void kvm_mmu_set_mmio_spte_mask(u64 mmio_value, u64 mmio_mask, u64 access_mask);
+void kvm_mmu_set_mmio_spte_value(struct kvm *kvm, u64 mmio_value);
void kvm_mmu_set_me_spte_mask(u64 me_value, u64 me_mask);
void kvm_mmu_set_ept_masks(bool has_ad_bits, bool has_exec_only);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 6026c5c130d4..9bc640e0d821 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2455,7 +2455,7 @@ static int mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp,
return kvm_mmu_prepare_zap_page(kvm, child,
invalid_list);
}
- } else if (is_mmio_spte(pte)) {
+ } else if (is_mmio_spte(kvm, pte)) {
mmu_spte_clear_no_track(spte);
}
return 0;
@@ -4135,7 +4135,7 @@ static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct)
if (WARN_ON(reserved))
return -EINVAL;
- if (is_mmio_spte(spte)) {
+ if (is_mmio_spte(vcpu->kvm, spte)) {
gfn_t gfn = get_mmio_spte_gfn(spte);
unsigned int access = get_mmio_spte_access(spte);
@@ -4686,7 +4686,7 @@ static unsigned long get_cr3(struct kvm_vcpu *vcpu)
static bool sync_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn,
unsigned int access)
{
- if (unlikely(is_mmio_spte(*sptep))) {
+ if (unlikely(is_mmio_spte(vcpu->kvm, *sptep))) {
if (gfn != get_mmio_spte_gfn(*sptep)) {
mmu_spte_clear_no_track(sptep);
return true;
@@ -6175,6 +6175,7 @@ int kvm_mmu_init_vm(struct kvm *kvm)
struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker;
int r;
+ kvm->arch.shadow_mmio_value = shadow_mmio_value;
INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages);
INIT_LIST_HEAD(&kvm->arch.possible_nx_huge_pages);
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index 41802e6d6f57..72c7b8d27efb 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -74,10 +74,10 @@ u64 make_mmio_spte(struct kvm_vcpu *vcpu, u64 gfn, unsigned int access)
u64 spte = generation_mmio_spte_mask(gen);
u64 gpa = gfn << PAGE_SHIFT;
- WARN_ON_ONCE(!shadow_mmio_value);
+ WARN_ON_ONCE(!vcpu->kvm->arch.shadow_mmio_value);
access &= shadow_mmio_access_mask;
- spte |= shadow_mmio_value | access;
+ spte |= vcpu->kvm->arch.shadow_mmio_value | access;
spte |= gpa | shadow_nonpresent_or_rsvd_mask;
spte |= (gpa & shadow_nonpresent_or_rsvd_mask)
<< SHADOW_NONPRESENT_OR_RSVD_MASK_LEN;
@@ -413,6 +413,12 @@ void kvm_mmu_set_mmio_spte_mask(u64 mmio_value, u64 mmio_mask, u64 access_mask)
}
EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_mask);
+void kvm_mmu_set_mmio_spte_value(struct kvm *kvm, u64 mmio_value)
+{
+ kvm->arch.shadow_mmio_value = mmio_value;
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_value);
+
void kvm_mmu_set_me_spte_mask(u64 me_value, u64 me_mask)
{
/* shadow_me_value must be a subset of shadow_me_mask */
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index a57667810344..a8418fd8ae9e 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -251,9 +251,9 @@ static inline struct kvm_mmu_page *sptep_to_sp(u64 *sptep)
return to_shadow_page(__pa(sptep));
}
-static inline bool is_mmio_spte(u64 spte)
+static inline bool is_mmio_spte(struct kvm *kvm, u64 spte)
{
- return (spte & shadow_mmio_mask) == shadow_mmio_value &&
+ return (spte & shadow_mmio_mask) == kvm->arch.shadow_mmio_value &&
likely(enable_mmio_caching);
}
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 76e3751c8e9d..b342ce3a6e83 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -576,8 +576,8 @@ static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
* impact the guest since both the former and current SPTEs
* are nonpresent.
*/
- if (WARN_ON(!is_mmio_spte(old_spte) &&
- !is_mmio_spte(new_spte) &&
+ if (WARN_ON(!is_mmio_spte(kvm, old_spte) &&
+ !is_mmio_spte(kvm, new_spte) &&
!is_removed_spte(new_spte)))
pr_err("Unexpected SPTE change! Nonpresent SPTEs\n"
"should not be replaced with another,\n"
@@ -1093,7 +1093,7 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu,
}
/* If a MMIO SPTE is installed, the MMIO will need to be emulated. */
- if (unlikely(is_mmio_spte(new_spte))) {
+ if (unlikely(is_mmio_spte(vcpu->kvm, new_spte))) {
vcpu->stat.pf_mmio_spte_created++;
trace_mark_mmio_spte(rcu_dereference(iter->sptep), iter->gfn,
new_spte);
--
2.25.1
From: Sean Christopherson <[email protected]>
Introduce a helper to directly (pun intended) fault-in a TDP page
without having to go through the full page fault path. This allows
TDX to get the resulting pfn and also allows the RET_PF_* enums to
stay in mmu.c where they belong.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu.h | 3 +++
arch/x86/kvm/mmu/mmu.c | 49 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 52 insertions(+)
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 0ecdad63ad8c..d10b08eeaefe 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -154,6 +154,9 @@ static inline void kvm_mmu_load_pgd(struct kvm_vcpu *vcpu)
vcpu->arch.mmu->root_role.level);
}
+kvm_pfn_t kvm_mmu_map_tdp_page(struct kvm_vcpu *vcpu, gpa_t gpa,
+ u32 error_code, int max_level);
+
/*
* Check if a given access (described through the I/D, W/R and U/S bits of a
* page fault error code pfec) causes a permission fault with the given PTE
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index fb858594cfec..d4596b7594fa 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4590,6 +4590,55 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
return direct_page_fault(vcpu, fault);
}
+kvm_pfn_t kvm_mmu_map_tdp_page(struct kvm_vcpu *vcpu, gpa_t gpa,
+ u32 error_code, int max_level)
+{
+ int r;
+ struct kvm_page_fault fault = (struct kvm_page_fault) {
+ .addr = gpa,
+ .error_code = error_code,
+ .exec = error_code & PFERR_FETCH_MASK,
+ .write = error_code & PFERR_WRITE_MASK,
+ .present = error_code & PFERR_PRESENT_MASK,
+ .rsvd = error_code & PFERR_RSVD_MASK,
+ .user = error_code & PFERR_USER_MASK,
+ .prefetch = false,
+ .is_tdp = true,
+ .nx_huge_page_workaround_enabled = is_nx_huge_page_enabled(vcpu->kvm),
+ .is_private = kvm_is_private_gpa(vcpu->kvm, gpa),
+ };
+
+ WARN_ON_ONCE(!vcpu->arch.mmu->root_role.direct);
+ fault.gfn = gpa_to_gfn(fault.addr) & ~kvm_gfn_shared_mask(vcpu->kvm);
+ fault.slot = kvm_vcpu_gfn_to_memslot(vcpu, fault.gfn);
+
+ if (mmu_topup_memory_caches(vcpu, false))
+ return KVM_PFN_ERR_FAULT;
+
+ /*
+ * Loop on the page fault path to handle the case where an mmu_notifier
+ * invalidation triggers RET_PF_RETRY. In the normal page fault path,
+ * KVM needs to resume the guest in case the invalidation changed any
+ * of the page fault properties, i.e. the gpa or error code. For this
+ * path, the gpa and error code are fixed by the caller, and the caller
+ * expects failure if and only if the page fault can't be fixed.
+ */
+ do {
+ fault.max_level = max_level;
+ fault.req_level = PG_LEVEL_4K;
+ fault.goal_level = PG_LEVEL_4K;
+
+#ifdef CONFIG_X86_64
+ if (tdp_mmu_enabled)
+ r = kvm_tdp_mmu_page_fault(vcpu, &fault);
+ else
+#endif
+ r = direct_page_fault(vcpu, &fault);
+ } while (r == RET_PF_RETRY && !is_error_noslot_pfn(fault.pfn));
+ return fault.pfn;
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_map_tdp_page);
+
static void nonpaging_init_context(struct kvm_mmu *context)
{
context->page_fault = nonpaging_page_fault;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because the guest memory is protected in TDX, the creation of the initial
guest memory requires a dedicated TDX module API, tdh_mem_page_add, instead
of directly copying the memory contents into the guest memory in the case
of the default VM type. KVM MMU page fault handler callback,
private_page_add, handles it.
Define new subcommand, KVM_TDX_INIT_MEM_REGION, of VM-scoped
KVM_MEMORY_ENCRYPT_OP. It assigns the guest page, copies the initial
memory contents into the guest memory, encrypts the guest memory. At the
same time, optionally it extends memory measurement of the TDX guest. It
calls the KVM MMU page fault(EPT-violation) handler to trigger the
callbacks for it.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/uapi/asm/kvm.h | 9 ++
arch/x86/kvm/mmu/mmu.c | 1 +
arch/x86/kvm/vmx/tdx.c | 156 +++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 2 +
tools/arch/x86/include/uapi/asm/kvm.h | 9 ++
5 files changed, 172 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index da7078cd7d7d..74148437ceac 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -567,6 +567,7 @@ enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
KVM_TDX_INIT_VM,
KVM_TDX_INIT_VCPU,
+ KVM_TDX_INIT_MEM_REGION,
KVM_TDX_CMD_NR_MAX,
};
@@ -635,4 +636,12 @@ struct kvm_tdx_init_vm {
struct kvm_cpuid2 cpuid;
};
+#define KVM_TDX_MEASURE_MEMORY_REGION (1UL << 0)
+
+struct kvm_tdx_init_mem_region {
+ __u64 source_addr;
+ __u64 gpa;
+ __u64 nr_pages;
+};
+
#endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index d4596b7594fa..a35f2e7f9bc7 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5609,6 +5609,7 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
out:
return r;
}
+EXPORT_SYMBOL(kvm_mmu_load);
void kvm_mmu_unload(struct kvm_vcpu *vcpu)
{
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index b7b4ab60f96d..8e7dc4c70af0 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -444,6 +444,21 @@ void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
}
+static void tdx_measure_page(struct kvm_tdx *kvm_tdx, hpa_t gpa)
+{
+ struct tdx_module_output out;
+ u64 err;
+ int i;
+
+ for (i = 0; i < PAGE_SIZE; i += TDX_EXTENDMR_CHUNKSIZE) {
+ err = tdh_mr_extend(kvm_tdx->tdr_pa, gpa + i, &out);
+ if (KVM_BUG_ON(err, &kvm_tdx->kvm)) {
+ pr_tdx_error(TDH_MR_EXTEND, err, &out);
+ break;
+ }
+ }
+}
+
static void tdx_unpin(struct kvm *kvm, kvm_pfn_t pfn)
{
struct page *page = pfn_to_page(pfn);
@@ -458,12 +473,10 @@ static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
hpa_t hpa = pfn_to_hpa(pfn);
gpa_t gpa = gfn_to_gpa(gfn);
struct tdx_module_output out;
+ hpa_t source_pa;
+ bool measure;
u64 err;
- /* TODO: handle large pages. */
- if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
- return -EINVAL;
-
/*
* Because restricted mem doesn't support page migration with
* a_ops->migrate_page (yet), no callback isn't triggered for KVM on
@@ -474,7 +487,12 @@ static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
*/
get_page(pfn_to_page(pfn));
+ /* Build-time faults are induced and handled via TDH_MEM_PAGE_ADD. */
if (likely(is_td_finalized(kvm_tdx))) {
+ /* TODO: handle large pages. */
+ if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
+ return -EINVAL;
+
err = tdh_mem_page_aug(kvm_tdx->tdr_pa, gpa, hpa, &out);
if (err == TDX_ERROR_SEPT_BUSY) {
tdx_unpin(kvm, pfn);
@@ -488,7 +506,45 @@ static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
return 0;
}
- /* TODO: tdh_mem_page_add() comes here for the initial memory. */
+ /*
+ * KVM_INIT_MEM_REGION, tdx_init_mem_region(), supports only 4K page
+ * because tdh_mem_page_add() supports only 4K page.
+ */
+ if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
+ return -EINVAL;
+
+ /*
+ * In case of TDP MMU, fault handler can run concurrently. Note
+ * 'source_pa' is a TD scope variable, meaning if there are multiple
+ * threads reaching here with all needing to access 'source_pa', it
+ * will break. However fortunately this won't happen, because below
+ * TDH_MEM_PAGE_ADD code path is only used when VM is being created
+ * before it is running, using KVM_TDX_INIT_MEM_REGION ioctl (which
+ * always uses vcpu 0's page table and protected by vcpu->mutex).
+ */
+ if (KVM_BUG_ON(kvm_tdx->source_pa == INVALID_PAGE, kvm)) {
+ tdx_unpin(kvm, pfn);
+ return -EINVAL;
+ }
+
+ source_pa = kvm_tdx->source_pa & ~KVM_TDX_MEASURE_MEMORY_REGION;
+ measure = kvm_tdx->source_pa & KVM_TDX_MEASURE_MEMORY_REGION;
+ kvm_tdx->source_pa = INVALID_PAGE;
+
+ do {
+ err = tdh_mem_page_add(kvm_tdx->tdr_pa, gpa, hpa, source_pa,
+ &out);
+ /*
+ * This path is executed during populating initial guest memory
+ * image. i.e. before running any vcpu. Race is rare.
+ */
+ } while (err == TDX_ERROR_SEPT_BUSY);
+ if (KVM_BUG_ON(err, kvm)) {
+ pr_tdx_error(TDH_MEM_PAGE_ADD, err, &out);
+ tdx_unpin(kvm, pfn);
+ return -EIO;
+ } else if (measure)
+ tdx_measure_page(kvm_tdx, gpa);
return 0;
}
@@ -1152,6 +1208,93 @@ void tdx_flush_tlb(struct kvm_vcpu *vcpu)
cpu_relax();
}
+#define TDX_SEPT_PFERR PFERR_WRITE_MASK
+
+static int tdx_init_mem_region(struct kvm *kvm, struct kvm_tdx_cmd *cmd)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ struct kvm_tdx_init_mem_region region;
+ struct kvm_vcpu *vcpu;
+ struct page *page;
+ kvm_pfn_t pfn;
+ int idx, ret = 0;
+
+ /* The BSP vCPU must be created before initializing memory regions. */
+ if (!atomic_read(&kvm->online_vcpus))
+ return -EINVAL;
+
+ if (cmd->flags & ~KVM_TDX_MEASURE_MEMORY_REGION)
+ return -EINVAL;
+
+ if (copy_from_user(®ion, (void __user *)cmd->data, sizeof(region)))
+ return -EFAULT;
+
+ /* Sanity check */
+ if (!IS_ALIGNED(region.source_addr, PAGE_SIZE) ||
+ !IS_ALIGNED(region.gpa, PAGE_SIZE) ||
+ !region.nr_pages ||
+ region.gpa + (region.nr_pages << PAGE_SHIFT) <= region.gpa ||
+ !kvm_is_private_gpa(kvm, region.gpa) ||
+ !kvm_is_private_gpa(kvm, region.gpa + (region.nr_pages << PAGE_SHIFT)))
+ return -EINVAL;
+
+ vcpu = kvm_get_vcpu(kvm, 0);
+ if (mutex_lock_killable(&vcpu->mutex))
+ return -EINTR;
+
+ vcpu_load(vcpu);
+ idx = srcu_read_lock(&kvm->srcu);
+
+ kvm_mmu_reload(vcpu);
+
+ while (region.nr_pages) {
+ if (signal_pending(current)) {
+ ret = -ERESTARTSYS;
+ break;
+ }
+
+ if (need_resched())
+ cond_resched();
+
+ /* Pin the source page. */
+ ret = get_user_pages_fast(region.source_addr, 1, 0, &page);
+ if (ret < 0)
+ break;
+ if (ret != 1) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ kvm_tdx->source_pa = pfn_to_hpa(page_to_pfn(page)) |
+ (cmd->flags & KVM_TDX_MEASURE_MEMORY_REGION);
+
+ pfn = kvm_mmu_map_tdp_page(vcpu, region.gpa, TDX_SEPT_PFERR,
+ PG_LEVEL_4K);
+ if (is_error_noslot_pfn(pfn) || kvm->vm_bugged)
+ ret = -EFAULT;
+ else
+ ret = 0;
+
+ put_page(page);
+ if (ret)
+ break;
+
+ region.source_addr += PAGE_SIZE;
+ region.gpa += PAGE_SIZE;
+ region.nr_pages--;
+ }
+
+ srcu_read_unlock(&kvm->srcu, idx);
+ vcpu_put(vcpu);
+
+ mutex_unlock(&vcpu->mutex);
+
+ if (copy_to_user((void __user *)cmd->data, ®ion, sizeof(region)))
+ ret = -EFAULT;
+
+ return ret;
+}
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_tdx_cmd tdx_cmd;
@@ -1168,6 +1311,9 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
case KVM_TDX_INIT_VM:
r = tdx_td_init(kvm, &tdx_cmd);
break;
+ case KVM_TDX_INIT_MEM_REGION:
+ r = tdx_init_mem_region(kvm, &tdx_cmd);
+ break;
default:
r = -EINVAL;
goto out;
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 7acd708bffa8..9d8445324841 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -17,6 +17,8 @@ struct kvm_tdx {
u64 xfam;
int hkid;
+ hpa_t source_pa;
+
bool finalized;
atomic_t tdh_mem_track;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 0f88e32d02a8..a7d4d8fe9ca8 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -567,6 +567,7 @@ enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
KVM_TDX_INIT_VM,
KVM_TDX_INIT_VCPU,
+ KVM_TDX_INIT_MEM_REGION,
KVM_TDX_CMD_NR_MAX,
};
@@ -644,4 +645,12 @@ struct kvm_tdx_init_vm {
};
};
+#define KVM_TDX_MEASURE_MEMORY_REGION (1UL << 0)
+
+struct kvm_tdx_init_mem_region {
+ __u64 source_addr;
+ __u64 gpa;
+ __u64 nr_pages;
+};
+
#endif /* _ASM_X86_KVM_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
To protect the initial contents of the guest TD, the TDX module measures
the guest TD during the build process as SHA-384 measurement. The
measurement of the guest TD contents needs to be completed to make the
guest TD ready to run.
Add a new subcommand, KVM_TDX_FINALIZE_VM, for VM-scoped
KVM_MEMORY_ENCRYPT_OP to finalize the measurement and mark the TDX VM ready
to run.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/uapi/asm/kvm.h | 1 +
arch/x86/kvm/vmx/tdx.c | 31 +++++++++++++++++++++++++++
tools/arch/x86/include/uapi/asm/kvm.h | 1 +
3 files changed, 33 insertions(+)
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 74148437ceac..445cf19d5f96 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -568,6 +568,7 @@ enum kvm_tdx_cmd_id {
KVM_TDX_INIT_VM,
KVM_TDX_INIT_VCPU,
KVM_TDX_INIT_MEM_REGION,
+ KVM_TDX_FINALIZE_VM,
KVM_TDX_CMD_NR_MAX,
};
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 8e7dc4c70af0..d5a2f769a58d 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1295,6 +1295,34 @@ static int tdx_init_mem_region(struct kvm *kvm, struct kvm_tdx_cmd *cmd)
return ret;
}
+static int tdx_td_finalizemr(struct kvm *kvm)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
+ u64 err;
+
+ if (!is_hkid_assigned(kvm_tdx) || is_td_finalized(kvm_tdx))
+ return -EINVAL;
+
+ err = tdh_mr_finalize(kvm_tdx->tdr_pa);
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MR_FINALIZE, err, NULL);
+ return -EIO;
+ }
+
+ /*
+ * Blindly do TDH_MEM_TRACK after finalizing the measurement to handle
+ * the case where SEPT entries were zapped/blocked, e.g. from failed
+ * NUMA balancing, after they were added to the TD via
+ * tdx_init_mem_region(). TDX module doesn't allow TDH_MEM_TRACK prior
+ * to TDH.MR.FINALIZE, and conversely requires TDH.MEM.TRACK for entries
+ * that were TDH.MEM.RANGE.BLOCK'd prior to TDH.MR.FINALIZE.
+ */
+ (void)tdh_mem_track(to_kvm_tdx(kvm)->tdr_pa);
+
+ kvm_tdx->finalized = true;
+ return 0;
+}
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_tdx_cmd tdx_cmd;
@@ -1314,6 +1342,9 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
case KVM_TDX_INIT_MEM_REGION:
r = tdx_init_mem_region(kvm, &tdx_cmd);
break;
+ case KVM_TDX_FINALIZE_VM:
+ r = tdx_td_finalizemr(kvm);
+ break;
default:
r = -EINVAL;
goto out;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index a7d4d8fe9ca8..e5a66160f0ad 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -568,6 +568,7 @@ enum kvm_tdx_cmd_id {
KVM_TDX_INIT_VM,
KVM_TDX_INIT_VCPU,
KVM_TDX_INIT_MEM_REGION,
+ KVM_TDX_FINALIZE_VM,
KVM_TDX_CMD_NR_MAX,
};
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TD vcpu
enter/exit.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index 46ae049b6b85..33e107bcb5cf 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -12,6 +12,7 @@ What qemu can do
- Qemu can create/destroy guest of TDX vm type.
- Qemu can create/destroy vcpu of TDX vm type.
- Qemu can populate initial guest memory image.
+- Qemu can finalize guest TD.
Patch Layer status
------------------
@@ -22,8 +23,8 @@ Patch Layer status
* TD VM creation/destruction: Applied
* TD vcpu creation/destruction: Applied
* TDX EPT violation: Applied
-* TD finalization: Applying
-* TD vcpu enter/exit: Not yet
+* TD finalization: Applied
+* TD vcpu enter/exit: Applying
* TD vcpu interrupts/exit/hypercall: Not yet
* KVM MMU GPA shared bits: Applied
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX requires TDX SEAMCALL to operate Secure EPT instead of direct memory
access and TDX SEAMCALL is heavy operation. Fast page fault on private GPA
doesn't make sense. Disallow fast page fault on private GPA.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/mmu/mmu.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 9bc640e0d821..5abf2c9c3402 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3289,8 +3289,16 @@ static int kvm_handle_noslot_fault(struct kvm_vcpu *vcpu,
return RET_PF_CONTINUE;
}
-static bool page_fault_can_be_fast(struct kvm_page_fault *fault)
+static bool page_fault_can_be_fast(struct kvm *kvm, struct kvm_page_fault *fault)
{
+ /*
+ * TDX private mapping doesn't support fast page fault because the EPT
+ * entry is read/written with TDX SEAMCALLs instead of direct memory
+ * access.
+ */
+ if (kvm_is_private_gpa(kvm, fault->addr))
+ return false;
+
/*
* Page faults with reserved bits set, i.e. faults on MMIO SPTEs, only
* reach the common page fault handler if the SPTE has an invalid MMIO
@@ -3400,7 +3408,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
u64 *sptep = NULL;
uint retry_count = 0;
- if (!page_fault_can_be_fast(fault))
+ if (!page_fault_can_be_fast(vcpu->kvm, fault))
return ret;
walk_shadow_page_lockless_begin(vcpu);
--
2.25.1
From: Sean Christopherson <[email protected]>
TDX requires special handling to support large private page. For
simplicity, only support 4K page for TD guest for now. Add per-VM maximum
page level support to support different maximum page sizes for TD guest and
conventional VMX guest.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Acked-by: Kai Huang <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/mmu/mmu.c | 1 +
arch/x86/kvm/mmu/mmu_internal.h | 2 +-
3 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 0fdd432e62e2..d441d281a6d6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1250,6 +1250,7 @@ struct kvm_arch {
unsigned long n_requested_mmu_pages;
unsigned long n_max_mmu_pages;
unsigned int indirect_shadow_pages;
+ int tdp_max_page_level;
u8 mmu_valid_gen;
struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES];
struct list_head active_mmu_pages;
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 5abf2c9c3402..5883ab95ff07 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6207,6 +6207,7 @@ int kvm_mmu_init_vm(struct kvm *kvm)
kvm->arch.split_desc_cache.kmem_cache = pte_list_desc_cache;
kvm->arch.split_desc_cache.gfp_zero = __GFP_ZERO;
+ kvm->arch.tdp_max_page_level = KVM_MAX_HUGEPAGE_LEVEL;
return 0;
}
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 37c47d44968e..b4fcf3eb6bd6 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -291,7 +291,7 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
.nx_huge_page_workaround_enabled =
is_nx_huge_page_enabled(vcpu->kvm),
- .max_level = KVM_MAX_HUGEPAGE_LEVEL,
+ .max_level = vcpu->kvm->arch.tdp_max_page_level,
.req_level = PG_LEVEL_4K,
.goal_level = PG_LEVEL_4K,
.is_private = kvm_mem_is_private(vcpu->kvm, cr2_or_gpa >> PAGE_SHIFT),
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX defines an API to run TDX vcpu with its own ABI. Define an assembly
helper function to run TDX vcpu to hide the special ABI so that C code can
call it with function call ABI.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/tdx.h | 3 +-
arch/x86/kvm/vmx/vmenter.S | 156 +++++++++++++++++++++++++++++++++++++
2 files changed, 158 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index bd09b03d7edd..d6631889624a 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -16,7 +16,8 @@
* Bits 47:40 == 0xFF indicate Reserved status code class that never used by
* TDX module.
*/
-#define TDX_ERROR _BITUL(63)
+#define TDX_ERROR_BIT 63
+#define TDX_ERROR _BITUL(TDX_ERROR_BIT)
#define TDX_SW_ERROR (TDX_ERROR | GENMASK_ULL(47, 40))
#define TDX_SEAMCALL_VMFAILINVALID (TDX_SW_ERROR | _UL(0xFFFF0000))
diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
index f550540ed54e..d9aa826c8f0e 100644
--- a/arch/x86/kvm/vmx/vmenter.S
+++ b/arch/x86/kvm/vmx/vmenter.S
@@ -6,6 +6,7 @@
#include <asm/nospec-branch.h>
#include <asm/percpu.h>
#include <asm/segment.h>
+#include <asm/tdx.h>
#include "kvm-asm-offsets.h"
#include "run_flags.h"
@@ -31,6 +32,12 @@
#define VCPU_R15 __VCPU_REGS_R15 * WORD_SIZE
#endif
+#ifdef CONFIG_INTEL_TDX_HOST
+#define TDH_VP_ENTER 0
+#define EXIT_REASON_TDCALL 77
+#define seamcall .byte 0x66,0x0f,0x01,0xcf
+#endif
+
.macro VMX_DO_EVENT_IRQOFF call_insn call_target
/*
* Unconditionally create a stack frame, getting the correct RSP on the
@@ -360,3 +367,152 @@ SYM_FUNC_END(vmread_error_trampoline)
SYM_FUNC_START(vmx_do_interrupt_irqoff)
VMX_DO_EVENT_IRQOFF CALL_NOSPEC _ASM_ARG1
SYM_FUNC_END(vmx_do_interrupt_irqoff)
+
+#ifdef CONFIG_INTEL_TDX_HOST
+
+.pushsection .noinstr.text, "ax"
+
+/**
+ * __tdx_vcpu_run - Call SEAMCALL(TDH_VP_ENTER) to run a TD vcpu
+ * @tdvpr: physical address of TDVPR
+ * @regs: void * (to registers of TDVCPU)
+ * @gpr_mask: non-zero if guest registers need to be loaded prior to TDH_VP_ENTER
+ *
+ * Returns:
+ * TD-Exit Reason
+ *
+ * Note: KVM doesn't support using XMM in its hypercalls, it's the HyperV
+ * code's responsibility to save/restore XMM registers on TDVMCALL.
+ */
+SYM_FUNC_START(__tdx_vcpu_run)
+ push %rbp
+ mov %rsp, %rbp
+
+ push %r15
+ push %r14
+ push %r13
+ push %r12
+ push %rbx
+
+ /* Save @regs, which is needed after TDH_VP_ENTER to capture output. */
+ push %rsi
+
+ /* Load @tdvpr to RCX */
+ mov %rdi, %rcx
+
+ /* No need to load guest GPRs if the last exit wasn't a TDVMCALL. */
+ test %dx, %dx
+ je 1f
+
+ /* Load @regs to RAX, which will be clobbered with $TDH_VP_ENTER anyways. */
+ mov %rsi, %rax
+
+ mov VCPU_RBX(%rax), %rbx
+ mov VCPU_RDX(%rax), %rdx
+ mov VCPU_RBP(%rax), %rbp
+ mov VCPU_RSI(%rax), %rsi
+ mov VCPU_RDI(%rax), %rdi
+
+ mov VCPU_R8 (%rax), %r8
+ mov VCPU_R9 (%rax), %r9
+ mov VCPU_R10(%rax), %r10
+ mov VCPU_R11(%rax), %r11
+ mov VCPU_R12(%rax), %r12
+ mov VCPU_R13(%rax), %r13
+ mov VCPU_R14(%rax), %r14
+ mov VCPU_R15(%rax), %r15
+
+ /* Load TDH_VP_ENTER to RAX. This kills the @regs pointer! */
+1: mov $TDH_VP_ENTER, %rax
+
+2: seamcall
+
+ /*
+ * Use same return value convention to tdxcall.S.
+ * TDX_SEAMCALL_VMFAILINVALID doesn't conflict with any TDX status code.
+ */
+ jnc 3f
+ mov $TDX_SEAMCALL_VMFAILINVALID, %rax
+ jmp 5f
+3:
+
+ /* Skip to the exit path if TDH_VP_ENTER failed. */
+ bt $TDX_ERROR_BIT, %rax
+ jc 5f
+
+ /* Temporarily save the TD-Exit reason. */
+ push %rax
+
+ /* check if TD-exit due to TDVMCALL */
+ cmp $EXIT_REASON_TDCALL, %ax
+
+ /* Reload @regs to RAX. */
+ mov 8(%rsp), %rax
+
+ /* Jump on non-TDVMCALL */
+ jne 4f
+
+ /* Save all output from SEAMCALL(TDH_VP_ENTER) */
+ mov %rbx, VCPU_RBX(%rax)
+ mov %rbp, VCPU_RBP(%rax)
+ mov %rsi, VCPU_RSI(%rax)
+ mov %rdi, VCPU_RDI(%rax)
+ mov %r10, VCPU_R10(%rax)
+ mov %r11, VCPU_R11(%rax)
+ mov %r12, VCPU_R12(%rax)
+ mov %r13, VCPU_R13(%rax)
+ mov %r14, VCPU_R14(%rax)
+ mov %r15, VCPU_R15(%rax)
+
+4: mov %rcx, VCPU_RCX(%rax)
+ mov %rdx, VCPU_RDX(%rax)
+ mov %r8, VCPU_R8 (%rax)
+ mov %r9, VCPU_R9 (%rax)
+
+ /*
+ * Clear all general purpose registers except RSP and RAX to prevent
+ * speculative use of the guest's values.
+ */
+ xor %rbx, %rbx
+ xor %rcx, %rcx
+ xor %rdx, %rdx
+ xor %rsi, %rsi
+ xor %rdi, %rdi
+ xor %rbp, %rbp
+ xor %r8, %r8
+ xor %r9, %r9
+ xor %r10, %r10
+ xor %r11, %r11
+ xor %r12, %r12
+ xor %r13, %r13
+ xor %r14, %r14
+ xor %r15, %r15
+
+ /* Restore the TD-Exit reason to RAX for return. */
+ pop %rax
+
+ /* "POP" @regs. */
+5: add $8, %rsp
+ pop %rbx
+ pop %r12
+ pop %r13
+ pop %r14
+ pop %r15
+
+ pop %rbp
+ RET
+
+6: cmpb $0, kvm_rebooting
+ je 1f
+ mov $TDX_SW_ERROR, %r12
+ orq %r12, %rax
+ jmp 5b
+1: ud2
+ /* Use FAULT version to know what fault happened. */
+ _ASM_EXTABLE_FAULT(2b, 6b)
+
+SYM_FUNC_END(__tdx_vcpu_run)
+
+.popsection
+
+#endif
--
2.25.1
From: Isaku Yamahata <[email protected]>
To support TDX, KVM is enhanced to operate with #VE. For TDX, KVM programs
to inject #VE conditionally and set #VE suppress bit in EPT entry. For VMX
case, #VE isn't used. If #VE happens for VMX, it's a bug. To be
defensive (test that VMX case isn't broken), introduce option
ept_violation_ve_test and when it's set, set error.
Suggested-by: Paolo Bonzini <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/vmx.h | 12 +++++++
arch/x86/kvm/vmx/vmcs.h | 5 +++
arch/x86/kvm/vmx/vmx.c | 69 +++++++++++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/vmx.h | 6 +++-
4 files changed, 90 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index cdbf12c1a83c..752d53652007 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -68,6 +68,7 @@
#define SECONDARY_EXEC_ENCLS_EXITING VMCS_CONTROL_BIT(ENCLS_EXITING)
#define SECONDARY_EXEC_RDSEED_EXITING VMCS_CONTROL_BIT(RDSEED_EXITING)
#define SECONDARY_EXEC_ENABLE_PML VMCS_CONTROL_BIT(PAGE_MOD_LOGGING)
+#define SECONDARY_EXEC_EPT_VIOLATION_VE VMCS_CONTROL_BIT(EPT_VIOLATION_VE)
#define SECONDARY_EXEC_PT_CONCEAL_VMX VMCS_CONTROL_BIT(PT_CONCEAL_VMX)
#define SECONDARY_EXEC_XSAVES VMCS_CONTROL_BIT(XSAVES)
#define SECONDARY_EXEC_MODE_BASED_EPT_EXEC VMCS_CONTROL_BIT(MODE_BASED_EPT_EXEC)
@@ -223,6 +224,8 @@ enum vmcs_field {
VMREAD_BITMAP_HIGH = 0x00002027,
VMWRITE_BITMAP = 0x00002028,
VMWRITE_BITMAP_HIGH = 0x00002029,
+ VE_INFORMATION_ADDRESS = 0x0000202A,
+ VE_INFORMATION_ADDRESS_HIGH = 0x0000202B,
XSS_EXIT_BITMAP = 0x0000202C,
XSS_EXIT_BITMAP_HIGH = 0x0000202D,
ENCLS_EXITING_BITMAP = 0x0000202E,
@@ -628,4 +631,13 @@ enum vmx_l1d_flush_state {
extern enum vmx_l1d_flush_state l1tf_vmx_mitigation;
+struct vmx_ve_information {
+ u32 exit_reason;
+ u32 delivery;
+ u64 exit_qualification;
+ u64 guest_linear_address;
+ u64 guest_physical_address;
+ u16 eptp_index;
+};
+
#endif
diff --git a/arch/x86/kvm/vmx/vmcs.h b/arch/x86/kvm/vmx/vmcs.h
index 7c1996b433e2..b25625314658 100644
--- a/arch/x86/kvm/vmx/vmcs.h
+++ b/arch/x86/kvm/vmx/vmcs.h
@@ -140,6 +140,11 @@ static inline bool is_nm_fault(u32 intr_info)
return is_exception_n(intr_info, NM_VECTOR);
}
+static inline bool is_ve_fault(u32 intr_info)
+{
+ return is_exception_n(intr_info, VE_VECTOR);
+}
+
/* Undocumented: icebp/int1 */
static inline bool is_icebp(u32 intr_info)
{
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index f9e9fd7fde2c..9a713538c2ad 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -127,6 +127,9 @@ module_param(error_on_inconsistent_vmcs_config, bool, 0444);
static bool __read_mostly dump_invalid_vmcs = 0;
module_param(dump_invalid_vmcs, bool, 0644);
+static bool __read_mostly ept_violation_ve_test;
+module_param(ept_violation_ve_test, bool, 0444);
+
#define MSR_BITMAP_MODE_X2APIC 1
#define MSR_BITMAP_MODE_X2APIC_APICV 2
@@ -844,6 +847,13 @@ void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu)
eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR) |
(1u << DB_VECTOR) | (1u << AC_VECTOR);
+ /*
+ * #VE isn't used for VMX, but for TDX. To test against unexpected
+ * change related to #VE for VMX, intercept unexpected #VE and warn on
+ * it.
+ */
+ if (ept_violation_ve_test)
+ eb |= 1u << VE_VECTOR;
/*
* Guest access to VMware backdoor ports could legitimately
* trigger #GP because of TSS I/O permission bitmap.
@@ -2613,6 +2623,9 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
&_cpu_based_2nd_exec_control))
return -EIO;
}
+ if (!ept_violation_ve_test)
+ _cpu_based_2nd_exec_control &= ~SECONDARY_EXEC_EPT_VIOLATION_VE;
+
#ifndef CONFIG_X86_64
if (!(_cpu_based_2nd_exec_control &
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES))
@@ -2637,6 +2650,7 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
return -EIO;
vmx_cap->ept = 0;
+ _cpu_based_2nd_exec_control &= ~SECONDARY_EXEC_EPT_VIOLATION_VE;
}
if (!(_cpu_based_2nd_exec_control & SECONDARY_EXEC_ENABLE_VPID) &&
vmx_cap->vpid) {
@@ -4573,6 +4587,7 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
exec_control &= ~SECONDARY_EXEC_ENABLE_VPID;
if (!enable_ept) {
exec_control &= ~SECONDARY_EXEC_ENABLE_EPT;
+ exec_control &= ~SECONDARY_EXEC_EPT_VIOLATION_VE;
enable_unrestricted_guest = 0;
}
if (!enable_unrestricted_guest)
@@ -4706,8 +4721,40 @@ static void init_vmcs(struct vcpu_vmx *vmx)
exec_controls_set(vmx, vmx_exec_control(vmx));
- if (cpu_has_secondary_exec_ctrls())
+ if (cpu_has_secondary_exec_ctrls()) {
secondary_exec_controls_set(vmx, vmx_secondary_exec_control(vmx));
+ if (secondary_exec_controls_get(vmx) &
+ SECONDARY_EXEC_EPT_VIOLATION_VE) {
+ if (!vmx->ve_info) {
+ /* ve_info must be page aligned. */
+ struct page *page;
+
+ BUILD_BUG_ON(sizeof(*vmx->ve_info) > PAGE_SIZE);
+ page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
+ if (page)
+ vmx->ve_info = page_to_virt(page);
+ }
+ if (vmx->ve_info) {
+ /*
+ * Allow #VE delivery. CPU sets this field to
+ * 0xFFFFFFFF on #VE delivery. Another #VE can
+ * occur only if software clears the field.
+ */
+ vmx->ve_info->delivery = 0;
+ vmcs_write64(VE_INFORMATION_ADDRESS,
+ __pa(vmx->ve_info));
+ } else {
+ /*
+ * Because SECONDARY_EXEC_EPT_VIOLATION_VE is
+ * used only when ept_violation_ve_test is true,
+ * it's okay to go with the bit disabled.
+ */
+ pr_err("Failed to allocate ve_info. disabling EPT_VIOLATION_VE.\n");
+ secondary_exec_controls_clearbit(vmx,
+ SECONDARY_EXEC_EPT_VIOLATION_VE);
+ }
+ }
+ }
if (cpu_has_tertiary_exec_ctrls())
tertiary_exec_controls_set(vmx, vmx_tertiary_exec_control(vmx));
@@ -5192,6 +5239,12 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
if (is_invalid_opcode(intr_info))
return handle_ud(vcpu);
+ /*
+ * #VE isn't supposed to happen. Although vcpu can send
+ */
+ if (KVM_BUG_ON(is_ve_fault(intr_info), vcpu->kvm))
+ return -EIO;
+
error_code = 0;
if (intr_info & INTR_INFO_DELIVER_CODE_MASK)
error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
@@ -6380,6 +6433,18 @@ void dump_vmcs(struct kvm_vcpu *vcpu)
if (secondary_exec_control & SECONDARY_EXEC_ENABLE_VPID)
pr_err("Virtual processor ID = 0x%04x\n",
vmcs_read16(VIRTUAL_PROCESSOR_ID));
+ if (secondary_exec_control & SECONDARY_EXEC_EPT_VIOLATION_VE) {
+ struct vmx_ve_information *ve_info;
+
+ pr_err("VE info address = 0x%016llx\n",
+ vmcs_read64(VE_INFORMATION_ADDRESS));
+ ve_info = __va(vmcs_read64(VE_INFORMATION_ADDRESS));
+ pr_err("ve_info: 0x%08x 0x%08x 0x%016llx 0x%016llx 0x%016llx 0x%04x\n",
+ ve_info->exit_reason, ve_info->delivery,
+ ve_info->exit_qualification,
+ ve_info->guest_linear_address,
+ ve_info->guest_physical_address, ve_info->eptp_index);
+ }
}
/*
@@ -7378,6 +7443,8 @@ void vmx_vcpu_free(struct kvm_vcpu *vcpu)
free_vpid(vmx->vpid);
nested_vmx_free_vcpu(vcpu);
free_loaded_vmcs(vmx->loaded_vmcs);
+ if (vmx->ve_info)
+ free_page((unsigned long)vmx->ve_info);
}
int vmx_vcpu_create(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 1d15c3c2751b..8a21988e091a 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -359,6 +359,9 @@ struct vcpu_vmx {
DECLARE_BITMAP(read, MAX_POSSIBLE_PASSTHROUGH_MSRS);
DECLARE_BITMAP(write, MAX_POSSIBLE_PASSTHROUGH_MSRS);
} shadow_msr_intercept;
+
+ /* ve_info must be page aligned. */
+ struct vmx_ve_information *ve_info;
};
struct kvm_vmx {
@@ -570,7 +573,8 @@ static inline u8 vmx_get_rvi(void)
SECONDARY_EXEC_ENABLE_VMFUNC | \
SECONDARY_EXEC_BUS_LOCK_DETECTION | \
SECONDARY_EXEC_NOTIFY_VM_EXITING | \
- SECONDARY_EXEC_ENCLS_EXITING)
+ SECONDARY_EXEC_ENCLS_EXITING | \
+ SECONDARY_EXEC_EPT_VIOLATION_VE)
#define KVM_REQUIRED_VMX_TERTIARY_VM_EXEC_CONTROL 0
#define KVM_OPTIONAL_VMX_TERTIARY_VM_EXEC_CONTROL \
--
2.25.1
From: Isaku Yamahata <[email protected]>
This patch implements running TDX vcpu. Once vcpu runs on the logical
processor (LP), the TDX vcpu is associated with it. When the TDX vcpu
moves to another LP, the TDX vcpu needs to flush its status on the LP.
When destroying TDX vcpu, it needs to complete flush and flush cpu memory
cache. Track which LP the TDX vcpu run and flush it as necessary.
Do nothing on sched_in event as TDX doesn't support pause loop.
TDX vcpu execution requires restoring PMU debug store after returning back
to KVM because the TDX module unconditionally resets the value. To reuse
the existing code, export perf_restore_debug_store.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 21 +++++++++++++++++++--
arch/x86/kvm/vmx/tdx.c | 32 ++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 33 +++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 2 ++
arch/x86/kvm/x86.c | 1 +
5 files changed, 87 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 55001b34e1f0..2fd6c954590d 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -170,6 +170,23 @@ static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vmx_vcpu_reset(vcpu, init_event);
}
+static int vt_vcpu_pre_run(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ /* Unconditionally continue to vcpu_run(). */
+ return 1;
+
+ return vmx_vcpu_pre_run(vcpu);
+}
+
+static fastpath_t vt_vcpu_run(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_vcpu_run(vcpu);
+
+ return vmx_vcpu_run(vcpu);
+}
+
static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu)) {
@@ -323,8 +340,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.flush_tlb_gva = vt_flush_tlb_gva,
.flush_tlb_guest = vt_flush_tlb_guest,
- .vcpu_pre_run = vmx_vcpu_pre_run,
- .vcpu_run = vmx_vcpu_run,
+ .vcpu_pre_run = vt_vcpu_pre_run,
+ .vcpu_run = vt_vcpu_run,
.handle_exit = vmx_handle_exit,
.skip_emulated_instruction = vmx_skip_emulated_instruction,
.update_emulated_instruction = vmx_update_emulated_instruction,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index d5a2f769a58d..28a19b14cbbc 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -11,6 +11,9 @@
#include "x86.h"
#include "mmu.h"
+#include <trace/events/kvm.h>
+#include "trace.h"
+
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -439,6 +442,35 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
*/
}
+u64 __tdx_vcpu_run(hpa_t tdvpr, void *regs, u32 regs_mask);
+
+static noinstr void tdx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
+ struct vcpu_tdx *tdx)
+{
+ guest_enter_irqoff();
+ tdx->exit_reason.full = __tdx_vcpu_run(tdx->tdvpr_pa, vcpu->arch.regs, 0);
+ guest_exit_irqoff();
+}
+
+fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ if (unlikely(vcpu->kvm->vm_bugged)) {
+ tdx->exit_reason.full = TDX_NON_RECOVERABLE_VCPU;
+ return EXIT_FASTPATH_NONE;
+ }
+
+ trace_kvm_entry(vcpu);
+
+ tdx_vcpu_enter_exit(vcpu, tdx);
+
+ vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET;
+ trace_kvm_exit(vcpu, KVM_ISA_VMX);
+
+ return EXIT_FASTPATH_NONE;
+}
+
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
{
td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 9d8445324841..af29e1d89657 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -25,12 +25,45 @@ struct kvm_tdx {
u64 tsc_offset;
};
+union tdx_exit_reason {
+ struct {
+ /* 31:0 mirror the VMX Exit Reason format */
+ u64 basic : 16;
+ u64 reserved16 : 1;
+ u64 reserved17 : 1;
+ u64 reserved18 : 1;
+ u64 reserved19 : 1;
+ u64 reserved20 : 1;
+ u64 reserved21 : 1;
+ u64 reserved22 : 1;
+ u64 reserved23 : 1;
+ u64 reserved24 : 1;
+ u64 reserved25 : 1;
+ u64 bus_lock_detected : 1;
+ u64 enclave_mode : 1;
+ u64 smi_pending_mtf : 1;
+ u64 smi_from_vmx_root : 1;
+ u64 reserved30 : 1;
+ u64 failed_vmentry : 1;
+
+ /* 63:32 are TDX specific */
+ u64 details_l1 : 8;
+ u64 class : 8;
+ u64 reserved61_48 : 14;
+ u64 non_recoverable : 1;
+ u64 error : 1;
+ };
+ u64 full;
+};
+
struct vcpu_tdx {
struct kvm_vcpu vcpu;
unsigned long tdvpr_pa;
unsigned long *tdvpx_pa;
+ union tdx_exit_reason exit_reason;
+
bool initialized;
/*
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index eba10dabc45f..c939a9d4d927 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -155,6 +155,7 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
+fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu);
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -181,6 +182,7 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP
static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
+static inline fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) { return EXIT_FASTPATH_NONE; }
static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6d7ca694e1c9..41af9a943d49 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -309,6 +309,7 @@ const struct kvm_stats_header kvm_vcpu_stats_header = {
};
u64 __read_mostly host_xcr0;
+EXPORT_SYMBOL_GPL(host_xcr0);
static struct kmem_cache *x86_emulator_cache;
--
2.25.1
From: Isaku Yamahata <[email protected]>
On entering/exiting TDX vcpu, Preserved or clobbered CPU state is different
from VMX case. Add TDX hooks to save/restore host/guest CPU state.
Save/restore kernel GS base MSR.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/main.c | 30 ++++++++++++++++++++++++++--
arch/x86/kvm/vmx/tdx.c | 41 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 4 ++++
arch/x86/kvm/vmx/x86_ops.h | 4 ++++
4 files changed, 77 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 2fd6c954590d..4a3b42ff9701 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -170,6 +170,32 @@ static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vmx_vcpu_reset(vcpu, init_event);
}
+static void vt_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
+{
+ /*
+ * All host state is saved/restored across SEAMCALL/SEAMRET, and the
+ * guest state of a TD is obviously off limits. Deferring MSRs and DRs
+ * is pointless because the TDX module needs to load *something* so as
+ * not to expose guest state.
+ */
+ if (is_td_vcpu(vcpu)) {
+ tdx_prepare_switch_to_guest(vcpu);
+ return;
+ }
+
+ vmx_prepare_switch_to_guest(vcpu);
+}
+
+static void vt_vcpu_put(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_vcpu_put(vcpu);
+ return;
+ }
+
+ vmx_vcpu_put(vcpu);
+}
+
static int vt_vcpu_pre_run(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu))
@@ -307,9 +333,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vcpu_free = vt_vcpu_free,
.vcpu_reset = vt_vcpu_reset,
- .prepare_switch_to_guest = vmx_prepare_switch_to_guest,
+ .prepare_switch_to_guest = vt_prepare_switch_to_guest,
.vcpu_load = vmx_vcpu_load,
- .vcpu_put = vmx_vcpu_put,
+ .vcpu_put = vt_vcpu_put,
.update_exception_bitmap = vmx_update_exception_bitmap,
.get_msr_feature = vmx_get_msr_feature,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 28a19b14cbbc..321635a94bd5 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/cpu.h>
+#include <linux/mmu_context.h>
#include <asm/tdx.h>
@@ -372,6 +373,8 @@ u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
int tdx_vcpu_create(struct kvm_vcpu *vcpu)
{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
/*
* On cpu creation, cpuid entry is blank. Forcibly enable
* X2APIC feature to allow X2APIC.
@@ -396,9 +399,45 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
vcpu->arch.guest_state_protected =
!(to_kvm_tdx(vcpu->kvm)->attributes & TDX_TD_ATTRIBUTE_DEBUG);
+ tdx->host_state_need_save = true;
+ tdx->host_state_need_restore = false;
+
return 0;
}
+void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ if (!tdx->host_state_need_save)
+ return;
+
+ if (likely(is_64bit_mm(current->mm)))
+ tdx->msr_host_kernel_gs_base = current->thread.gsbase;
+ else
+ tdx->msr_host_kernel_gs_base = read_msr(MSR_KERNEL_GS_BASE);
+
+ tdx->host_state_need_save = false;
+}
+
+static void tdx_prepare_switch_to_host(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ tdx->host_state_need_save = true;
+ if (!tdx->host_state_need_restore)
+ return;
+
+ wrmsrl(MSR_KERNEL_GS_BASE, tdx->msr_host_kernel_gs_base);
+ tdx->host_state_need_restore = false;
+}
+
+void tdx_vcpu_put(struct kvm_vcpu *vcpu)
+{
+ vmx_vcpu_pi_put(vcpu);
+ tdx_prepare_switch_to_host(vcpu);
+}
+
void tdx_vcpu_free(struct kvm_vcpu *vcpu)
{
struct vcpu_tdx *tdx = to_tdx(vcpu);
@@ -465,6 +504,8 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
tdx_vcpu_enter_exit(vcpu, tdx);
+ tdx->host_state_need_restore = true;
+
vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET;
trace_kvm_exit(vcpu, KVM_ISA_VMX);
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index af29e1d89657..cd50d366b7ee 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -66,6 +66,10 @@ struct vcpu_tdx {
bool initialized;
+ bool host_state_need_save;
+ bool host_state_need_restore;
+ u64 msr_host_kernel_gs_base;
+
/*
* Dummy to make pmu_intel not corrupt memory.
* TODO: Support PMU for TDX. Future work.
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index c939a9d4d927..ee697a3e9b14 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -156,6 +156,8 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu);
+void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
+void tdx_vcpu_put(struct kvm_vcpu *vcpu);
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -183,6 +185,8 @@ static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
static inline fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) { return EXIT_FASTPATH_NONE; }
+static inline void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) {}
+static inline void tdx_vcpu_put(struct kvm_vcpu *vcpu) {}
static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
2.25.1
From: Isaku Yamahata <[email protected]>
On exiting from the guest TD, xsave state is clobbered. Restore xsave
state on TD exit.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 321635a94bd5..21e6fb0eeeb5 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -2,6 +2,7 @@
#include <linux/cpu.h>
#include <linux/mmu_context.h>
+#include <asm/fpu/xcr.h>
#include <asm/tdx.h>
#include "capabilities.h"
@@ -481,6 +482,22 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
*/
}
+static void tdx_restore_host_xsave_state(struct kvm_vcpu *vcpu)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+
+ if (static_cpu_has(X86_FEATURE_XSAVE) &&
+ host_xcr0 != (kvm_tdx->xfam & kvm_caps.supported_xcr0))
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0);
+ if (static_cpu_has(X86_FEATURE_XSAVES) &&
+ /* PT can be exposed to TD guest regardless of KVM's XSS support */
+ host_xss != (kvm_tdx->xfam & (kvm_caps.supported_xss | XFEATURE_MASK_PT)))
+ wrmsrl(MSR_IA32_XSS, host_xss);
+ if (static_cpu_has(X86_FEATURE_PKU) &&
+ (kvm_tdx->xfam & XFEATURE_MASK_PKRU))
+ write_pkru(vcpu->arch.host_pkru);
+}
+
u64 __tdx_vcpu_run(hpa_t tdvpr, void *regs, u32 regs_mask);
static noinstr void tdx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
@@ -504,6 +521,7 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
tdx_vcpu_enter_exit(vcpu, tdx);
+ tdx_restore_host_xsave_state(vcpu);
tdx->host_state_need_restore = true;
vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Refactor tdp_mmu_alloc_sp() and tdp_mmu_init_sp and eliminate
tdp_mmu_init_child_sp(). Currently tdp_mmu_init_sp() (or
tdp_mmu_init_child_sp()) sets kvm_mmu_page.role after tdp_mmu_alloc_sp()
allocating struct kvm_mmu_page and its page table page. This patch makes
tdp_mmu_alloc_sp() initialize kvm_mmu_page.role instead of
tdp_mmu_init_sp().
To handle private page tables, argument of is_private needs to be passed
down. Given that already page level is passed down, it would be cumbersome
to add one more parameter about sp. Instead replace the level argument with
union kvm_mmu_page_role. Thus the number of argument won't be increased
and more info about sp can be passed down.
For private sp, secure page table will be also allocated in addition to
struct kvm_mmu_page and page table (spt member). The allocation functions
(tdp_mmu_alloc_sp() and __tdp_mmu_alloc_sp_for_split()) need to know if the
allocation is for the conventional page table or private page table. Pass
union kvm_mmu_role to those functions and initialize role member of struct
kvm_mmu_page.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/mmu/tdp_iter.h | 12 ++++++++++
arch/x86/kvm/mmu/tdp_mmu.c | 44 ++++++++++++++++---------------------
2 files changed, 31 insertions(+), 25 deletions(-)
diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h
index f0af385c56e0..9e56a5b1024c 100644
--- a/arch/x86/kvm/mmu/tdp_iter.h
+++ b/arch/x86/kvm/mmu/tdp_iter.h
@@ -115,4 +115,16 @@ void tdp_iter_start(struct tdp_iter *iter, struct kvm_mmu_page *root,
void tdp_iter_next(struct tdp_iter *iter);
void tdp_iter_restart(struct tdp_iter *iter);
+static inline union kvm_mmu_page_role tdp_iter_child_role(struct tdp_iter *iter)
+{
+ union kvm_mmu_page_role child_role;
+ struct kvm_mmu_page *parent_sp;
+
+ parent_sp = sptep_to_sp(rcu_dereference(iter->sptep));
+
+ child_role = parent_sp->role;
+ child_role.level--;
+ return child_role;
+}
+
#endif /* __KVM_X86_MMU_TDP_ITER_H */
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index b342ce3a6e83..920d5dc633b0 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -260,24 +260,30 @@ static struct kvm_mmu_page *tdp_mmu_next_root(struct kvm *kvm,
kvm_mmu_page_as_id(_root) != _as_id) { \
} else
-static struct kvm_mmu_page *tdp_mmu_alloc_sp(struct kvm_vcpu *vcpu)
+static struct kvm_mmu_page *tdp_mmu_alloc_sp(struct kvm_vcpu *vcpu,
+ union kvm_mmu_page_role role)
{
struct kvm_mmu_page *sp;
sp = kvm_mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache);
sp->spt = kvm_mmu_memory_cache_alloc(&vcpu->arch.mmu_shadow_page_cache);
+ sp->role = role;
return sp;
}
static void tdp_mmu_init_sp(struct kvm_mmu_page *sp, tdp_ptep_t sptep,
- gfn_t gfn, union kvm_mmu_page_role role)
+ gfn_t gfn)
{
INIT_LIST_HEAD(&sp->possible_nx_huge_page_link);
set_page_private(virt_to_page(sp->spt), (unsigned long)sp);
- sp->role = role;
+ /*
+ * role must be set before calling this function. At least role.level
+ * is not 0 (PG_LEVEL_NONE).
+ */
+ WARN_ON_ONCE(!sp->role.word);
sp->gfn = gfn;
sp->ptep = sptep;
sp->tdp_mmu_page = true;
@@ -285,20 +291,6 @@ static void tdp_mmu_init_sp(struct kvm_mmu_page *sp, tdp_ptep_t sptep,
trace_kvm_mmu_get_page(sp, true);
}
-static void tdp_mmu_init_child_sp(struct kvm_mmu_page *child_sp,
- struct tdp_iter *iter)
-{
- struct kvm_mmu_page *parent_sp;
- union kvm_mmu_page_role role;
-
- parent_sp = sptep_to_sp(rcu_dereference(iter->sptep));
-
- role = parent_sp->role;
- role.level--;
-
- tdp_mmu_init_sp(child_sp, iter->sptep, iter->gfn, role);
-}
-
hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu)
{
union kvm_mmu_page_role role = vcpu->arch.mmu->root_role;
@@ -317,8 +309,8 @@ hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu)
goto out;
}
- root = tdp_mmu_alloc_sp(vcpu);
- tdp_mmu_init_sp(root, NULL, 0, role);
+ root = tdp_mmu_alloc_sp(vcpu, role);
+ tdp_mmu_init_sp(root, NULL, 0);
refcount_set(&root->tdp_mmu_root_count, 1);
@@ -1183,8 +1175,8 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
* The SPTE is either non-present or points to a huge page that
* needs to be split.
*/
- sp = tdp_mmu_alloc_sp(vcpu);
- tdp_mmu_init_child_sp(sp, &iter);
+ sp = tdp_mmu_alloc_sp(vcpu, tdp_iter_child_role(&iter));
+ tdp_mmu_init_sp(sp, iter.sptep, iter.gfn);
sp->nx_huge_page_disallowed = fault->huge_page_disallowed;
@@ -1413,7 +1405,7 @@ bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm,
return spte_set;
}
-static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp)
+static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp, union kvm_mmu_page_role role)
{
struct kvm_mmu_page *sp;
@@ -1423,6 +1415,7 @@ static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp)
if (!sp)
return NULL;
+ sp->role = role;
sp->spt = (void *)__get_free_page(gfp);
if (!sp->spt) {
kmem_cache_free(mmu_page_header_cache, sp);
@@ -1436,6 +1429,7 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(struct kvm *kvm,
struct tdp_iter *iter,
bool shared)
{
+ union kvm_mmu_page_role role = tdp_iter_child_role(iter);
struct kvm_mmu_page *sp;
/*
@@ -1447,7 +1441,7 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(struct kvm *kvm,
* If this allocation fails we drop the lock and retry with reclaim
* allowed.
*/
- sp = __tdp_mmu_alloc_sp_for_split(GFP_NOWAIT | __GFP_ACCOUNT);
+ sp = __tdp_mmu_alloc_sp_for_split(GFP_NOWAIT | __GFP_ACCOUNT, role);
if (sp)
return sp;
@@ -1459,7 +1453,7 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(struct kvm *kvm,
write_unlock(&kvm->mmu_lock);
iter->yielded = true;
- sp = __tdp_mmu_alloc_sp_for_split(GFP_KERNEL_ACCOUNT);
+ sp = __tdp_mmu_alloc_sp_for_split(GFP_KERNEL_ACCOUNT, role);
if (shared)
read_lock(&kvm->mmu_lock);
@@ -1554,7 +1548,7 @@ static int tdp_mmu_split_huge_pages_root(struct kvm *kvm,
continue;
}
- tdp_mmu_init_child_sp(sp, &iter);
+ tdp_mmu_init_sp(sp, iter.sptep, iter.gfn);
if (tdp_mmu_split_huge_page(kvm, &iter, sp, shared))
goto retry;
--
2.25.1
From: Chao Gao <[email protected]>
Several MSRs are constant and only used in userspace(ring 3). But VMs may
have different values. KVM uses kvm_set_user_return_msr() to switch to
guest's values and leverages user return notifier to restore them when the
kernel is to return to userspace. To eliminate unnecessary wrmsr, KVM also
caches the value it wrote to an MSR last time.
TDX module unconditionally resets some of these MSRs to architectural INIT
state on TD exit. It makes the cached values in kvm_user_return_msrs are
inconsistent with values in hardware. This inconsistency needs to be
fixed. Otherwise, it may mislead kvm_on_user_return() to skip restoring
some MSRs to the host's values. kvm_set_user_return_msr() can help correct
this case, but it is not optimal as it always does a wrmsr. So, introduce
a variation of kvm_set_user_return_msr() to update cached values and skip
that wrmsr.
Signed-off-by: Chao Gao <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/x86.c | 25 ++++++++++++++++++++-----
2 files changed, 21 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7b735c3e7d8c..b462be0482a1 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2184,6 +2184,7 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
int kvm_add_user_return_msr(u32 msr);
int kvm_find_user_return_msr(u32 msr);
int kvm_set_user_return_msr(unsigned index, u64 val, u64 mask);
+void kvm_user_return_update_cache(unsigned int index, u64 val);
static inline bool kvm_is_supported_user_return_msr(u32 msr)
{
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 41af9a943d49..a086bb6e4460 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -434,6 +434,15 @@ static void kvm_user_return_msr_cpu_online(void)
}
}
+static void kvm_user_return_register_notifier(struct kvm_user_return_msrs *msrs)
+{
+ if (!msrs->registered) {
+ msrs->urn.on_user_return = kvm_on_user_return;
+ user_return_notifier_register(&msrs->urn);
+ msrs->registered = true;
+ }
+}
+
int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask)
{
unsigned int cpu = smp_processor_id();
@@ -448,15 +457,21 @@ int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask)
return 1;
msrs->values[slot].curr = value;
- if (!msrs->registered) {
- msrs->urn.on_user_return = kvm_on_user_return;
- user_return_notifier_register(&msrs->urn);
- msrs->registered = true;
- }
+ kvm_user_return_register_notifier(msrs);
return 0;
}
EXPORT_SYMBOL_GPL(kvm_set_user_return_msr);
+/* Update the cache, "curr", and register the notifier */
+void kvm_user_return_update_cache(unsigned int slot, u64 value)
+{
+ struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs);
+
+ msrs->values[slot].curr = value;
+ kvm_user_return_register_notifier(msrs);
+}
+EXPORT_SYMBOL_GPL(kvm_user_return_update_cache);
+
static void drop_user_return_notifiers(void)
{
unsigned int cpu = smp_processor_id();
--
2.25.1
From: Isaku Yamahata <[email protected]>
Several user ret MSRs are clobbered on TD exit. Restore those values on
TD exit and before returning to ring 3.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 43 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 21e6fb0eeeb5..9bff4513c8ab 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -482,6 +482,28 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
*/
}
+struct tdx_uret_msr {
+ u32 msr;
+ unsigned int slot;
+ u64 defval;
+};
+
+static struct tdx_uret_msr tdx_uret_msrs[] = {
+ {.msr = MSR_SYSCALL_MASK,},
+ {.msr = MSR_STAR,},
+ {.msr = MSR_LSTAR,},
+ {.msr = MSR_TSC_AUX,},
+};
+
+static void tdx_user_return_update_cache(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tdx_uret_msrs); i++)
+ kvm_user_return_update_cache(tdx_uret_msrs[i].slot,
+ tdx_uret_msrs[i].defval);
+}
+
static void tdx_restore_host_xsave_state(struct kvm_vcpu *vcpu)
{
struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
@@ -521,6 +543,7 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
tdx_vcpu_enter_exit(vcpu, tdx);
+ tdx_user_return_update_cache();
tdx_restore_host_xsave_state(vcpu);
tdx->host_state_need_restore = true;
@@ -1630,6 +1653,26 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
return -EINVAL;
}
+ for (i = 0; i < ARRAY_SIZE(tdx_uret_msrs); i++) {
+ /*
+ * Here it checks if MSRs (tdx_uret_msrs) can be saved/restored
+ * before returning to user space.
+ *
+ * this_cpu_ptr(user_return_msrs)->registered isn't checked
+ * because the registration is done at vcpu runtime by
+ * kvm_set_user_return_msr().
+ * Here is setting up cpu feature before running vcpu,
+ * registered is already false.
+ */
+ tdx_uret_msrs[i].slot = kvm_find_user_return_msr(tdx_uret_msrs[i].msr);
+ if (tdx_uret_msrs[i].slot == -1) {
+ /* If any MSR isn't supported, it is a KVM bug */
+ pr_err("MSR %x isn't included by kvm_find_user_return_msr\n",
+ tdx_uret_msrs[i].msr);
+ return -EIO;
+ }
+ }
+
max_pkgs = topology_max_packages();
tdx_mng_key_config_lock = kcalloc(max_pkgs, sizeof(*tdx_mng_key_config_lock),
GFP_KERNEL);
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the start of patch series of TD vcpu
exits, interrupts, and hypercalls.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/intel-tdx-layer-status.rst | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
index 33e107bcb5cf..7a16fa284b6f 100644
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ b/Documentation/virt/kvm/intel-tdx-layer-status.rst
@@ -13,6 +13,7 @@ What qemu can do
- Qemu can create/destroy vcpu of TDX vm type.
- Qemu can populate initial guest memory image.
- Qemu can finalize guest TD.
+- Qemu can start to run vcpu. But vcpu can not make progress yet.
Patch Layer status
------------------
@@ -24,7 +25,7 @@ Patch Layer status
* TD vcpu creation/destruction: Applied
* TDX EPT violation: Applied
* TD finalization: Applied
-* TD vcpu enter/exit: Applying
+* TD vcpu enter/exit: Applied
* TD vcpu interrupts/exit/hypercall: Not yet
* KVM MMU GPA shared bits: Applied
--
2.25.1
From: Isaku Yamahata <[email protected]>
This corresponds to VMX __vmx_complete_interrupts(). Because TDX
virtualize vAPIC, KVM only needs to care NMI injection.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 10 ++++++++++
arch/x86/kvm/vmx/tdx.h | 2 ++
2 files changed, 12 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 9bff4513c8ab..e1d159ca3e4b 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -482,6 +482,14 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
*/
}
+static void tdx_complete_interrupts(struct kvm_vcpu *vcpu)
+{
+ /* Avoid costly SEAMCALL if no nmi was injected */
+ if (vcpu->arch.nmi_injected)
+ vcpu->arch.nmi_injected = td_management_read8(to_tdx(vcpu),
+ TD_VCPU_PEND_NMI);
+}
+
struct tdx_uret_msr {
u32 msr;
unsigned int slot;
@@ -550,6 +558,8 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET;
trace_kvm_exit(vcpu, KVM_ISA_VMX);
+ tdx_complete_interrupts(vcpu);
+
return EXIT_FASTPATH_NONE;
}
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index cd50d366b7ee..e66e5762ae04 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -192,6 +192,8 @@ TDX_BUILD_TDVPS_ACCESSORS(16, VMCS, vmcs);
TDX_BUILD_TDVPS_ACCESSORS(32, VMCS, vmcs);
TDX_BUILD_TDVPS_ACCESSORS(64, VMCS, vmcs);
+TDX_BUILD_TDVPS_ACCESSORS(8, MANAGEMENT, management);
+
static __always_inline u64 td_tdcs_exec_read64(struct kvm_tdx *kvm_tdx, u32 field)
{
struct tdx_module_output out;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because debug store is clobbered, restore it on TD exit.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/events/intel/ds.c | 1 +
arch/x86/kvm/vmx/tdx.c | 1 +
2 files changed, 2 insertions(+)
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index a2e566e53076..d454ed9b1556 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -2415,3 +2415,4 @@ void perf_restore_debug_store(void)
wrmsrl(MSR_IA32_DS_AREA, (unsigned long)ds);
}
+EXPORT_SYMBOL_GPL(perf_restore_debug_store);
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index e1d159ca3e4b..99d700bb1baa 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -552,6 +552,7 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
tdx_vcpu_enter_exit(vcpu, tdx);
tdx_user_return_update_cache();
+ perf_restore_debug_store();
tdx_restore_host_xsave_state(vcpu);
tdx->host_state_need_restore = true;
--
2.25.1
From: Isaku Yamahata <[email protected]>
For vcpu migration, in the case of VMX, VMCS is flushed on the source pcpu,
and load it on the target pcpu. There are corresponding TDX SEAMCALL APIs,
call them on vcpu migration. The logic is mostly same as VMX except the
TDX SEAMCALLs are used.
When shutting down the machine, (VMX or TDX) vcpus needs to be shutdown on
each pcpu. Do the similar for TDX with TDX SEAMCALL APIs.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 38 ++++++++-
arch/x86/kvm/vmx/tdx.c | 167 +++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.h | 2 +
arch/x86/kvm/vmx/x86_ops.h | 6 ++
4 files changed, 210 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 4a3b42ff9701..5d7164557c6c 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -45,6 +45,14 @@ static int vt_max_vcpus(struct kvm *kvm)
}
static int vt_tlb_remote_flush(struct kvm *kvm);
+static void vt_hardware_disable(void)
+{
+ /* Note, TDX *and* VMX need to be disabled if TDX is enabled. */
+ if (enable_tdx)
+ tdx_hardware_disable();
+ vmx_hardware_disable();
+}
+
static __init int vt_hardware_setup(void)
{
int ret;
@@ -213,6 +221,16 @@ static fastpath_t vt_vcpu_run(struct kvm_vcpu *vcpu)
return vmx_vcpu_run(vcpu);
}
+static void vt_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_vcpu_load(vcpu, cpu);
+ return;
+ }
+
+ vmx_vcpu_load(vcpu, cpu);
+}
+
static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu)) {
@@ -272,6 +290,14 @@ static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
}
+static void vt_sched_in(struct kvm_vcpu *vcpu, int cpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_sched_in(vcpu, cpu);
+}
+
static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
if (is_td_vcpu(vcpu))
@@ -316,7 +342,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.offline_cpu = tdx_offline_cpu,
.hardware_enable = vt_hardware_enable,
- .hardware_disable = vmx_hardware_disable,
+ .hardware_disable = vt_hardware_disable,
.has_emulated_msr = vmx_has_emulated_msr,
.is_vm_type_supported = vt_is_vm_type_supported,
@@ -334,7 +360,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vcpu_reset = vt_vcpu_reset,
.prepare_switch_to_guest = vt_prepare_switch_to_guest,
- .vcpu_load = vmx_vcpu_load,
+ .vcpu_load = vt_vcpu_load,
.vcpu_put = vt_vcpu_put,
.update_exception_bitmap = vmx_update_exception_bitmap,
@@ -420,7 +446,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.request_immediate_exit = vmx_request_immediate_exit,
- .sched_in = vmx_sched_in,
+ .sched_in = vt_sched_in,
.cpu_dirty_log_size = PML_ENTITY_NUM,
.update_cpu_dirty_logging = vmx_update_cpu_dirty_logging,
@@ -488,6 +514,10 @@ static int __init vt_init(void)
if (r)
goto err_vmx_init;
+ r = tdx_init();
+ if (r)
+ goto err_tdx_init;
+
/*
* Common KVM initialization _must_ come last, after this, /dev/kvm is
* exposed to userspace!
@@ -510,6 +540,8 @@ static int __init vt_init(void)
return 0;
err_kvm_init:
+ /* tdx_exit() is not defined. */
+err_tdx_init:
vmx_exit();
err_vmx_init:
kvm_x86_vendor_exit();
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 99d700bb1baa..ba9669d56ea3 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -74,6 +74,14 @@ static DEFINE_MUTEX(tdx_lock);
static struct mutex *tdx_mng_key_config_lock;
static atomic_t nr_configured_hkid;
+/*
+ * A per-CPU list of TD vCPUs associated with a given CPU. Used when a CPU
+ * is brought down to invoke TDH_VP_FLUSH on the approapriate TD vCPUS.
+ * Protected by interrupt mask. This list is manipulated in process context
+ * of vcpu and IPI callback. See tdx_flush_vp_on_cpu().
+ */
+static DEFINE_PER_CPU(struct list_head, associated_tdvcpus);
+
static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
{
return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
@@ -105,11 +113,51 @@ static inline bool is_td_finalized(struct kvm_tdx *kvm_tdx)
return kvm_tdx->finalized;
}
+static inline void tdx_disassociate_vp(struct kvm_vcpu *vcpu)
+{
+ list_del(&to_tdx(vcpu)->cpu_list);
+
+ /*
+ * Ensure tdx->cpu_list is updated is before setting vcpu->cpu to -1,
+ * otherwise, a different CPU can see vcpu->cpu = -1 and add the vCPU
+ * to its list before its deleted from this CPUs list.
+ */
+ smp_wmb();
+
+ vcpu->cpu = -1;
+}
+
+static void tdx_disassociate_vp_arg(void *vcpu)
+{
+ tdx_disassociate_vp(vcpu);
+}
+
+static void tdx_disassociate_vp_on_cpu(struct kvm_vcpu *vcpu)
+{
+ int cpu = vcpu->cpu;
+
+ if (unlikely(cpu == -1))
+ return;
+
+ smp_call_function_single(cpu, tdx_disassociate_vp_arg, vcpu, 1);
+}
+
int tdx_hardware_enable(void)
{
return tdx_cpu_enable();
}
+void tdx_hardware_disable(void)
+{
+ int cpu = raw_smp_processor_id();
+ struct list_head *tdvcpus = &per_cpu(associated_tdvcpus, cpu);
+ struct vcpu_tdx *tdx, *tmp;
+
+ /* Safe variant needed as tdx_disassociate_vp() deletes the entry. */
+ list_for_each_entry_safe(tdx, tmp, tdvcpus, cpu_list)
+ tdx_disassociate_vp(&tdx->vcpu);
+}
+
static void tdx_clear_page(unsigned long page_pa)
{
const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
@@ -199,6 +247,68 @@ static void tdx_reclaim_td_page(unsigned long td_page_pa)
free_page((unsigned long)__va(td_page_pa));
}
+struct tdx_flush_vp_arg {
+ struct kvm_vcpu *vcpu;
+ u64 err;
+};
+
+static void tdx_flush_vp(void *arg_)
+{
+ struct tdx_flush_vp_arg *arg = arg_;
+ struct kvm_vcpu *vcpu = arg->vcpu;
+ u64 err;
+
+ arg->err = 0;
+ lockdep_assert_irqs_disabled();
+
+ /* Task migration can race with CPU offlining. */
+ if (vcpu->cpu != raw_smp_processor_id())
+ return;
+
+ /*
+ * No need to do TDH_VP_FLUSH if the vCPU hasn't been initialized. The
+ * list tracking still needs to be updated so that it's correct if/when
+ * the vCPU does get initialized.
+ */
+ if (is_td_vcpu_created(to_tdx(vcpu))) {
+ /*
+ * No need to retry. TDX Resources needed for TDH.VP.FLUSH are,
+ * TDVPR as exclusive, TDR as shared, and TDCS as shared. This
+ * vp flush function is called when destructing vcpu/TD or vcpu
+ * migration. No other thread uses TDVPR in those cases.
+ */
+ err = tdh_vp_flush(to_tdx(vcpu)->tdvpr_pa);
+ if (unlikely(err && err != TDX_VCPU_NOT_ASSOCIATED)) {
+ /*
+ * This function is called in IPI context. Do not use
+ * printk to avoid console semaphore.
+ * The caller prints out the error message, instead.
+ */
+ if (err)
+ arg->err = err;
+ }
+ }
+
+ tdx_disassociate_vp(vcpu);
+}
+
+static void tdx_flush_vp_on_cpu(struct kvm_vcpu *vcpu)
+{
+ struct tdx_flush_vp_arg arg = {
+ .vcpu = vcpu,
+ };
+ int cpu = vcpu->cpu;
+
+ if (unlikely(cpu == -1))
+ return;
+
+ smp_call_function_single(cpu, tdx_flush_vp, &arg, 1);
+ if (WARN_ON_ONCE(arg.err)) {
+ pr_err("cpu: %d ", cpu);
+ pr_tdx_error(TDH_VP_FLUSH, arg.err, NULL);
+ }
+}
+
static int tdx_do_tdh_phymem_cache_wb(void *param)
{
u64 err = 0;
@@ -223,6 +333,8 @@ void tdx_mmu_release_hkid(struct kvm *kvm)
struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
cpumask_var_t packages;
bool cpumask_allocated;
+ struct kvm_vcpu *vcpu;
+ unsigned long j;
u64 err;
int ret;
int i;
@@ -233,6 +345,19 @@ void tdx_mmu_release_hkid(struct kvm *kvm)
if (!is_td_created(kvm_tdx))
goto free_hkid;
+ kvm_for_each_vcpu(j, vcpu, kvm)
+ tdx_flush_vp_on_cpu(vcpu);
+
+ mutex_lock(&tdx_lock);
+ err = tdh_mng_vpflushdone(kvm_tdx->tdr_pa);
+ mutex_unlock(&tdx_lock);
+ if (WARN_ON_ONCE(err)) {
+ pr_tdx_error(TDH_MNG_VPFLUSHDONE, err, NULL);
+ pr_err("tdh_mng_vpflushdone failed. HKID %d is leaked.\n",
+ kvm_tdx->hkid);
+ return;
+ }
+
cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
cpus_read_lock();
for_each_online_cpu(i) {
@@ -406,6 +531,26 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
return 0;
}
+void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ if (vcpu->cpu == cpu)
+ return;
+
+ tdx_flush_vp_on_cpu(vcpu);
+
+ local_irq_disable();
+ /*
+ * Pairs with the smp_wmb() in tdx_disassociate_vp() to ensure
+ * vcpu->cpu is read before tdx->cpu_list.
+ */
+ smp_rmb();
+
+ list_add(&tdx->cpu_list, &per_cpu(associated_tdvcpus, cpu));
+ local_irq_enable();
+}
+
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
{
struct vcpu_tdx *tdx = to_tdx(vcpu);
@@ -455,6 +600,19 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu)
return;
}
+ /*
+ * kvm_free_vcpus()
+ * -> kvm_unload_vcpu_mmu()
+ *
+ * does vcpu_load() for every vcpu after they already disassociated
+ * from the per cpu list when tdx_vm_teardown(). So we need to
+ * disassociate them again, otherwise the freed vcpu data will be
+ * accessed when do list_{del,add}() on associated_tdvcpus list
+ * later.
+ */
+ tdx_disassociate_vp_on_cpu(vcpu);
+ WARN_ON_ONCE(vcpu->cpu != -1);
+
if (tdx->tdvpx_pa) {
for (i = 0; i < tdx_info.nr_tdvpx_pages; i++)
tdx_reclaim_td_page(tdx->tdvpx_pa[i]);
@@ -1772,3 +1930,12 @@ int tdx_offline_cpu(void)
"Delete all TDs in order to offline all CPUs of a package.\n");
return ret;
}
+
+int __init tdx_init(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ INIT_LIST_HEAD(&per_cpu(associated_tdvcpus, cpu));
+ return 0;
+}
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index e66e5762ae04..1595c124899d 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -62,6 +62,8 @@ struct vcpu_tdx {
unsigned long tdvpr_pa;
unsigned long *tdvpx_pa;
+ struct list_head cpu_list;
+
union tdx_exit_reason exit_reason;
bool initialized;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index ee697a3e9b14..2dace209e7d3 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -138,9 +138,11 @@ void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu);
void vmx_setup_mce(struct kvm_vcpu *vcpu);
#ifdef CONFIG_INTEL_TDX_HOST
+int __init tdx_init(void);
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
void tdx_hardware_unsetup(void);
int tdx_hardware_enable(void);
+void tdx_hardware_disable(void);
bool tdx_is_vm_type_supported(unsigned long type);
int tdx_dev_ioctl(void __user *argp);
int tdx_offline_cpu(void);
@@ -158,6 +160,7 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu);
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
void tdx_vcpu_put(struct kvm_vcpu *vcpu);
+void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -166,9 +169,11 @@ void tdx_flush_tlb(struct kvm_vcpu *vcpu);
int tdx_sept_tlb_remote_flush(struct kvm *kvm);
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
#else
+static inline int tdx_init(void) { return 0; };
static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
static inline void tdx_hardware_unsetup(void) {}
static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
+static inline void tdx_hardware_disable(void) {}
static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
static inline int tdx_offline_cpu(void) { return 0; }
@@ -187,6 +192,7 @@ static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
static inline fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) { return EXIT_FASTPATH_NONE; }
static inline void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_put(struct kvm_vcpu *vcpu) {}
+static inline void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) {}
static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
2.25.1
From: Isaku Yamahata <[email protected]>
Add a flag, KVM_DEBUGREG_AUTO_SWITCHED_GUEST, to skip saving/restoring DRs
irrespective of any other flags. TDX-SEAM unconditionally saves and
restores guest DRs and reset to architectural INIT state on TD exit.
So, KVM needs to save host DRs before TD enter without restoring guest DRs
and restore host DRs after TD exit.
Opportunistically convert the KVM_DEBUGREG_* definitions to use BIT().
Reported-by: Xiaoyao Li <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Co-developed-by: Chao Gao <[email protected]>
Signed-off-by: Chao Gao <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 10 ++++++++--
arch/x86/kvm/vmx/tdx.c | 1 +
arch/x86/kvm/x86.c | 11 ++++++++---
3 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b462be0482a1..3e00fd1eb136 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -603,8 +603,14 @@ struct kvm_pmu {
struct kvm_pmu_ops;
enum {
- KVM_DEBUGREG_BP_ENABLED = 1,
- KVM_DEBUGREG_WONT_EXIT = 2,
+ KVM_DEBUGREG_BP_ENABLED = BIT(0),
+ KVM_DEBUGREG_WONT_EXIT = BIT(1),
+ /*
+ * Guest debug registers (DR0-3 and DR6) are saved/restored by hardware
+ * on exit from or enter to guest. KVM needn't switch them. Because DR7
+ * is cleared on exit from guest, DR7 need to be saved/restored.
+ */
+ KVM_DEBUGREG_AUTO_SWITCH = BIT(2),
};
struct kvm_mtrr_range {
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index ba9669d56ea3..e354fd08cbaf 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -517,6 +517,7 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
vcpu->arch.efer = EFER_SCE | EFER_LME | EFER_LMA | EFER_NX;
+ vcpu->arch.switch_db_regs = KVM_DEBUGREG_AUTO_SWITCH;
vcpu->arch.cr0_guest_owned_bits = -1ul;
vcpu->arch.cr4_guest_owned_bits = -1ul;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a086bb6e4460..84e4b00cc21a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10674,7 +10674,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
if (vcpu->arch.guest_fpu.xfd_err)
wrmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
- if (unlikely(vcpu->arch.switch_db_regs)) {
+ if (unlikely(vcpu->arch.switch_db_regs & ~KVM_DEBUGREG_AUTO_SWITCH)) {
set_debugreg(0, 7);
set_debugreg(vcpu->arch.eff_db[0], 0);
set_debugreg(vcpu->arch.eff_db[1], 1);
@@ -10717,6 +10717,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
*/
if (unlikely(vcpu->arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)) {
WARN_ON(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP);
+ WARN_ON(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH);
static_call(kvm_x86_sync_dirty_debug_regs)(vcpu);
kvm_update_dr0123(vcpu);
kvm_update_dr7(vcpu);
@@ -10729,8 +10730,12 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
* care about the messed up debug address registers. But if
* we have some of them active, restore the old state.
*/
- if (hw_breakpoint_active())
- hw_breakpoint_restore();
+ if (hw_breakpoint_active()) {
+ if (!(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH))
+ hw_breakpoint_restore();
+ else
+ set_debugreg(__this_cpu_read(cpu_dr7), 7);
+ }
vcpu->arch.last_vmentry_cpu = vcpu->cpu;
vcpu->arch.last_guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX doesn't support system-management mode (SMM) and system-management
interrupt (SMI) in guest TDs. Because guest state (vcpu state, memory
state) is protected, it must go through the TDX module APIs to change guest
state, injecting SMI and changing vcpu mode into SMM. The TDX module
doesn't provide a way for VMM to inject SMI into guest TD and a way for VMM
to switch guest vcpu mode into SMM.
We have two options in KVM when handling SMM or SMI in the guest TD or the
device model (e.g. QEMU): 1) silently ignore the request or 2) return a
meaningful error.
For simplicity, we implemented the option 1).
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/smm.h | 7 +++++-
arch/x86/kvm/vmx/main.c | 45 ++++++++++++++++++++++++++++++++++----
arch/x86/kvm/vmx/tdx.c | 29 ++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 12 ++++++++++
4 files changed, 88 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
index a1cf2ac5bd78..bc77902f5c18 100644
--- a/arch/x86/kvm/smm.h
+++ b/arch/x86/kvm/smm.h
@@ -142,7 +142,12 @@ union kvm_smram {
static inline int kvm_inject_smi(struct kvm_vcpu *vcpu)
{
- kvm_make_request(KVM_REQ_SMI, vcpu);
+ /*
+ * If SMM isn't supported (e.g. TDX), silently discard SMI request.
+ * Assume that SMM supported = MSR_IA32_SMBASE supported.
+ */
+ if (static_call(kvm_x86_has_emulated_msr)(vcpu->kvm, MSR_IA32_SMBASE))
+ kvm_make_request(KVM_REQ_SMI, vcpu);
return 0;
}
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 9901d4400b7b..a01efaa10bbc 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -295,6 +295,43 @@ static void vt_msr_filter_changed(struct kvm_vcpu *vcpu)
vmx_msr_filter_changed(vcpu);
}
+#ifdef CONFIG_KVM_SMM
+static int vt_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_smi_allowed(vcpu, for_injection);
+
+ return vmx_smi_allowed(vcpu, for_injection);
+}
+
+static int vt_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram)
+{
+ if (unlikely(is_td_vcpu(vcpu)))
+ return tdx_enter_smm(vcpu, smram);
+
+ return vmx_enter_smm(vcpu, smram);
+}
+
+static int vt_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram)
+{
+ if (unlikely(is_td_vcpu(vcpu)))
+ return tdx_leave_smm(vcpu, smram);
+
+ return vmx_leave_smm(vcpu, smram);
+}
+
+static void vt_enable_smi_window(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_enable_smi_window(vcpu);
+ return;
+ }
+
+ /* RSM will cause a vmexit anyway. */
+ vmx_enable_smi_window(vcpu);
+}
+#endif
+
static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
struct pi_desc *pi = vcpu_to_pi_desc(vcpu);
@@ -680,10 +717,10 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.setup_mce = vmx_setup_mce,
#ifdef CONFIG_KVM_SMM
- .smi_allowed = vmx_smi_allowed,
- .enter_smm = vmx_enter_smm,
- .leave_smm = vmx_leave_smm,
- .enable_smi_window = vmx_enable_smi_window,
+ .smi_allowed = vt_smi_allowed,
+ .enter_smm = vt_enter_smm,
+ .leave_smm = vt_leave_smm,
+ .enable_smi_window = vt_enable_smi_window,
#endif
.can_emulate_instruction = vmx_can_emulate_instruction,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 10bbac208a9c..5c6f8b73b820 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1829,6 +1829,35 @@ int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
return 1;
}
+#ifdef CONFIG_KVM_SMM
+int tdx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+{
+ /* SMI isn't supported for TDX. */
+ WARN_ON_ONCE(1);
+ return false;
+}
+
+int tdx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram)
+{
+ /* smi_allowed() is always false for TDX as above. */
+ WARN_ON_ONCE(1);
+ return 0;
+}
+
+int tdx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram)
+{
+ WARN_ON_ONCE(1);
+ return 0;
+}
+
+void tdx_enable_smi_window(struct kvm_vcpu *vcpu)
+{
+ /* SMI isn't supported for TDX. Silently discard SMI request. */
+ WARN_ON_ONCE(1);
+ vcpu->arch.smi_pending = false;
+}
+#endif
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 4e0befb9d530..59d74f4a4b63 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -227,4 +227,16 @@ static inline int tdx_sept_tlb_remote_flush(struct kvm *kvm) { return 0; }
static inline void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level) {}
#endif
+#if defined(CONFIG_INTEL_TDX_HOST) && defined(CONFIG_KVM_SMM)
+int tdx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection);
+int tdx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram);
+int tdx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram);
+void tdx_enable_smi_window(struct kvm_vcpu *vcpu);
+#else
+static inline int tdx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection) { return false; }
+static inline int tdx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram) { return 0; }
+static inline int tdx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram) { return 0; }
+static inline void tdx_enable_smi_window(struct kvm_vcpu *vcpu) {}
+#endif
+
#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
From: Isaku Yamahata <[email protected]>
As TDX will use posted_interrupt.c, the use of struct vcpu_vmx is a
blocker. Because the members of struct pi_desc pi_desc and struct
list_head pi_wakeup_list are only used in posted_interrupt.c, introduce
common structure, struct vcpu_pi, make vcpu_vmx and vcpu_tdx has same
layout in the top of structure.
To minimize the diff size, avoid code conversion like,
vmx->pi_desc => vmx->common->pi_desc. Instead add compile time check
if the layout is expected.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/posted_intr.c | 41 ++++++++++++++++++++++++++--------
arch/x86/kvm/vmx/posted_intr.h | 11 +++++++++
arch/x86/kvm/vmx/tdx.c | 1 +
arch/x86/kvm/vmx/tdx.h | 8 +++++++
arch/x86/kvm/vmx/vmx.h | 14 +++++++-----
5 files changed, 60 insertions(+), 15 deletions(-)
diff --git a/arch/x86/kvm/vmx/posted_intr.c b/arch/x86/kvm/vmx/posted_intr.c
index 94c38bea60e7..92de016852ca 100644
--- a/arch/x86/kvm/vmx/posted_intr.c
+++ b/arch/x86/kvm/vmx/posted_intr.c
@@ -11,6 +11,7 @@
#include "posted_intr.h"
#include "trace.h"
#include "vmx.h"
+#include "tdx.h"
/*
* Maintain a per-CPU list of vCPUs that need to be awakened by wakeup_handler()
@@ -31,9 +32,29 @@ static DEFINE_PER_CPU(struct list_head, wakeup_vcpus_on_cpu);
*/
static DEFINE_PER_CPU(raw_spinlock_t, wakeup_vcpus_on_cpu_lock);
+/*
+ * The layout of the head of struct vcpu_vmx and struct vcpu_tdx must match with
+ * struct vcpu_pi.
+ */
+static_assert(offsetof(struct vcpu_pi, pi_desc) ==
+ offsetof(struct vcpu_vmx, pi_desc));
+static_assert(offsetof(struct vcpu_pi, pi_wakeup_list) ==
+ offsetof(struct vcpu_vmx, pi_wakeup_list));
+#ifdef CONFIG_INTEL_TDX_HOST
+static_assert(offsetof(struct vcpu_pi, pi_desc) ==
+ offsetof(struct vcpu_tdx, pi_desc));
+static_assert(offsetof(struct vcpu_pi, pi_wakeup_list) ==
+ offsetof(struct vcpu_tdx, pi_wakeup_list));
+#endif
+
+static inline struct vcpu_pi *vcpu_to_pi(struct kvm_vcpu *vcpu)
+{
+ return (struct vcpu_pi *)vcpu;
+}
+
static inline struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu)
{
- return &(to_vmx(vcpu)->pi_desc);
+ return &vcpu_to_pi(vcpu)->pi_desc;
}
static int pi_try_set_control(struct pi_desc *pi_desc, u64 *pold, u64 new)
@@ -52,8 +73,8 @@ static int pi_try_set_control(struct pi_desc *pi_desc, u64 *pold, u64 new)
void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu)
{
- struct pi_desc *pi_desc = vcpu_to_pi_desc(vcpu);
- struct vcpu_vmx *vmx = to_vmx(vcpu);
+ struct vcpu_pi *vcpu_pi = vcpu_to_pi(vcpu);
+ struct pi_desc *pi_desc = &vcpu_pi->pi_desc;
struct pi_desc old, new;
unsigned long flags;
unsigned int dest;
@@ -90,7 +111,7 @@ void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu)
*/
if (pi_desc->nv == POSTED_INTR_WAKEUP_VECTOR) {
raw_spin_lock(&per_cpu(wakeup_vcpus_on_cpu_lock, vcpu->cpu));
- list_del(&vmx->pi_wakeup_list);
+ list_del(&vcpu_pi->pi_wakeup_list);
raw_spin_unlock(&per_cpu(wakeup_vcpus_on_cpu_lock, vcpu->cpu));
}
@@ -145,15 +166,15 @@ static bool vmx_can_use_vtd_pi(struct kvm *kvm)
*/
static void pi_enable_wakeup_handler(struct kvm_vcpu *vcpu)
{
- struct pi_desc *pi_desc = vcpu_to_pi_desc(vcpu);
- struct vcpu_vmx *vmx = to_vmx(vcpu);
+ struct vcpu_pi *vcpu_pi = vcpu_to_pi(vcpu);
+ struct pi_desc *pi_desc = &vcpu_pi->pi_desc;
struct pi_desc old, new;
unsigned long flags;
local_irq_save(flags);
raw_spin_lock(&per_cpu(wakeup_vcpus_on_cpu_lock, vcpu->cpu));
- list_add_tail(&vmx->pi_wakeup_list,
+ list_add_tail(&vcpu_pi->pi_wakeup_list,
&per_cpu(wakeup_vcpus_on_cpu, vcpu->cpu));
raw_spin_unlock(&per_cpu(wakeup_vcpus_on_cpu_lock, vcpu->cpu));
@@ -190,7 +211,8 @@ static bool vmx_needs_pi_wakeup(struct kvm_vcpu *vcpu)
* notification vector is switched to the one that calls
* back to the pi_wakeup_handler() function.
*/
- return vmx_can_use_ipiv(vcpu) || vmx_can_use_vtd_pi(vcpu->kvm);
+ return (vmx_can_use_ipiv(vcpu) && !is_td_vcpu(vcpu)) ||
+ vmx_can_use_vtd_pi(vcpu->kvm);
}
void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu)
@@ -200,7 +222,8 @@ void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu)
if (!vmx_needs_pi_wakeup(vcpu))
return;
- if (kvm_vcpu_is_blocking(vcpu) && !vmx_interrupt_blocked(vcpu))
+ if (kvm_vcpu_is_blocking(vcpu) &&
+ (is_td_vcpu(vcpu) || !vmx_interrupt_blocked(vcpu)))
pi_enable_wakeup_handler(vcpu);
/*
diff --git a/arch/x86/kvm/vmx/posted_intr.h b/arch/x86/kvm/vmx/posted_intr.h
index 26992076552e..2fe8222308b2 100644
--- a/arch/x86/kvm/vmx/posted_intr.h
+++ b/arch/x86/kvm/vmx/posted_intr.h
@@ -94,6 +94,17 @@ static inline bool pi_test_sn(struct pi_desc *pi_desc)
(unsigned long *)&pi_desc->control);
}
+struct vcpu_pi {
+ struct kvm_vcpu vcpu;
+
+ /* Posted interrupt descriptor */
+ struct pi_desc pi_desc;
+
+ /* Used if this vCPU is waiting for PI notification wakeup. */
+ struct list_head pi_wakeup_list;
+ /* Until here common layout betwwn vcpu_vmx and vcpu_tdx. */
+};
+
void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu);
void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu);
void pi_wakeup_handler(void);
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index f0e84f8773e9..ab5af39dd7b3 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -515,6 +515,7 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
fpstate_set_confidential(&vcpu->arch.guest_fpu);
vcpu->arch.apic->guest_apic_protected = true;
+ INIT_LIST_HEAD(&tdx->pi_wakeup_list);
vcpu->arch.efer = EFER_SCE | EFER_LME | EFER_LMA | EFER_NX;
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 1595c124899d..cee7b4bc0d0a 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -4,6 +4,7 @@
#ifdef CONFIG_INTEL_TDX_HOST
+#include "posted_intr.h"
#include "pmu_intel.h"
#include "tdx_ops.h"
@@ -59,6 +60,13 @@ union tdx_exit_reason {
struct vcpu_tdx {
struct kvm_vcpu vcpu;
+ /* Posted interrupt descriptor */
+ struct pi_desc pi_desc;
+
+ /* Used if this vCPU is waiting for PI notification wakeup. */
+ struct list_head pi_wakeup_list;
+ /* Until here same layout to struct vcpu_pi. */
+
unsigned long tdvpr_pa;
unsigned long *tdvpx_pa;
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 8a21988e091a..3e72cab788a6 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -245,6 +245,14 @@ struct nested_vmx {
struct vcpu_vmx {
struct kvm_vcpu vcpu;
+
+ /* Posted interrupt descriptor */
+ struct pi_desc pi_desc;
+
+ /* Used if this vCPU is waiting for PI notification wakeup. */
+ struct list_head pi_wakeup_list;
+ /* Until here same layout to struct vcpu_pi. */
+
u8 fail;
u8 x2apic_msr_bitmap_mode;
@@ -314,12 +322,6 @@ struct vcpu_vmx {
union vmx_exit_reason exit_reason;
- /* Posted interrupt descriptor */
- struct pi_desc pi_desc;
-
- /* Used if this vCPU is waiting for PI notification wakeup. */
- struct list_head pi_wakeup_list;
-
/* Support for a guest hypervisor (nested VMX) */
struct nested_vmx nested;
--
2.25.1
From: Sean Christopherson <[email protected]>
By necessity, TDX will use a different register ABI for hypercalls.
Break out the core functionality so that it may be reused for TDX.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 4 +++
arch/x86/kvm/x86.c | 54 ++++++++++++++++++++-------------
2 files changed, 37 insertions(+), 21 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 23dfb9b89980..50e3666ec6f6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2102,6 +2102,10 @@ static inline void kvm_clear_apicv_inhibit(struct kvm *kvm,
kvm_set_or_clear_apicv_inhibit(kvm, reason, false);
}
+unsigned long __kvm_emulate_hypercall(struct kvm_vcpu *vcpu, unsigned long nr,
+ unsigned long a0, unsigned long a1,
+ unsigned long a2, unsigned long a3,
+ int op_64_bit);
int kvm_emulate_hypercall(struct kvm_vcpu *vcpu);
int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 84e4b00cc21a..6f8eee8c0f2b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9767,26 +9767,15 @@ static int complete_hypercall_exit(struct kvm_vcpu *vcpu)
return kvm_skip_emulated_instruction(vcpu);
}
-int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
+unsigned long __kvm_emulate_hypercall(struct kvm_vcpu *vcpu, unsigned long nr,
+ unsigned long a0, unsigned long a1,
+ unsigned long a2, unsigned long a3,
+ int op_64_bit)
{
- unsigned long nr, a0, a1, a2, a3, ret;
- int op_64_bit;
-
- if (kvm_xen_hypercall_enabled(vcpu->kvm))
- return kvm_xen_hypercall(vcpu);
-
- if (kvm_hv_hypercall_enabled(vcpu))
- return kvm_hv_hypercall(vcpu);
-
- nr = kvm_rax_read(vcpu);
- a0 = kvm_rbx_read(vcpu);
- a1 = kvm_rcx_read(vcpu);
- a2 = kvm_rdx_read(vcpu);
- a3 = kvm_rsi_read(vcpu);
+ unsigned long ret;
trace_kvm_hypercall(nr, a0, a1, a2, a3);
- op_64_bit = is_64_bit_hypercall(vcpu);
if (!op_64_bit) {
nr &= 0xFFFFFFFF;
a0 &= 0xFFFFFFFF;
@@ -9795,11 +9784,6 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
a3 &= 0xFFFFFFFF;
}
- if (static_call(kvm_x86_get_cpl)(vcpu) != 0) {
- ret = -KVM_EPERM;
- goto out;
- }
-
ret = -KVM_ENOSYS;
switch (nr) {
@@ -9858,6 +9842,34 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
ret = -KVM_ENOSYS;
break;
}
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__kvm_emulate_hypercall);
+
+int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
+{
+ unsigned long nr, a0, a1, a2, a3, ret;
+ int op_64_bit;
+
+ if (kvm_xen_hypercall_enabled(vcpu->kvm))
+ return kvm_xen_hypercall(vcpu);
+
+ if (kvm_hv_hypercall_enabled(vcpu))
+ return kvm_hv_hypercall(vcpu);
+
+ nr = kvm_rax_read(vcpu);
+ a0 = kvm_rbx_read(vcpu);
+ a1 = kvm_rcx_read(vcpu);
+ a2 = kvm_rdx_read(vcpu);
+ a3 = kvm_rsi_read(vcpu);
+ op_64_bit = is_64_bit_hypercall(vcpu);
+
+ if (static_call(kvm_x86_get_cpl)(vcpu) != 0) {
+ ret = -KVM_EPERM;
+ goto out;
+ }
+
+ ret = __kvm_emulate_hypercall(vcpu, nr, a0, a1, a2, a3, op_64_bit);
out:
if (!op_64_bit)
ret = (u32)ret;
--
2.25.1
From: Sean Christopherson <[email protected]>
If APIC state is protected, i.e. the vCPU is a TDX guest, assume a timer
IRQ was injected when deciding whether or not to busy wait in the "timer
advanced" path. The "real" vIRR is not readable/writable, so trying to
query for a pending timer IRQ will return garbage.
Note, TDX can scour the PIR if it wants to be more precise and skip the
"wait" call entirely.
Signed-off-by: Sean Christopherson <[email protected]>
---
arch/x86/kvm/lapic.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index b2612a86789f..6b2e2d38a48b 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1734,8 +1734,17 @@ static void apic_update_lvtt(struct kvm_lapic *apic)
static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
- u32 reg = kvm_lapic_get_reg(apic, APIC_LVTT);
+ u32 reg;
+ /*
+ * Assume a timer IRQ was "injected" if the APIC is protected. KVM's
+ * copy of the vIRR is bogus, it's the responsibility of the caller to
+ * precisely check whether or not a timer IRQ is pending.
+ */
+ if (apic->guest_apic_protected)
+ return true;
+
+ reg = kvm_lapic_get_reg(apic, APIC_LVTT);
if (kvm_apic_hw_enabled(apic)) {
int vec = reg & APIC_VECTOR_MASK;
void *bitmap = apic->regs + APIC_ISR;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Implement TDG.VP.VMCALL<GetTdVmCallInfo> hypercall. If the input value is
zero, return success code and zero in output registers.
TDG.VP.VMCALL<GetTdVmCallInfo> hypercall is a subleaf of TDG.VP.VMCALL to
enumerate which TDG.VP.VMCALL sub leaves are supported. This hypercall is
for future enhancement of the Guest-Host-Communication Interface (GHCI)
specification. The GHCI version of 344426-001US defines it to require
input R12 to be zero and to return zero in output registers, R11, R12, R13,
and R14 so that guest TD enumerates no enhancement.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 853cfda99fed..10bbac208a9c 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1216,6 +1216,20 @@ static int tdx_emulate_wrmsr(struct kvm_vcpu *vcpu)
return 1;
}
+static int tdx_get_td_vm_call_info(struct kvm_vcpu *vcpu)
+{
+ if (tdvmcall_a0_read(vcpu))
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ else {
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ kvm_r11_write(vcpu, 0);
+ tdvmcall_a0_write(vcpu, 0);
+ tdvmcall_a1_write(vcpu, 0);
+ tdvmcall_a2_write(vcpu, 0);
+ }
+ return 1;
+}
+
static int tdx_map_gpa(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
@@ -1252,6 +1266,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
return tdx_emulate_rdmsr(vcpu);
case EXIT_REASON_MSR_WRITE:
return tdx_emulate_wrmsr(vcpu);
+ case TDG_VP_VMCALL_GET_TD_VM_CALL_INFO:
+ return tdx_get_td_vm_call_info(vcpu);
case TDG_VP_VMCALL_REPORT_FATAL_ERROR:
/*
* Exit to userspace device model for tear down.
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up handle_exit and handle_exit_irqoff methods and add a place holder
to handle VM exit. Add helper functions to get exit info, exit
qualification, etc.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/main.c | 37 +++++++++++++--
arch/x86/kvm/vmx/tdx.c | 97 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 10 ++++
3 files changed, 141 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index c3358cf1c8ef..caeddb212e50 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -240,6 +240,25 @@ static bool vt_protected_apic_has_interrupt(struct kvm_vcpu *vcpu)
return tdx_protected_apic_has_interrupt(vcpu);
}
+static int vt_handle_exit(struct kvm_vcpu *vcpu,
+ enum exit_fastpath_completion fastpath)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_handle_exit(vcpu, fastpath);
+
+ return vmx_handle_exit(vcpu, fastpath);
+}
+
+static void vt_handle_exit_irqoff(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_handle_exit_irqoff(vcpu);
+ return;
+ }
+
+ vmx_handle_exit_irqoff(vcpu);
+}
+
static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
struct pi_desc *pi = vcpu_to_pi_desc(vcpu);
@@ -446,6 +465,18 @@ static void vt_request_immediate_exit(struct kvm_vcpu *vcpu)
vmx_request_immediate_exit(vcpu);
}
+static void vt_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
+ u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_get_exit_info(vcpu, reason, info1, info2, intr_info,
+ error_code);
+ return;
+ }
+
+ vmx_get_exit_info(vcpu, reason, info1, info2, intr_info, error_code);
+}
+
static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
if (is_td_vcpu(vcpu))
@@ -542,7 +573,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vcpu_pre_run = vt_vcpu_pre_run,
.vcpu_run = vt_vcpu_run,
- .handle_exit = vmx_handle_exit,
+ .handle_exit = vt_handle_exit,
.skip_emulated_instruction = vmx_skip_emulated_instruction,
.update_emulated_instruction = vmx_update_emulated_instruction,
.set_interrupt_shadow = vt_set_interrupt_shadow,
@@ -577,7 +608,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.set_identity_map_addr = vmx_set_identity_map_addr,
.get_mt_mask = vt_get_mt_mask,
- .get_exit_info = vmx_get_exit_info,
+ .get_exit_info = vt_get_exit_info,
.vcpu_after_set_cpuid = vmx_vcpu_after_set_cpuid,
@@ -591,7 +622,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.load_mmu_pgd = vt_load_mmu_pgd,
.check_intercept = vmx_check_intercept,
- .handle_exit_irqoff = vmx_handle_exit_irqoff,
+ .handle_exit_irqoff = vt_handle_exit_irqoff,
.request_immediate_exit = vt_request_immediate_exit,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 44977fd3c0d1..478482dd331e 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -87,6 +87,26 @@ static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
}
+static __always_inline unsigned long tdexit_exit_qual(struct kvm_vcpu *vcpu)
+{
+ return kvm_rcx_read(vcpu);
+}
+
+static __always_inline unsigned long tdexit_ext_exit_qual(struct kvm_vcpu *vcpu)
+{
+ return kvm_rdx_read(vcpu);
+}
+
+static __always_inline unsigned long tdexit_gpa(struct kvm_vcpu *vcpu)
+{
+ return kvm_r8_read(vcpu);
+}
+
+static __always_inline unsigned long tdexit_intr_info(struct kvm_vcpu *vcpu)
+{
+ return kvm_r9_read(vcpu);
+}
+
static inline bool is_td_vcpu_created(struct vcpu_tdx *tdx)
{
return tdx->tdvpr_pa;
@@ -745,6 +765,25 @@ void tdx_inject_nmi(struct kvm_vcpu *vcpu)
td_management_write8(to_tdx(vcpu), TD_VCPU_PEND_NMI, 1);
}
+void tdx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ u16 exit_reason = tdx->exit_reason.basic;
+
+ if (exit_reason == EXIT_REASON_EXCEPTION_NMI)
+ vmx_handle_exception_nmi_irqoff(vcpu, tdexit_intr_info(vcpu));
+ else if (exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT)
+ vmx_handle_external_interrupt_irqoff(vcpu,
+ tdexit_intr_info(vcpu));
+}
+
+static int tdx_handle_triple_fault(struct kvm_vcpu *vcpu)
+{
+ vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN;
+ vcpu->mmio_needed = 0;
+ return 0;
+}
+
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
{
td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
@@ -1071,6 +1110,64 @@ void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
__vmx_deliver_posted_interrupt(vcpu, &tdx->pi_desc, vector);
}
+int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
+{
+ union tdx_exit_reason exit_reason = to_tdx(vcpu)->exit_reason;
+
+ /* See the comment of tdh_sept_seamcall(). */
+ if (unlikely(exit_reason.full == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT)))
+ return 1;
+
+ if (unlikely(exit_reason.full == TDX_SEAMCALL_UD)) {
+ kvm_spurious_fault();
+ /*
+ * In the case of reboot or kexec, loop with TDH.VP.ENTER and
+ * TDX_SEAMCALL_UD to avoid unnecessarily activity.
+ */
+ return 1;
+ }
+
+ if (unlikely(exit_reason.non_recoverable || exit_reason.error)) {
+ if (exit_reason.basic == EXIT_REASON_TRIPLE_FAULT)
+ return tdx_handle_triple_fault(vcpu);
+
+ kvm_pr_unimpl("TD exit 0x%llx, %d hkid 0x%x hkid pa 0x%llx\n",
+ exit_reason.full, exit_reason.basic,
+ to_kvm_tdx(vcpu->kvm)->hkid,
+ set_hkid_to_hpa(0, to_kvm_tdx(vcpu->kvm)->hkid));
+ goto unhandled_exit;
+ }
+
+ WARN_ON_ONCE(fastpath != EXIT_FASTPATH_NONE);
+
+ switch (exit_reason.basic) {
+ default:
+ break;
+ }
+
+unhandled_exit:
+ vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+ vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
+ vcpu->run->internal.ndata = 2;
+ vcpu->run->internal.data[0] = exit_reason.full;
+ vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu;
+ return 0;
+}
+
+void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
+ u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ *reason = tdx->exit_reason.full;
+
+ *info1 = tdexit_exit_qual(vcpu);
+ *info2 = tdexit_ext_exit_qual(vcpu);
+
+ *intr_info = tdexit_intr_info(vcpu);
+ *error_code = 0;
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index fbbbae685363..b6960631b71d 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -161,11 +161,16 @@ void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
void tdx_vcpu_put(struct kvm_vcpu *vcpu);
void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu);
+void tdx_handle_exit_irqoff(struct kvm_vcpu *vcpu);
+int tdx_handle_exit(struct kvm_vcpu *vcpu,
+ enum exit_fastpath_completion fastpath);
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
int trig_mode, int vector);
void tdx_inject_nmi(struct kvm_vcpu *vcpu);
+void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
+ u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -198,11 +203,16 @@ static inline void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_put(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) {}
static inline bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu) { return false; }
+static inline void tdx_handle_exit_irqoff(struct kvm_vcpu *vcpu) {}
+static inline int tdx_handle_exit(struct kvm_vcpu *vcpu,
+ enum exit_fastpath_completion fastpath) { return 0; }
static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
int trig_mode, int vector) {}
static inline void tdx_inject_nmi(struct kvm_vcpu *vcpu) {}
+static inline void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason, u64 *info1,
+ u64 *info2, u32 *intr_info, u32 *error_code) {}
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
2.25.1
From: Sean Christopherson <[email protected]>
TDX mostly handles NMI/exception exit mostly the same to VMX case. The
difference is how to retrieve exit qualification. To share the code with
TDX, move NMI/exception to a common header, common.h.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/common.h | 59 +++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 68 +++++----------------------------------
2 files changed, 67 insertions(+), 60 deletions(-)
diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
index 39ddead9d2bd..0dcf31e064d0 100644
--- a/arch/x86/kvm/vmx/common.h
+++ b/arch/x86/kvm/vmx/common.h
@@ -4,8 +4,67 @@
#include <linux/kvm_host.h>
+#include <asm/traps.h>
+
#include "posted_intr.h"
#include "mmu.h"
+#include "vmcs.h"
+#include "x86.h"
+
+extern unsigned long vmx_host_idt_base;
+void vmx_do_interrupt_irqoff(unsigned long entry);
+void vmx_do_nmi_irqoff(void);
+
+static inline void vmx_handle_nm_fault_irqoff(struct kvm_vcpu *vcpu)
+{
+ /*
+ * Save xfd_err to guest_fpu before interrupt is enabled, so the
+ * MSR value is not clobbered by the host activity before the guest
+ * has chance to consume it.
+ *
+ * Do not blindly read xfd_err here, since this exception might
+ * be caused by L1 interception on a platform which doesn't
+ * support xfd at all.
+ *
+ * Do it conditionally upon guest_fpu::xfd. xfd_err matters
+ * only when xfd contains a non-zero value.
+ *
+ * Queuing exception is done in vmx_handle_exit. See comment there.
+ */
+ if (vcpu->arch.guest_fpu.fpstate->xfd)
+ rdmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
+}
+
+static inline void vmx_handle_exception_irqoff(struct kvm_vcpu *vcpu,
+ u32 intr_info)
+{
+ /* if exit due to PF check for async PF */
+ if (is_page_fault(intr_info))
+ vcpu->arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
+ /* if exit due to NM, handle before interrupts are enabled */
+ else if (is_nm_fault(intr_info))
+ vmx_handle_nm_fault_irqoff(vcpu);
+ /* Handle machine checks before interrupts are enabled */
+ else if (is_machine_check(intr_info))
+ kvm_machine_check();
+}
+
+static inline void vmx_handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu,
+ u32 intr_info)
+{
+ unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK;
+ gate_desc *desc = (gate_desc *)vmx_host_idt_base + vector;
+
+ if (KVM_BUG(!is_external_intr(intr_info), vcpu->kvm,
+ "unexpected VM-Exit interrupt info: 0x%x", intr_info))
+ return;
+
+ kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ);
+ vmx_do_interrupt_irqoff(gate_offset(desc));
+ kvm_after_interrupt(vcpu);
+
+ vcpu->arch.at_instruction_boundary = true;
+}
u8 __vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio, bool check_cr0_cd);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index bbf286a5c338..0c973e9f4a70 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -526,7 +526,7 @@ static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx)
vmx->segment_cache.bitmask = 0;
}
-static unsigned long host_idt_base;
+unsigned long vmx_host_idt_base;
#if IS_ENABLED(CONFIG_HYPERV)
static bool __read_mostly enlightened_vmcs = true;
@@ -4265,7 +4265,7 @@ void vmx_set_constant_host_state(struct vcpu_vmx *vmx)
vmcs_write16(HOST_SS_SELECTOR, __KERNEL_DS); /* 22.2.4 */
vmcs_write16(HOST_TR_SELECTOR, GDT_ENTRY_TSS*8); /* 22.2.4 */
- vmcs_writel(HOST_IDTR_BASE, host_idt_base); /* 22.2.4 */
+ vmcs_writel(HOST_IDTR_BASE, vmx_host_idt_base); /* 22.2.4 */
vmcs_writel(HOST_RIP, (unsigned long)vmx_vmexit); /* 22.2.5 */
@@ -5162,7 +5162,7 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
intr_info = vmx_get_intr_info(vcpu);
/*
- * Machine checks are handled by handle_exception_irqoff(), or by
+ * Machine checks are handled by vmx_handle_exception_irqoff(), or by
* vmx_vcpu_run() if a #MC occurs on VM-Entry. NMIs are handled by
* vmx_vcpu_enter_exit().
*/
@@ -5170,7 +5170,7 @@ static int handle_exception_nmi(struct kvm_vcpu *vcpu)
return 1;
/*
- * Queue the exception here instead of in handle_nm_fault_irqoff().
+ * Queue the exception here instead of in vmx_handle_nm_fault_irqoff().
* This ensures the nested_vmx check is not skipped so vmexit can
* be reflected to L1 (when it intercepts #NM) before reaching this
* point.
@@ -6845,59 +6845,6 @@ void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
vmcs_write64(EOI_EXIT_BITMAP3, eoi_exit_bitmap[3]);
}
-void vmx_do_interrupt_irqoff(unsigned long entry);
-void vmx_do_nmi_irqoff(void);
-
-static void handle_nm_fault_irqoff(struct kvm_vcpu *vcpu)
-{
- /*
- * Save xfd_err to guest_fpu before interrupt is enabled, so the
- * MSR value is not clobbered by the host activity before the guest
- * has chance to consume it.
- *
- * Do not blindly read xfd_err here, since this exception might
- * be caused by L1 interception on a platform which doesn't
- * support xfd at all.
- *
- * Do it conditionally upon guest_fpu::xfd. xfd_err matters
- * only when xfd contains a non-zero value.
- *
- * Queuing exception is done in vmx_handle_exit. See comment there.
- */
- if (vcpu->arch.guest_fpu.fpstate->xfd)
- rdmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
-}
-
-static void handle_exception_irqoff(struct kvm_vcpu *vcpu, u32 intr_info)
-{
- /* if exit due to PF check for async PF */
- if (is_page_fault(intr_info))
- vcpu->arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
- /* if exit due to NM, handle before interrupts are enabled */
- else if (is_nm_fault(intr_info))
- handle_nm_fault_irqoff(vcpu);
- /* Handle machine checks before interrupts are enabled */
- else if (is_machine_check(intr_info))
- kvm_machine_check();
-}
-
-static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu,
- u32 intr_info)
-{
- unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK;
- gate_desc *desc = (gate_desc *)host_idt_base + vector;
-
- if (KVM_BUG(!is_external_intr(intr_info), vcpu->kvm,
- "unexpected VM-Exit interrupt info: 0x%x", intr_info))
- return;
-
- kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ);
- vmx_do_interrupt_irqoff(gate_offset(desc));
- kvm_after_interrupt(vcpu);
-
- vcpu->arch.at_instruction_boundary = true;
-}
-
void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -6906,9 +6853,10 @@ void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
return;
if (vmx->exit_reason.basic == EXIT_REASON_EXTERNAL_INTERRUPT)
- handle_external_interrupt_irqoff(vcpu, vmx_get_intr_info(vcpu));
+ vmx_handle_external_interrupt_irqoff(vcpu,
+ vmx_get_intr_info(vcpu));
else if (vmx->exit_reason.basic == EXIT_REASON_EXCEPTION_NMI)
- handle_exception_irqoff(vcpu, vmx_get_intr_info(vcpu));
+ vmx_handle_exception_irqoff(vcpu, vmx_get_intr_info(vcpu));
}
/*
@@ -8202,7 +8150,7 @@ __init int vmx_hardware_setup(void)
int r;
store_idt(&dt);
- host_idt_base = dt.address;
+ vmx_host_idt_base = dt.address;
vmx_setup_user_return_msrs();
--
2.25.1
From: Sean Christopherson <[email protected]>
Add flag and hook to KVM's local APIC management to support determining
whether or not a TDX guest as a pending IRQ. For TDX vCPUs, the virtual
APIC page is owned by the TDX module and cannot be accessed by KVM. As a
result, registers that are virtualized by the CPU, e.g. PPR, cannot be
read or written by KVM. To deliver interrupts for TDX guests, KVM must
send an IRQ to the CPU on the posted interrupt notification vector. And
to determine if TDX vCPU has a pending interrupt, KVM must check if there
is an outstanding notification.
Return "no interrupt" in kvm_apic_has_interrupt() if the guest APIC is
protected to short-circuit the various other flows that try to pull an
IRQ out of the vAPIC, the only valid operation is querying _if_ an IRQ is
pending, KVM can't do anything based on _which_ IRQ is pending.
Intentionally omit sanity checks from other flows, e.g. PPR update, so as
not to degrade non-TDX guests with unnecessary checks. A well-behaved KVM
and userspace will never reach those flows for TDX guests, but reaching
them is not fatal if something does go awry.
Note, this doesn't handle interrupts that have been delivered to the vCPU
but not yet recognized by the core, i.e. interrupts that are sitting in
vmcs.GUEST_INTR_STATUS. Querying that state requires a SEAMCALL and will
be supported in a future patch.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/irq.c | 3 +++
arch/x86/kvm/lapic.c | 3 +++
arch/x86/kvm/lapic.h | 2 ++
arch/x86/kvm/vmx/main.c | 10 ++++++++++
arch/x86/kvm/vmx/tdx.c | 6 ++++++
arch/x86/kvm/vmx/x86_ops.h | 2 ++
8 files changed, 28 insertions(+)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 2681300ce142..e1242c4b248f 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -118,6 +118,7 @@ KVM_X86_OP_OPTIONAL(pi_update_irte)
KVM_X86_OP_OPTIONAL(pi_start_assignment)
KVM_X86_OP_OPTIONAL(apicv_post_state_restore)
KVM_X86_OP_OPTIONAL_RET0(dy_apicv_has_pending_interrupt)
+KVM_X86_OP_OPTIONAL(protected_apic_has_interrupt)
KVM_X86_OP_OPTIONAL(set_hv_timer)
KVM_X86_OP_OPTIONAL(cancel_hv_timer)
KVM_X86_OP(setup_mce)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 3e00fd1eb136..23dfb9b89980 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1766,6 +1766,7 @@ struct kvm_x86_ops {
void (*pi_start_assignment)(struct kvm *kvm);
void (*apicv_post_state_restore)(struct kvm_vcpu *vcpu);
bool (*dy_apicv_has_pending_interrupt)(struct kvm_vcpu *vcpu);
+ bool (*protected_apic_has_interrupt)(struct kvm_vcpu *vcpu);
int (*set_hv_timer)(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
bool *expired);
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index b2c397dd2bc6..fd6af5530c32 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -100,6 +100,9 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
if (kvm_cpu_has_extint(v))
return 1;
+ if (lapic_in_kernel(v) && v->arch.apic->guest_apic_protected)
+ return static_call(kvm_x86_protected_apic_has_interrupt)(v);
+
return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
}
EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index e542cf285b51..b2612a86789f 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2814,6 +2814,9 @@ int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
if (!kvm_apic_present(vcpu))
return -1;
+ if (apic->guest_apic_protected)
+ return -1;
+
__apic_update_ppr(apic, &ppr);
return apic_has_interrupt_for_ppr(apic, ppr);
}
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 0a0ea4b5dd8c..749b7b629c47 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -66,6 +66,8 @@ struct kvm_lapic {
bool sw_enabled;
bool irr_pending;
bool lvt0_in_nmi_mode;
+ /* Select registers in the vAPIC cannot be read/written. */
+ bool guest_apic_protected;
/* Number of bits set in ISR. */
s16 isr_count;
/* The highest vector set in ISR; if -1 - invalid, must scan ISR. */
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 5d7164557c6c..75d74aa79446 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -95,6 +95,8 @@ static __init int vt_hardware_setup(void)
if (enable_tdx)
vt_x86_ops.tlb_remote_flush = vt_tlb_remote_flush;
+ else
+ vt_x86_ops.protected_apic_has_interrupt = NULL;
return 0;
}
@@ -231,6 +233,13 @@ static void vt_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
vmx_vcpu_load(vcpu, cpu);
}
+static bool vt_protected_apic_has_interrupt(struct kvm_vcpu *vcpu)
+{
+ KVM_BUG_ON(!is_td_vcpu(vcpu), vcpu->kvm);
+
+ return tdx_protected_apic_has_interrupt(vcpu);
+}
+
static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu)) {
@@ -423,6 +432,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.sync_pir_to_irr = vmx_sync_pir_to_irr,
.deliver_interrupt = vmx_deliver_interrupt,
.dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,
+ .protected_apic_has_interrupt = vt_protected_apic_has_interrupt,
.set_tss_addr = vmx_set_tss_addr,
.set_identity_map_addr = vmx_set_identity_map_addr,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index e354fd08cbaf..f0e84f8773e9 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -514,6 +514,7 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
return -EINVAL;
fpstate_set_confidential(&vcpu->arch.guest_fpu);
+ vcpu->arch.apic->guest_apic_protected = true;
vcpu->arch.efer = EFER_SCE | EFER_LME | EFER_LMA | EFER_NX;
@@ -552,6 +553,11 @@ void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
local_irq_enable();
}
+bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu)
+{
+ return pi_has_pending_interrupt(vcpu);
+}
+
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
{
struct vcpu_tdx *tdx = to_tdx(vcpu);
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 2dace209e7d3..4c788f34b777 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -161,6 +161,7 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu);
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
void tdx_vcpu_put(struct kvm_vcpu *vcpu);
void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
+bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu);
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -193,6 +194,7 @@ static inline fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) { return EXIT_FASTP
static inline void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_put(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) {}
+static inline bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu) { return false; }
static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
2.25.1
From: Yao Yuan <[email protected]>
TDX module passes control back to VMM if it failed to vmentry for a TD, use
same exit reason to notify user space, align with VMX.
If VMM corrupted TD VMCS, machine check during entry can happens. vm exit
reason will be EXIT_REASON_MCE_DURING_VMENTRY. If VMM corrupted TD VMCS
with debug TD by TDH.VP.WR, the exit reason would be
EXIT_REASON_INVALID_STATE or EXIT_REASON_MSR_LOAD_FAIL.
Signed-off-by: Yao Yuan <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 478482dd331e..7e0fc3d5f513 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1138,6 +1138,28 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
goto unhandled_exit;
}
+ /*
+ * When TDX module saw VMEXIT_REASON_FAILED_VMENTER_MC etc, TDH.VP.ENTER
+ * returns with TDX_SUCCESS | exit_reason with failed_vmentry = 1.
+ * Because TDX module maintains TD VMCS correctness, usually vmentry
+ * failure shouldn't happen. In some corner cases it can happen. For
+ * example
+ * - machine check during entry: EXIT_REASON_MCE_DURING_VMENTRY
+ * - TDH.VP.WR with debug TD. VMM can corrupt TD VMCS
+ * - EXIT_REASON_INVALID_STATE
+ * - EXIT_REASON_MSR_LOAD_FAIL
+ */
+ if (unlikely(exit_reason.failed_vmentry)) {
+ pr_err("TDExit: exit_reason 0x%016llx qualification=%016lx ext_qualification=%016lx\n",
+ exit_reason.full, tdexit_exit_qual(vcpu), tdexit_ext_exit_qual(vcpu));
+ vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ vcpu->run->fail_entry.hardware_entry_failure_reason
+ = exit_reason.full;
+ vcpu->run->fail_entry.cpu = vcpu->arch.last_vmentry_cpu;
+
+ return 0;
+ }
+
WARN_ON_ONCE(fastpath != EXIT_FASTPATH_NONE);
switch (exit_reason.basic) {
--
2.25.1
From: Isaku Yamahata <[email protected]>
The TDX module specification defines TDG.VP.VMCALL API (TDVMCALL for short)
for the guest TD to call hypercall to VMM. When the guest TD issues
TDG.VP.VMCALL, the guest TD exits to VMM with a new exit reason of
TDVMCALL. The arguments from the guest TD and returned values from the VMM
are passed in the guest registers. The guest RCX registers indicates which
registers are used. Define helper functions to access those registers as
ABI.
Define the TDVMCALL exit reason, which is carved out from the VMX exit
reason namespace as the TDVMCALL exit from TDX guest to TDX-SEAM is really
just a VM-Exit. Add a place holder to handle TDVMCALL exit.
Co-developed-by: Xiaoyao Li <[email protected]>
Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/uapi/asm/vmx.h | 4 ++-
arch/x86/kvm/vmx/tdx.c | 56 ++++++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 13 ++++++++
3 files changed, 71 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h
index b3a30ef3efdd..f0f4a4cf84a7 100644
--- a/arch/x86/include/uapi/asm/vmx.h
+++ b/arch/x86/include/uapi/asm/vmx.h
@@ -93,6 +93,7 @@
#define EXIT_REASON_TPAUSE 68
#define EXIT_REASON_BUS_LOCK 74
#define EXIT_REASON_NOTIFY 75
+#define EXIT_REASON_TDCALL 77
#define VMX_EXIT_REASONS \
{ EXIT_REASON_EXCEPTION_NMI, "EXCEPTION_NMI" }, \
@@ -156,7 +157,8 @@
{ EXIT_REASON_UMWAIT, "UMWAIT" }, \
{ EXIT_REASON_TPAUSE, "TPAUSE" }, \
{ EXIT_REASON_BUS_LOCK, "BUS_LOCK" }, \
- { EXIT_REASON_NOTIFY, "NOTIFY" }
+ { EXIT_REASON_NOTIFY, "NOTIFY" }, \
+ { EXIT_REASON_TDCALL, "TDCALL" }
#define VMX_EXIT_REASON_FLAGS \
{ VMX_EXIT_REASONS_FAILED_VMENTRY, "FAILED_VMENTRY" }
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index f7840232be85..b3cac901a32f 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -107,6 +107,41 @@ static __always_inline unsigned long tdexit_intr_info(struct kvm_vcpu *vcpu)
return kvm_r9_read(vcpu);
}
+#define BUILD_TDVMCALL_ACCESSORS(param, gpr) \
+static __always_inline \
+unsigned long tdvmcall_##param##_read(struct kvm_vcpu *vcpu) \
+{ \
+ return kvm_##gpr##_read(vcpu); \
+} \
+static __always_inline void tdvmcall_##param##_write(struct kvm_vcpu *vcpu, \
+ unsigned long val) \
+{ \
+ kvm_##gpr##_write(vcpu, val); \
+}
+BUILD_TDVMCALL_ACCESSORS(a0, r12);
+BUILD_TDVMCALL_ACCESSORS(a1, r13);
+BUILD_TDVMCALL_ACCESSORS(a2, r14);
+BUILD_TDVMCALL_ACCESSORS(a3, r15);
+
+static __always_inline unsigned long tdvmcall_exit_type(struct kvm_vcpu *vcpu)
+{
+ return kvm_r10_read(vcpu);
+}
+static __always_inline unsigned long tdvmcall_leaf(struct kvm_vcpu *vcpu)
+{
+ return kvm_r11_read(vcpu);
+}
+static __always_inline void tdvmcall_set_return_code(struct kvm_vcpu *vcpu,
+ long val)
+{
+ kvm_r10_write(vcpu, val);
+}
+static __always_inline void tdvmcall_set_return_val(struct kvm_vcpu *vcpu,
+ unsigned long val)
+{
+ kvm_r11_write(vcpu, val);
+}
+
static inline bool is_td_vcpu_created(struct vcpu_tdx *tdx)
{
return tdx->tdvpr_pa;
@@ -724,7 +759,8 @@ static noinstr void tdx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
struct vcpu_tdx *tdx)
{
guest_enter_irqoff();
- tdx->exit_reason.full = __tdx_vcpu_run(tdx->tdvpr_pa, vcpu->arch.regs, 0);
+ tdx->exit_reason.full = __tdx_vcpu_run(tdx->tdvpr_pa, vcpu->arch.regs,
+ tdx->tdvmcall.regs_mask);
guest_exit_irqoff();
}
@@ -757,6 +793,11 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
tdx_complete_interrupts(vcpu);
+ if (tdx->exit_reason.basic == EXIT_REASON_TDCALL)
+ tdx->tdvmcall.rcx = vcpu->arch.regs[VCPU_REGS_RCX];
+ else
+ tdx->tdvmcall.rcx = 0;
+
return EXIT_FASTPATH_NONE;
}
@@ -803,6 +844,17 @@ static int tdx_handle_triple_fault(struct kvm_vcpu *vcpu)
return 0;
}
+static int handle_tdvmcall(struct kvm_vcpu *vcpu)
+{
+ switch (tdvmcall_leaf(vcpu)) {
+ default:
+ break;
+ }
+
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+}
+
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
{
td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
@@ -1228,6 +1280,8 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
return tdx_handle_exception(vcpu);
case EXIT_REASON_EXTERNAL_INTERRUPT:
return tdx_handle_external_interrupt(vcpu);
+ case EXIT_REASON_TDCALL:
+ return handle_tdvmcall(vcpu);
case EXIT_REASON_EPT_VIOLATION:
return tdx_handle_ept_violation(vcpu);
case EXIT_REASON_EPT_MISCONFIG:
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index cee7b4bc0d0a..fa44a1a9295f 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -72,6 +72,19 @@ struct vcpu_tdx {
struct list_head cpu_list;
+ union {
+ struct {
+ union {
+ struct {
+ u16 gpr_mask;
+ u16 xmm_mask;
+ };
+ u32 regs_mask;
+ };
+ u32 reserved;
+ };
+ u64 rcx;
+ } tdvmcall;
union tdx_exit_reason exit_reason;
bool initialized;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because TDX protects TDX guest state from VMM, instructions in guest memory
cannot be emulated. Implement methods to ignore guest instruction
emulator.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 07dfbf9a8b23..59fa63146c8d 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -332,6 +332,30 @@ static void vt_enable_smi_window(struct kvm_vcpu *vcpu)
}
#endif
+static bool vt_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
+ void *insn, int insn_len)
+{
+ if (is_td_vcpu(vcpu))
+ return false;
+
+ return vmx_can_emulate_instruction(vcpu, emul_type, insn, insn_len);
+}
+
+static int vt_check_intercept(struct kvm_vcpu *vcpu,
+ struct x86_instruction_info *info,
+ enum x86_intercept_stage stage,
+ struct x86_exception *exception)
+{
+ /*
+ * This call back is triggered by the x86 instruction emulator. TDX
+ * doesn't allow guest memory inspection.
+ */
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return X86EMUL_UNHANDLEABLE;
+
+ return vmx_check_intercept(vcpu, info, stage, exception);
+}
+
static bool vt_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu))
@@ -940,7 +964,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.load_mmu_pgd = vt_load_mmu_pgd,
- .check_intercept = vmx_check_intercept,
+ .check_intercept = vt_check_intercept,
.handle_exit_irqoff = vt_handle_exit_irqoff,
.request_immediate_exit = vt_request_immediate_exit,
@@ -969,7 +993,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.enable_smi_window = vt_enable_smi_window,
#endif
- .can_emulate_instruction = vmx_can_emulate_instruction,
+ .can_emulate_instruction = vt_can_emulate_instruction,
.apic_init_signal_blocked = vt_apic_init_signal_blocked,
.migrate_timers = vmx_migrate_timers,
--
2.25.1
From: Sean Christopherson <[email protected]>
Export kvm_io_bus_read and kvm_mmio tracepoint and wire up TDX PV MMIO
hypercall to the KVM backend functions.
kvm_io_bus_read/write() searches KVM device emulated in kernel of the given
MMIO address and emulates the MMIO. As TDX PV MMIO also needs it, export
kvm_io_bus_read(). kvm_io_bus_write() is already exported. TDX PV MMIO
emulates some of MMIO itself. To add trace point consistently with x86
kvm, export kvm_mmio tracepoint.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 114 +++++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/x86.c | 1 +
virt/kvm/kvm_main.c | 2 +
3 files changed, 117 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 12cc670eddf7..5f873fef9cb5 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1069,6 +1069,118 @@ static int tdx_emulate_io(struct kvm_vcpu *vcpu)
return ret;
}
+static int tdx_complete_mmio(struct kvm_vcpu *vcpu)
+{
+ unsigned long val = 0;
+ gpa_t gpa;
+ int size;
+
+ KVM_BUG_ON(vcpu->mmio_needed != 1, vcpu->kvm);
+ vcpu->mmio_needed = 0;
+
+ if (!vcpu->mmio_is_write) {
+ gpa = vcpu->mmio_fragments[0].gpa;
+ size = vcpu->mmio_fragments[0].len;
+
+ memcpy(&val, vcpu->run->mmio.data, size);
+ tdvmcall_set_return_val(vcpu, val);
+ trace_kvm_mmio(KVM_TRACE_MMIO_READ, size, gpa, &val);
+ }
+ return 1;
+}
+
+static inline int tdx_mmio_write(struct kvm_vcpu *vcpu, gpa_t gpa, int size,
+ unsigned long val)
+{
+ if (kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, gpa, size, &val) &&
+ kvm_io_bus_write(vcpu, KVM_MMIO_BUS, gpa, size, &val))
+ return -EOPNOTSUPP;
+
+ trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, size, gpa, &val);
+ return 0;
+}
+
+static inline int tdx_mmio_read(struct kvm_vcpu *vcpu, gpa_t gpa, int size)
+{
+ unsigned long val;
+
+ if (kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev, gpa, size, &val) &&
+ kvm_io_bus_read(vcpu, KVM_MMIO_BUS, gpa, size, &val))
+ return -EOPNOTSUPP;
+
+ tdvmcall_set_return_val(vcpu, val);
+ trace_kvm_mmio(KVM_TRACE_MMIO_READ, size, gpa, &val);
+ return 0;
+}
+
+static int tdx_emulate_mmio(struct kvm_vcpu *vcpu)
+{
+ struct kvm_memory_slot *slot;
+ int size, write, r;
+ unsigned long val;
+ gpa_t gpa;
+
+ KVM_BUG_ON(vcpu->mmio_needed, vcpu->kvm);
+
+ size = tdvmcall_a0_read(vcpu);
+ write = tdvmcall_a1_read(vcpu);
+ gpa = tdvmcall_a2_read(vcpu);
+ val = write ? tdvmcall_a3_read(vcpu) : 0;
+
+ if (size != 1 && size != 2 && size != 4 && size != 8)
+ goto error;
+ if (write != 0 && write != 1)
+ goto error;
+
+ /* Strip the shared bit, allow MMIO with and without it set. */
+ gpa = gpa & ~gfn_to_gpa(kvm_gfn_shared_mask(vcpu->kvm));
+
+ if (size > 8u || ((gpa + size - 1) ^ gpa) & PAGE_MASK)
+ goto error;
+
+ slot = kvm_vcpu_gfn_to_memslot(vcpu, gpa_to_gfn(gpa));
+ if (slot && !(slot->flags & KVM_MEMSLOT_INVALID))
+ goto error;
+
+ if (!kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, gpa, 0, NULL)) {
+ trace_kvm_fast_mmio(gpa);
+ return 1;
+ }
+
+ if (write)
+ r = tdx_mmio_write(vcpu, gpa, size, val);
+ else
+ r = tdx_mmio_read(vcpu, gpa, size);
+ if (!r) {
+ /* Kernel completed device emulation. */
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ return 1;
+ }
+
+ /* Request the device emulation to userspace device model. */
+ vcpu->mmio_needed = 1;
+ vcpu->mmio_is_write = write;
+ vcpu->arch.complete_userspace_io = tdx_complete_mmio;
+
+ vcpu->run->mmio.phys_addr = gpa;
+ vcpu->run->mmio.len = size;
+ vcpu->run->mmio.is_write = write;
+ vcpu->run->exit_reason = KVM_EXIT_MMIO;
+
+ if (write) {
+ memcpy(vcpu->run->mmio.data, &val, size);
+ } else {
+ vcpu->mmio_fragments[0].gpa = gpa;
+ vcpu->mmio_fragments[0].len = size;
+ trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, size, gpa, NULL);
+ }
+ return 0;
+
+error:
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -1081,6 +1193,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
return tdx_emulate_hlt(vcpu);
case EXIT_REASON_IO_INSTRUCTION:
return tdx_emulate_io(vcpu);
+ case EXIT_REASON_EPT_VIOLATION:
+ return tdx_emulate_mmio(vcpu);
default:
break;
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6f8eee8c0f2b..d18b6300b8d2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -13604,6 +13604,7 @@ bool kvm_arch_dirty_log_supported(struct kvm *kvm)
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_mmio);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e9f8225f3406..79e3c228bedf 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2683,6 +2683,7 @@ struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn
return NULL;
}
+EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot);
bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
{
@@ -5839,6 +5840,7 @@ int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
r = __kvm_io_bus_read(vcpu, bus, &range, val);
return r < 0 ? r : 0;
}
+EXPORT_SYMBOL_GPL(kvm_io_bus_read);
/* Caller must hold slots_lock. */
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
--
2.25.1
From: Isaku Yamahata <[email protected]>
The TDX Guest-Host communication interface (GHCI) specification defines
the ABI for the guest TD to issue hypercall. It reserves vendor specific
arguments for VMM specific use. Use it as KVM hypercall and handle it.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index b3cac901a32f..12af9a763ff4 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -844,8 +844,39 @@ static int tdx_handle_triple_fault(struct kvm_vcpu *vcpu)
return 0;
}
+static int tdx_emulate_vmcall(struct kvm_vcpu *vcpu)
+{
+ unsigned long nr, a0, a1, a2, a3, ret;
+
+ /*
+ * ABI for KVM tdvmcall argument:
+ * In Guest-Hypervisor Communication Interface(GHCI) specification,
+ * Non-zero leaf number (R10 != 0) is defined to indicate
+ * vendor-specific. KVM uses this for KVM hypercall. NOTE: KVM
+ * hypercall number starts from one. Zero isn't used for KVM hypercall
+ * number.
+ *
+ * R10: KVM hypercall number
+ * arguments: R11, R12, R13, R14.
+ */
+ nr = kvm_r10_read(vcpu);
+ a0 = kvm_r11_read(vcpu);
+ a1 = kvm_r12_read(vcpu);
+ a2 = kvm_r13_read(vcpu);
+ a3 = kvm_r14_read(vcpu);
+
+ ret = __kvm_emulate_hypercall(vcpu, nr, a0, a1, a2, a3, true);
+
+ tdvmcall_set_return_code(vcpu, ret);
+
+ return 1;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
+ if (tdvmcall_exit_type(vcpu))
+ return tdx_emulate_vmcall(vcpu);
+
switch (tdvmcall_leaf(vcpu)) {
default:
break;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Add a high level design document on TDX changes to TDP MMU.
Signed-off-by: Isaku Yamahata <[email protected]>
Co-developed-by: Bagas Sanjaya <[email protected]>
Signed-off-by: Bagas Sanjaya <[email protected]>
---
Documentation/virt/kvm/index.rst | 1 +
Documentation/virt/kvm/tdx-tdp-mmu.rst | 417 +++++++++++++++++++++++++
2 files changed, 418 insertions(+)
create mode 100644 Documentation/virt/kvm/tdx-tdp-mmu.rst
diff --git a/Documentation/virt/kvm/index.rst b/Documentation/virt/kvm/index.rst
index 41d1e59a65be..40ffc25f3cd1 100644
--- a/Documentation/virt/kvm/index.rst
+++ b/Documentation/virt/kvm/index.rst
@@ -21,4 +21,5 @@ KVM
review-checklist
intel-tdx
+ tdx-tdp-mmu
intel-tdx-layer-status.rst
diff --git a/Documentation/virt/kvm/tdx-tdp-mmu.rst b/Documentation/virt/kvm/tdx-tdp-mmu.rst
new file mode 100644
index 000000000000..2d91c94e6d8f
--- /dev/null
+++ b/Documentation/virt/kvm/tdx-tdp-mmu.rst
@@ -0,0 +1,417 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Design of TDP MMU for TDX support
+=================================
+This document describes a (high level) design for TDX support of KVM TDP MMU of
+x86 KVM.
+
+In this document, we use "TD" or "guest TD" to differentiate it from the current
+"VM" (Virtual Machine), which is supported by KVM today.
+
+
+Background of TDX
+=================
+TD private memory is designed to hold TD private content, encrypted by the CPU
+using the TD ephemeral key. An encryption engine holds a table of encryption
+keys, and an encryption key is selected for each memory transaction based on a
+Host Key Identifier (HKID). By design, the host VMM does not have access to the
+encryption keys.
+
+In the first generation of MKTME, HKID is "stolen" from the physical address by
+allocating a configurable number of bits from the top of the physical address.
+The HKID space is partitioned into shared HKIDs for legacy MKTME accesses and
+private HKIDs for SEAM-mode-only accesses. We use 0 for the shared HKID on the
+host so that MKTME can be opaque or bypassed on the host.
+
+During TDX non-root operation (i.e. guest TD), memory accesses can be qualified
+as either shared or private, based on the value of a new SHARED bit in the Guest
+Physical Address (GPA). The CPU translates shared GPAs using the usual VMX EPT
+(Extended Page Table) or "Shared EPT" (in this document), which resides in the
+host VMM memory. The Shared EPT is directly managed by the host VMM - the same
+as with the current VMX. Since guest TDs usually require I/O, and the data
+exchange needs to be done via shared memory, thus KVM needs to use the current
+EPT functionality even for TDs.
+
+The CPU translates private GPAs using a separate Secure EPT. The Secure EPT
+pages are encrypted and integrity-protected with the TD's ephemeral private key.
+Secure EPT can be managed _indirectly_ by the host VMM, using the TDX interface
+functions (SEAMCALLs), and thus conceptually Secure EPT is a subset of EPT
+because not all functionalities are available.
+
+Since the execution of such interface functions takes much longer time than
+accessing memory directly, in KVM we use the existing TDP code to mirror the
+Secure EPT for the TD. And we think there are at least two options today in
+terms of the timing for executing such SEAMCALLs:
+
+1. synchronous, i.e. while walking the TDP page tables, or
+2. post-walk, i.e. record what needs to be done to the real Secure EPT during
+ the walk, and execute SEAMCALLs later.
+
+The option 1 seems to be more intuitive and simpler, but the Secure EPT
+concurrency rules are different from the ones of the TDP or EPT. For example,
+MEM.SEPT.RD acquire shared access to the whole Secure EPT tree of the target
+
+Secure EPT(SEPT) operations
+---------------------------
+Secure EPT is an Extended Page Table for GPA-to-HPA translation of TD private
+HPA. A Secure EPT is designed to be encrypted with the TD's ephemeral private
+key. SEPT pages are allocated by the host VMM via Intel TDX functions, but their
+content is intended to be hidden and is not architectural.
+
+Unlike the conventional EPT, the CPU can't directly read/write its entry.
+Instead, TDX SEAMCALL API is used. Several SEAMCALLs correspond to operation on
+the EPT entry.
+
+* TDH.MEM.SEPT.ADD():
+
+ Add a secure EPT page from the secure EPT tree. This corresponds to updating
+ the non-leaf EPT entry with present bit set
+
+* TDH.MEM.SEPT.REMOVE():
+
+ Remove the secure page from the secure EPT tree. There is no corresponding
+ to the EPT operation.
+
+* TDH.MEM.SEPT.RD():
+
+ Read the secure EPT entry. This corresponds to reading the EPT entry as
+ memory. Please note that this is much slower than direct memory reading.
+
+* TDH.MEM.PAGE.ADD() and TDH.MEM.PAGE.AUG():
+
+ Add a private page to the secure EPT tree. This corresponds to updating the
+ leaf EPT entry with present bit set.
+
+* THD.MEM.PAGE.REMOVE():
+
+ Remove a private page from the secure EPT tree. There is no corresponding
+ to the EPT operation.
+
+* TDH.MEM.RANGE.BLOCK():
+
+ This (mostly) corresponds to clearing the present bit of the leaf EPT entry.
+ Note that the private page is still linked in the secure EPT. To remove it
+ from the secure EPT, TDH.MEM.SEPT.REMOVE() and TDH.MEM.PAGE.REMOVE() needs to
+ be called.
+
+* TDH.MEM.TRACK():
+
+ Increment the TLB epoch counter. This (mostly) corresponds to EPT TLB flush.
+ Note that the private page is still linked in the secure EPT. To remove it
+ from the secure EPT, tdh_mem_page_remove() needs to be called.
+
+
+Adding private page
+-------------------
+The procedure of populating the private page looks as follows.
+
+1. TDH.MEM.SEPT.ADD(512G level)
+2. TDH.MEM.SEPT.ADD(1G level)
+3. TDH.MEM.SEPT.ADD(2M level)
+4. TDH.MEM.PAGE.AUG(4K level)
+
+Those operations correspond to updating the EPT entries.
+
+Dropping private page and TLB shootdown
+---------------------------------------
+The procedure of dropping the private page looks as follows.
+
+1. TDH.MEM.RANGE.BLOCK(4K level)
+
+ This mostly corresponds to clear the present bit in the EPT entry. This
+ prevents (or blocks) TLB entry from creating in the future. Note that the
+ private page is still linked in the secure EPT tree and the existing cache
+ entry in the TLB isn't flushed.
+
+2. TDH.MEM.TRACK(range) and TLB shootdown
+
+ This mostly corresponds to the EPT TLB shootdown. Because all vcpus share
+ the same Secure EPT, all vcpus need to flush TLB.
+
+ * TDH.MEM.TRACK(range) by one vcpu. It increments the global internal TLB
+ epoch counter.
+
+ * send IPI to remote vcpus
+ * Other vcpu exits to VMM from guest TD and then re-enter. TDH.VP.ENTER().
+ * TDH.VP.ENTER() checks the TLB epoch counter and If its TLB is old, flush
+ TLB.
+
+ Note that only single vcpu issues tdh_mem_track().
+
+ Note that the private page is still linked in the secure EPT tree, unlike the
+ conventional EPT.
+
+3. TDH.MEM.PAGE.PROMOTE, TDH.MEM.PAGEDEMOTE(), TDH.MEM.PAGE.RELOCATE(), or
+ TDH.MEM.PAGE.REMOVE()
+
+ There is no corresponding operation to the conventional EPT.
+
+ * When changing page size (e.g. 4K <-> 2M) TDH.MEM.PAGE.PROMOTE() or
+ TDH.MEM.PAGE.DEMOTE() is used. During those operation, the guest page is
+ kept referenced in the Secure EPT.
+
+ * When migrating page, TDH.MEM.PAGE.RELOCATE(). This requires both source
+ page and destination page.
+ * when destroying TD, TDH.MEM.PAGE.REMOVE() removes the private page from the
+ secure EPT tree. In this case TLB shootdown is not needed because vcpus
+ don't run any more.
+
+The basic idea for TDX support
+==============================
+Because shared EPT is the same as the existing EPT, use the existing logic for
+shared EPT. On the other hand, secure EPT requires additional operations
+instead of directly reading/writing of the EPT entry.
+
+On EPT violation, The KVM mmu walks down the EPT tree from the root, determines
+the EPT entry to operate, and updates the entry. If necessary, a TLB shootdown
+is done. Because it's very slow to directly walk secure EPT by TDX SEAMCALL,
+TDH.MEM.SEPT.RD(), the mirror of secure EPT is created and maintained. Add
+hooks to KVM MMU to reuse the existing code.
+
+EPT violation on shared GPA
+---------------------------
+(1) EPT violation on shared GPA or zapping shared GPA
+ ::
+
+ walk down shared EPT tree (the existing code)
+ |
+ |
+ V
+ shared EPT tree (CPU refers.)
+
+(2) update the EPT entry. (the existing code)
+
+ TLB shootdown in the case of zapping.
+
+
+EPT violation on private GPA
+----------------------------
+(1) EPT violation on private GPA or zapping private GPA
+ ::
+
+ walk down the mirror of secure EPT tree (mostly same as the existing code)
+ |
+ |
+ V
+ mirror of secure EPT tree (KVM MMU software only. reuse of the existing code)
+
+(2) update the (mirrored) EPT entry. (mostly same as the existing code)
+
+(3) call the hooks with what EPT entry is changed
+ ::
+
+ |
+ NEW: hooks in KVM MMU
+ |
+ V
+ secure EPT root(CPU refers)
+
+(4) the TDX backend calls necessary TDX SEAMCALLs to update real secure EPT.
+
+The major modification is to add hooks for the TDX backend for additional
+operations and to pass down which EPT, shared EPT, or private EPT is used, and
+twist the behavior if we're operating on private EPT.
+
+The following depicts the relationship.
+::
+
+ KVM | TDX module
+ | | |
+ -------------+---------- | |
+ | | | |
+ V V | |
+ shared GPA private GPA | |
+ CPU shared EPT pointer KVM private EPT pointer | CPU secure EPT pointer
+ | | | |
+ | | | |
+ V V | V
+ shared EPT private EPT<-------mirror----->Secure EPT
+ | | | |
+ | \--------------------+------\ |
+ | | | |
+ V | V V
+ shared guest page | private guest page
+ |
+ |
+ non-encrypted memory | encrypted memory
+ |
+
+shared EPT: CPU and KVM walk with shared GPA
+ Maintained by the existing code
+private EPT: KVM walks with private GPA
+ Maintained by the twisted existing code
+secure EPT: CPU walks with private GPA.
+ Maintained by TDX module with TDX SEAMCALLs via hooks
+
+
+Tracking private EPT page
+=========================
+Shared EPT pages are managed by struct kvm_mmu_page. They are linked in a list
+structure. When necessary, the list is traversed to operate on. Private EPT
+pages have different characteristics. For example, private pages can't be
+swapped out. When shrinking memory, we'd like to traverse only shared EPT pages
+and skip private EPT pages. Likewise, page migration isn't supported for
+private pages (yet). Introduce an additional list to track shared EPT pages and
+track private EPT pages independently.
+
+At the beginning of EPT violation, the fault handler knows fault GPA, thus it
+knows which EPT to operate on, private or shared. If it's private EPT,
+an additional task is done. Something like "if (private) { callback a hook }".
+Since the fault handler has deep function calls, it's cumbersome to hold the
+information of which EPT is operating. Options to mitigate it are
+
+1. Pass the information as an argument for the function call.
+2. Record the information in struct kvm_mmu_page somehow.
+3. Record the information in vcpu structure.
+
+Option 2 was chosen. Because option 1 requires modifying all the functions. It
+would affect badly to the normal case. Option 3 doesn't work well because in
+some cases, we need to walk both private and shared EPT.
+
+The role of the EPT page can be utilized and one bit can be curved out from
+unused bits in struct kvm_mmu_page_role. When allocating the EPT page,
+initialize the information. Mostly struct kvm_mmu_page is available because
+we're operating on EPT pages.
+
+
+The conversion of private GPA and shared GPA
+============================================
+A page of a given GPA can be assigned to only private GPA xor shared GPA at one
+time. The GPA can't be accessed simultaneously via both private GPA and shared
+GPA. On guest startup, all the GPAs are assigned as private. Guest converts
+the range of GPA to shared (or private) from private (or shared) by MapGPA
+hypercall. MapGPA hypercall takes the start GPA and the size of the region. If
+the given start GPA is shared, VMM converts the region into shared (if it's
+already shared, nop). If the start GPA is private, VMM converts the region into
+private. It implies the guest won't access the unmapped region. private(or
+shared) region after converting to shared(or private).
+
+If the guest TD triggers an EPT violation on the already converted region, the
+access won't be allowed (loop in EPT violation) until other vcpu converts back
+the region.
+
+KVM MMU records which GPA is allowed to access, private or shared by xarray.
+
+
+The original TDP MMU and race condition
+=======================================
+Because vcpus share the EPT, once the EPT entry is zapped, we need to shootdown
+TLB. Send IPI to remote vcpus. Remote vcpus flush their down TLBs. Until TLB
+shootdown is done, vcpus may reference the zapped guest page.
+
+TDP MMU uses read lock of mmu_lock to mitigate vcpu contention. When read lock
+is obtained, it depends on the atomic update of the EPT entry. (On the other
+hand legacy MMU uses write lock.) When vcpu is populating/zapping the EPT entry
+with a read lock held, other vcpu may be populating or zapping the same EPT
+entry at the same time.
+
+To avoid the race condition, the entry is frozen. It means the EPT entry is set
+to the special value, REMOVED_SPTE which clears the present bit. And then after
+TLB shootdown, update the EPT entry to the final value.
+
+Concurrent zapping
+------------------
+1. read lock
+2. freeze the EPT entry (atomically set the value to REMOVED_SPTE)
+ If other vcpu froze the entry, restart page fault.
+3. TLB shootdown
+
+ * send IPI to remote vcpus
+ * TLB flush (local and remote)
+
+ For each entry update, TLB shootdown is needed because of the
+ concurrency.
+4. atomically set the EPT entry to the final value
+5. read unlock
+
+Concurrent populating
+---------------------
+In the case of populating the non-present EPT entry, atomically update the EPT
+entry.
+
+1. read lock
+
+2. atomically update the EPT entry
+ If other vcpu frozen the entry or updated the entry, restart page fault.
+
+3. read unlock
+
+In the case of updating the present EPT entry (e.g. page migration), the
+operation is split into two. Zapping the entry and populating the entry.
+
+1. read lock
+2. zap the EPT entry. follow the concurrent zapping case.
+3. populate the non-present EPT entry.
+4. read unlock
+
+Non-concurrent batched zapping
+------------------------------
+In some cases, zapping the ranges is done exclusively with a write lock held.
+In this case, the TLB shootdown is batched into one.
+
+1. write lock
+2. zap the EPT entries by traversing them
+3. TLB shootdown
+4. write unlock
+
+For Secure EPT, TDX SEAMCALLs are needed in addition to updating the mirrored
+EPT entry.
+
+TDX concurrent zapping
+----------------------
+Add a hook for TDX SEAMCALLs at the step of the TLB shootdown.
+
+1. read lock
+2. freeze the EPT entry(set the value to REMOVED_SPTE)
+3. TLB shootdown via a hook
+
+ * TLB.MEM.RANGE.BLOCK()
+ * TLB.MEM.TRACK()
+ * send IPI to remote vcpus
+
+4. set the EPT entry to the final value
+5. read unlock
+
+TDX concurrent populating
+-------------------------
+TDX SEAMCALLs are required in addition to operating the mirrored EPT entry. The
+frozen entry is utilized by following the zapping case to avoid the race
+condition. A hook can be added.
+
+1. read lock
+2. freeze the EPT entry
+3. hook
+
+ * TDH_MEM_SEPT_ADD() for non-leaf or TDH_MEM_PAGE_AUG() for leaf.
+
+4. set the EPT entry to the final value
+5. read unlock
+
+Without freezing the entry, the following race can happen. Suppose two vcpus
+are faulting on the same GPA and the 2M and 4K level entries aren't populated
+yet.
+
+* vcpu 1: update 2M level EPT entry
+* vcpu 2: update 4K level EPT entry
+* vcpu 2: TDX SEAMCALL to update 4K secure EPT entry => error
+* vcpu 1: TDX SEAMCALL to update 2M secure EPT entry
+
+
+TDX non-concurrent batched zapping
+----------------------------------
+For simplicity, the procedure of concurrent populating is utilized. The
+procedure can be optimized later.
+
+
+Co-existing with unmapping guest private memory
+===============================================
+TODO. This needs to be addressed.
+
+
+Restrictions or future work
+===========================
+The following features aren't supported yet at the moment.
+
+* optimizing non-concurrent zap
+* Large page
+* Page migration
--
2.25.1
From: Isaku Yamahata <[email protected]>
Some of TDG.VP.VMCALL require device model, for example, qemu, to handle
them on behalf of kvm kernel module.
Introduce new kvm exit, KVM_EXIT_TDX, and functions to setup it.
TDG_VP_VMCALL_INVALID_OPERAND is set as default return value to avoid
random value. Device model should update R10 if necessary.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 93 +++++++++++++++++++++++++++++++++++++++-
include/uapi/linux/kvm.h | 57 ++++++++++++++++++++++++
2 files changed, 148 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 12af9a763ff4..0ee5f547d826 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -123,6 +123,18 @@ BUILD_TDVMCALL_ACCESSORS(a1, r13);
BUILD_TDVMCALL_ACCESSORS(a2, r14);
BUILD_TDVMCALL_ACCESSORS(a3, r15);
+#define TDX_VMCALL_REG_MASK_RBX BIT_ULL(2)
+#define TDX_VMCALL_REG_MASK_RDX BIT_ULL(3)
+#define TDX_VMCALL_REG_MASK_RBP BIT_ULL(5)
+#define TDX_VMCALL_REG_MASK_RSI BIT_ULL(6)
+#define TDX_VMCALL_REG_MASK_RDI BIT_ULL(7)
+#define TDX_VMCALL_REG_MASK_R8 BIT_ULL(8)
+#define TDX_VMCALL_REG_MASK_R9 BIT_ULL(9)
+#define TDX_VMCALL_REG_MASK_R12 BIT_ULL(12)
+#define TDX_VMCALL_REG_MASK_R13 BIT_ULL(13)
+#define TDX_VMCALL_REG_MASK_R14 BIT_ULL(14)
+#define TDX_VMCALL_REG_MASK_R15 BIT_ULL(15)
+
static __always_inline unsigned long tdvmcall_exit_type(struct kvm_vcpu *vcpu)
{
return kvm_r10_read(vcpu);
@@ -872,6 +884,80 @@ static int tdx_emulate_vmcall(struct kvm_vcpu *vcpu)
return 1;
}
+static int tdx_complete_vp_vmcall(struct kvm_vcpu *vcpu)
+{
+ struct kvm_tdx_vmcall *tdx_vmcall = &vcpu->run->tdx.u.vmcall;
+ __u64 reg_mask;
+
+ tdvmcall_set_return_code(vcpu, tdx_vmcall->status_code);
+ tdvmcall_set_return_val(vcpu, tdx_vmcall->out_r11);
+
+ reg_mask = kvm_rcx_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R12)
+ kvm_r12_write(vcpu, tdx_vmcall->out_r12);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R13)
+ kvm_r13_write(vcpu, tdx_vmcall->out_r13);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R14)
+ kvm_r14_write(vcpu, tdx_vmcall->out_r14);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R15)
+ kvm_r15_write(vcpu, tdx_vmcall->out_r15);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RBX)
+ kvm_rbx_write(vcpu, tdx_vmcall->out_rbx);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RDI)
+ kvm_rdi_write(vcpu, tdx_vmcall->out_rdi);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RSI)
+ kvm_rsi_write(vcpu, tdx_vmcall->out_rsi);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R8)
+ kvm_r8_write(vcpu, tdx_vmcall->out_r8);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R9)
+ kvm_r9_write(vcpu, tdx_vmcall->out_r9);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RDX)
+ kvm_rdx_write(vcpu, tdx_vmcall->out_rdx);
+
+ return 1;
+}
+
+static int tdx_vp_vmcall_to_user(struct kvm_vcpu *vcpu)
+{
+ struct kvm_tdx_vmcall *tdx_vmcall = &vcpu->run->tdx.u.vmcall;
+ __u64 reg_mask;
+
+ vcpu->arch.complete_userspace_io = tdx_complete_vp_vmcall;
+ memset(tdx_vmcall, 0, sizeof(*tdx_vmcall));
+
+ vcpu->run->exit_reason = KVM_EXIT_TDX;
+ vcpu->run->tdx.type = KVM_EXIT_TDX_VMCALL;
+ tdx_vmcall->type = tdvmcall_exit_type(vcpu);
+ tdx_vmcall->subfunction = tdvmcall_leaf(vcpu);
+ tdx_vmcall->status_code = TDG_VP_VMCALL_INVALID_OPERAND;
+
+ reg_mask = kvm_rcx_read(vcpu);
+ tdx_vmcall->reg_mask = reg_mask;
+ if (reg_mask & TDX_VMCALL_REG_MASK_R12)
+ tdx_vmcall->in_r12 = kvm_r12_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R13)
+ tdx_vmcall->in_r13 = kvm_r13_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R14)
+ tdx_vmcall->in_r14 = kvm_r14_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R15)
+ tdx_vmcall->in_r15 = kvm_r15_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RBX)
+ tdx_vmcall->in_rbx = kvm_rbx_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RDI)
+ tdx_vmcall->in_rdi = kvm_rdi_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RSI)
+ tdx_vmcall->in_rsi = kvm_rsi_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R8)
+ tdx_vmcall->in_r8 = kvm_r8_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_R9)
+ tdx_vmcall->in_r9 = kvm_r9_read(vcpu);
+ if (reg_mask & TDX_VMCALL_REG_MASK_RDX)
+ tdx_vmcall->in_rdx = kvm_rdx_read(vcpu);
+
+ /* notify userspace to handle the request */
+ return 0;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -882,8 +968,11 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
break;
}
- tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
- return 1;
+ /*
+ * Unknown VMCALL. Toss the request to the user space as it may know
+ * how to handle.
+ */
+ return tdx_vp_vmcall_to_user(vcpu);
}
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 6bc142678b03..ebb4328d5080 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -237,6 +237,60 @@ struct kvm_xen_exit {
} u;
};
+struct kvm_tdx_exit {
+#define KVM_EXIT_TDX_VMCALL 1
+ __u32 type;
+ __u32 pad;
+
+ union {
+ struct kvm_tdx_vmcall {
+ /*
+ * Guest-Host-Communication Interface for TDX spec
+ * defines the ABI for TDG.VP.VMCALL.
+ */
+
+ /* Input parameters: guest -> VMM */
+ __u64 type; /* r10 */
+ __u64 subfunction; /* r11 */
+ __u64 reg_mask; /* rcx */
+ /*
+ * Subfunction specific.
+ * Registers are used in this order to pass input
+ * arguments. r12=arg0, r13=arg1, etc.
+ */
+ __u64 in_r12;
+ __u64 in_r13;
+ __u64 in_r14;
+ __u64 in_r15;
+ __u64 in_rbx;
+ __u64 in_rdi;
+ __u64 in_rsi;
+ __u64 in_r8;
+ __u64 in_r9;
+ __u64 in_rdx;
+
+ /* Output parameters: VMM -> guest */
+ __u64 status_code; /* r10 */
+ /*
+ * Subfunction specific.
+ * Registers are used in this order to output return
+ * values. r11=ret0, r12=ret1, etc.
+ */
+ __u64 out_r11;
+ __u64 out_r12;
+ __u64 out_r13;
+ __u64 out_r14;
+ __u64 out_r15;
+ __u64 out_rbx;
+ __u64 out_rdi;
+ __u64 out_rsi;
+ __u64 out_r8;
+ __u64 out_r9;
+ __u64 out_rdx;
+ } vmcall;
+ } u;
+};
+
#define KVM_S390_GET_SKEYS_NONE 1
#define KVM_S390_SKEYS_MAX 1048576
@@ -279,6 +333,7 @@ struct kvm_xen_exit {
#define KVM_EXIT_RISCV_CSR 36
#define KVM_EXIT_NOTIFY 37
#define KVM_EXIT_MEMORY_FAULT 38
+#define KVM_EXIT_TDX 39
/* For KVM_EXIT_INTERNAL_ERROR */
/* Emulate instruction failed. */
@@ -527,6 +582,8 @@ struct kvm_run {
__u64 gpa;
__u64 size;
} memory;
+ /* KVM_EXIT_TDX_VMCALL */
+ struct kvm_tdx_exit tdx;
/* Fix the size of the union. */
char padding[256];
};
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up TDX PV map_gpa hypercall to the kvm/mmu backend.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 0c6386fe4684..853cfda99fed 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1216,6 +1216,24 @@ static int tdx_emulate_wrmsr(struct kvm_vcpu *vcpu)
return 1;
}
+static int tdx_map_gpa(struct kvm_vcpu *vcpu)
+{
+ struct kvm *kvm = vcpu->kvm;
+ gpa_t gpa = tdvmcall_a0_read(vcpu);
+ gpa_t size = tdvmcall_a1_read(vcpu);
+ gpa_t end = gpa + size;
+
+ if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
+ end < gpa ||
+ end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
+ kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+ }
+
+ return tdx_vp_vmcall_to_user(vcpu);
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -1241,6 +1259,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
* guest TD doesn't make sense. No argument check is done.
*/
return tdx_vp_vmcall_to_user(vcpu);
+ case TDG_VP_VMCALL_MAP_GPA:
+ return tdx_map_gpa(vcpu);
default:
break;
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up TDX PV report fatal error hypercall to exit to device model so that
it can gracefully handle it.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 25332290c268..0c6386fe4684 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1234,6 +1234,13 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
return tdx_emulate_rdmsr(vcpu);
case EXIT_REASON_MSR_WRITE:
return tdx_emulate_wrmsr(vcpu);
+ case TDG_VP_VMCALL_REPORT_FATAL_ERROR:
+ /*
+ * Exit to userspace device model for tear down.
+ * Because guest TD is already panicking, returning an error to
+ * guest TD doesn't make sense. No argument check is done.
+ */
+ return tdx_vp_vmcall_to_user(vcpu);
default:
break;
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because guest TD memory is protected, VMM patching guest binary for
hypercall instruction isn't possible. Add a method to ignore hypercall
patching with a warning. Note: guest TD kernel needs to be modified to use
TDG.VP.VMCALL for hypercall.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index dfa072253397..21aebf38697a 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -725,6 +725,19 @@ static u32 vt_get_interrupt_shadow(struct kvm_vcpu *vcpu)
return vmx_get_interrupt_shadow(vcpu);
}
+static void vt_patch_hypercall(struct kvm_vcpu *vcpu,
+ unsigned char *hypercall)
+{
+ /*
+ * Because guest memory is protected, guest can't be patched. TD kernel
+ * is modified to use TDG.VP.VMCAL for hypercall.
+ */
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return;
+
+ vmx_patch_hypercall(vcpu, hypercall);
+}
+
static void vt_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
{
if (is_td_vcpu(vcpu))
@@ -994,7 +1007,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.update_emulated_instruction = vmx_update_emulated_instruction,
.set_interrupt_shadow = vt_set_interrupt_shadow,
.get_interrupt_shadow = vt_get_interrupt_shadow,
- .patch_hypercall = vmx_patch_hypercall,
+ .patch_hypercall = vt_patch_hypercall,
.inject_irq = vt_inject_irq,
.inject_nmi = vt_inject_nmi,
.inject_exception = vt_inject_exception,
--
2.25.1
From: Sean Christopherson <[email protected]>
TDX protects TDX guest state from VMM. Implement access methods for TDX
guest state to ignore them or return zero. Because those methods can be
called by kvm ioctls to set/get cpu registers, they don't have KVM_BUG_ON
except one method.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 269 +++++++++++++++++++++++++++++++++----
arch/x86/kvm/vmx/tdx.c | 49 ++++++-
arch/x86/kvm/vmx/x86_ops.h | 13 ++
3 files changed, 304 insertions(+), 27 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 73d330488bfe..07dfbf9a8b23 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -387,6 +387,184 @@ static void vt_vcpu_deliver_init(struct kvm_vcpu *vcpu)
kvm_vcpu_deliver_init(vcpu);
}
+static void vt_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_vcpu_after_set_cpuid(vcpu);
+}
+
+static void vt_update_exception_bitmap(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_update_exception_bitmap(vcpu);
+}
+
+static u64 vt_get_segment_base(struct kvm_vcpu *vcpu, int seg)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_get_segment_base(vcpu, seg);
+
+ return vmx_get_segment_base(vcpu, seg);
+}
+
+static void vt_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var,
+ int seg)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_get_segment(vcpu, var, seg);
+ return;
+ }
+
+ vmx_get_segment(vcpu, var, seg);
+}
+
+static void vt_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var,
+ int seg)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_segment(vcpu, var, seg);
+}
+
+static int vt_get_cpl(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_get_cpl(vcpu);
+
+ return vmx_get_cpl(vcpu);
+}
+
+static void vt_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
+{
+ if (is_td_vcpu(vcpu)) {
+ *db = 0;
+ *l = 0;
+ return;
+ }
+
+ vmx_get_cs_db_l_bits(vcpu, db, l);
+}
+
+static void vt_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_cr0(vcpu, cr0);
+}
+
+static void vt_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_cr4(vcpu, cr4);
+}
+
+static int vt_set_efer(struct kvm_vcpu *vcpu, u64 efer)
+{
+ if (is_td_vcpu(vcpu))
+ return 0;
+
+ return vmx_set_efer(vcpu, efer);
+}
+
+static void vt_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+{
+ if (is_td_vcpu(vcpu)) {
+ memset(dt, 0, sizeof(*dt));
+ return;
+ }
+
+ vmx_get_idt(vcpu, dt);
+}
+
+static void vt_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_idt(vcpu, dt);
+}
+
+static void vt_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+{
+ if (is_td_vcpu(vcpu)) {
+ memset(dt, 0, sizeof(*dt));
+ return;
+ }
+
+ vmx_get_gdt(vcpu, dt);
+}
+
+static void vt_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_gdt(vcpu, dt);
+}
+
+static void vt_set_dr7(struct kvm_vcpu *vcpu, unsigned long val)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_dr7(vcpu, val);
+}
+
+static void vt_sync_dirty_debug_regs(struct kvm_vcpu *vcpu)
+{
+ /*
+ * MOV-DR exiting is always cleared for TD guest, even in debug mode.
+ * Thus KVM_DEBUGREG_WONT_EXIT can never be set and it should never
+ * reach here for TD vcpu.
+ */
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return;
+
+ vmx_sync_dirty_debug_regs(vcpu);
+}
+
+static void vt_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_cache_reg(vcpu, reg);
+ return;
+ }
+
+ vmx_cache_reg(vcpu, reg);
+}
+
+static unsigned long vt_get_rflags(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_get_rflags(vcpu);
+
+ return vmx_get_rflags(vcpu);
+}
+
+static void vt_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_rflags(vcpu, rflags);
+}
+
+static bool vt_get_if_flag(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return false;
+
+ return vmx_get_if_flag(vcpu);
+}
+
static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu)) {
@@ -531,6 +709,14 @@ static void vt_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
vmx_inject_irq(vcpu, reinjected);
}
+static void vt_inject_exception(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_inject_exception(vcpu);
+}
+
static void vt_cancel_injection(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu))
@@ -577,6 +763,39 @@ static void vt_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
vmx_get_exit_info(vcpu, reason, info1, info2, intr_info, error_code);
}
+
+static void vt_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_update_cr8_intercept(vcpu, tpr, irr);
+}
+
+static void vt_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_load_eoi_exitmap(vcpu, eoi_exit_bitmap);
+}
+
+static int vt_set_tss_addr(struct kvm *kvm, unsigned int addr)
+{
+ if (is_td(kvm))
+ return 0;
+
+ return vmx_set_tss_addr(kvm, addr);
+}
+
+static int vt_set_identity_map_addr(struct kvm *kvm, u64 ident_addr)
+{
+ if (is_td(kvm))
+ return 0;
+
+ return vmx_set_identity_map_addr(kvm, ident_addr);
+}
+
static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
if (is_td_vcpu(vcpu))
@@ -642,29 +861,29 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.vcpu_load = vt_vcpu_load,
.vcpu_put = vt_vcpu_put,
- .update_exception_bitmap = vmx_update_exception_bitmap,
+ .update_exception_bitmap = vt_update_exception_bitmap,
.get_msr_feature = vmx_get_msr_feature,
.get_msr = vt_get_msr,
.set_msr = vt_set_msr,
- .get_segment_base = vmx_get_segment_base,
- .get_segment = vmx_get_segment,
- .set_segment = vmx_set_segment,
- .get_cpl = vmx_get_cpl,
- .get_cs_db_l_bits = vmx_get_cs_db_l_bits,
- .set_cr0 = vmx_set_cr0,
+ .get_segment_base = vt_get_segment_base,
+ .get_segment = vt_get_segment,
+ .set_segment = vt_set_segment,
+ .get_cpl = vt_get_cpl,
+ .get_cs_db_l_bits = vt_get_cs_db_l_bits,
+ .set_cr0 = vt_set_cr0,
.is_valid_cr4 = vmx_is_valid_cr4,
- .set_cr4 = vmx_set_cr4,
- .set_efer = vmx_set_efer,
- .get_idt = vmx_get_idt,
- .set_idt = vmx_set_idt,
- .get_gdt = vmx_get_gdt,
- .set_gdt = vmx_set_gdt,
- .set_dr7 = vmx_set_dr7,
- .sync_dirty_debug_regs = vmx_sync_dirty_debug_regs,
- .cache_reg = vmx_cache_reg,
- .get_rflags = vmx_get_rflags,
- .set_rflags = vmx_set_rflags,
- .get_if_flag = vmx_get_if_flag,
+ .set_cr4 = vt_set_cr4,
+ .set_efer = vt_set_efer,
+ .get_idt = vt_get_idt,
+ .set_idt = vt_set_idt,
+ .get_gdt = vt_get_gdt,
+ .set_gdt = vt_set_gdt,
+ .set_dr7 = vt_set_dr7,
+ .sync_dirty_debug_regs = vt_sync_dirty_debug_regs,
+ .cache_reg = vt_cache_reg,
+ .get_rflags = vt_get_rflags,
+ .set_rflags = vt_set_rflags,
+ .get_if_flag = vt_get_if_flag,
.flush_tlb_all = vt_flush_tlb_all,
.flush_tlb_current = vt_flush_tlb_current,
@@ -681,7 +900,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.patch_hypercall = vmx_patch_hypercall,
.inject_irq = vt_inject_irq,
.inject_nmi = vt_inject_nmi,
- .inject_exception = vmx_inject_exception,
+ .inject_exception = vt_inject_exception,
.cancel_injection = vt_cancel_injection,
.interrupt_allowed = vt_interrupt_allowed,
.nmi_allowed = vt_nmi_allowed,
@@ -689,11 +908,11 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.set_nmi_mask = vt_set_nmi_mask,
.enable_nmi_window = vt_enable_nmi_window,
.enable_irq_window = vt_enable_irq_window,
- .update_cr8_intercept = vmx_update_cr8_intercept,
+ .update_cr8_intercept = vt_update_cr8_intercept,
.set_virtual_apic_mode = vmx_set_virtual_apic_mode,
.set_apic_access_page_addr = vmx_set_apic_access_page_addr,
.refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
- .load_eoi_exitmap = vmx_load_eoi_exitmap,
+ .load_eoi_exitmap = vt_load_eoi_exitmap,
.apicv_post_state_restore = vt_apicv_post_state_restore,
.required_apicv_inhibits = VMX_REQUIRED_APICV_INHIBITS,
.hwapic_irr_update = vmx_hwapic_irr_update,
@@ -704,13 +923,13 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,
.protected_apic_has_interrupt = vt_protected_apic_has_interrupt,
- .set_tss_addr = vmx_set_tss_addr,
- .set_identity_map_addr = vmx_set_identity_map_addr,
+ .set_tss_addr = vt_set_tss_addr,
+ .set_identity_map_addr = vt_set_identity_map_addr,
.get_mt_mask = vt_get_mt_mask,
.get_exit_info = vt_get_exit_info,
- .vcpu_after_set_cpuid = vmx_vcpu_after_set_cpuid,
+ .vcpu_after_set_cpuid = vt_vcpu_after_set_cpuid,
.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 098e87e7e507..23a184d5ab47 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -3,6 +3,7 @@
#include <linux/mmu_context.h>
#include <asm/fpu/xcr.h>
+#include <asm/virtext.h>
#include <asm/tdx.h>
#include "capabilities.h"
@@ -592,8 +593,15 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
vcpu->arch.tsc_offset = to_kvm_tdx(vcpu->kvm)->tsc_offset;
vcpu->arch.l1_tsc_offset = vcpu->arch.tsc_offset;
- vcpu->arch.guest_state_protected =
- !(to_kvm_tdx(vcpu->kvm)->attributes & TDX_TD_ATTRIBUTE_DEBUG);
+ /*
+ * TODO: support off-TD debug. If TD DEBUG is enabled, guest state
+ * can be accessed. guest_state_protected = false. and kvm ioctl to
+ * access CPU states should be usable for user space VMM (e.g. qemu).
+ *
+ * vcpu->arch.guest_state_protected =
+ * !(to_kvm_tdx(vcpu->kvm)->attributes & TDX_TD_ATTRIBUTE_DEBUG);
+ */
+ vcpu->arch.guest_state_protected = true;
tdx->pi_desc.nv = POSTED_INTR_VECTOR;
tdx->pi_desc.sn = 1;
@@ -1858,6 +1866,43 @@ void tdx_enable_smi_window(struct kvm_vcpu *vcpu)
}
#endif
+int tdx_get_cpl(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+void tdx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg)
+{
+ kvm_register_mark_available(vcpu, reg);
+ switch (reg) {
+ case VCPU_REGS_RSP:
+ case VCPU_REGS_RIP:
+ case VCPU_EXREG_PDPTR:
+ case VCPU_EXREG_CR0:
+ case VCPU_EXREG_CR3:
+ case VCPU_EXREG_CR4:
+ break;
+ default:
+ KVM_BUG_ON(1, vcpu->kvm);
+ break;
+ }
+}
+
+unsigned long tdx_get_rflags(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+u64 tdx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
+{
+ return 0;
+}
+
+void tdx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg)
+{
+ memset(var, 0, sizeof(*var));
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 59d74f4a4b63..9be0ac32d2b4 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -175,6 +175,12 @@ bool tdx_has_emulated_msr(u32 index, bool write);
int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
+int tdx_get_cpl(struct kvm_vcpu *vcpu);
+void tdx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg);
+unsigned long tdx_get_rflags(struct kvm_vcpu *vcpu);
+u64 tdx_get_segment_base(struct kvm_vcpu *vcpu, int seg);
+void tdx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
+
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
void tdx_flush_tlb(struct kvm_vcpu *vcpu);
@@ -220,6 +226,13 @@ static inline bool tdx_has_emulated_msr(u32 index, bool write) { return false; }
static inline int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) { return 1; }
static inline int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) { return 1; }
+static inline int tdx_get_cpl(struct kvm_vcpu *vcpu) { return 0; }
+static inline void tdx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg) {}
+static inline unsigned long tdx_get_rflags(struct kvm_vcpu *vcpu) { return 0; }
+static inline u64 tdx_get_segment_base(struct kvm_vcpu *vcpu, int seg) { return 0; }
+static inline void tdx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var,
+ int seg) {}
+
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
static inline void tdx_flush_tlb(struct kvm_vcpu *vcpu) {}
--
2.25.1
From: Isaku Yamahata <[email protected]>
If the control reaches EXIT_REASON_OTHER_SMI, #SMI is delivered and
handled right after returning from the TDX module to KVM nothing needs to
be done in KVM. Continue TDX vcpu execution.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/include/uapi/asm/vmx.h | 1 +
arch/x86/kvm/vmx/tdx.c | 7 +++++++
2 files changed, 8 insertions(+)
diff --git a/arch/x86/include/uapi/asm/vmx.h b/arch/x86/include/uapi/asm/vmx.h
index a5faf6d88f1b..b3a30ef3efdd 100644
--- a/arch/x86/include/uapi/asm/vmx.h
+++ b/arch/x86/include/uapi/asm/vmx.h
@@ -34,6 +34,7 @@
#define EXIT_REASON_TRIPLE_FAULT 2
#define EXIT_REASON_INIT_SIGNAL 3
#define EXIT_REASON_SIPI_SIGNAL 4
+#define EXIT_REASON_OTHER_SMI 6
#define EXIT_REASON_INTERRUPT_WINDOW 7
#define EXIT_REASON_NMI_WINDOW 8
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 7e0fc3d5f513..ab4e030b8323 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1163,6 +1163,13 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
WARN_ON_ONCE(fastpath != EXIT_FASTPATH_NONE);
switch (exit_reason.basic) {
+ case EXIT_REASON_OTHER_SMI:
+ /*
+ * If reach here, it's not a Machine Check System Management
+ * Interrupt(MSMI). #SMI is delivered and handled right after
+ * SEAMRET, nothing needs to be done in KVM.
+ */
+ return 1;
default:
break;
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX module has mitigation against zero-step attacks or single-step attacks.
When the TDX module finds repeated EPT violations on the same guest RIP,
i.e. no advance in guest, it starts to suspect the attack. The mitigation
logic on the next entry tries to take the lock of S-EPT. It may result in
an error of TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT. As KVM shouldn't
spuriously zap private S-EPT so that guest can make progress, KVM
shouldn't cause the TDX module to trigger the mitigation. Make
(TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT) on entry KVM bug.
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
- This patch is RFC because this is only lightly tested and stress test
isn't done.
---
arch/x86/kvm/vmx/tdx.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 8e392bc3330b..b668f06bbb64 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1670,8 +1670,20 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
{
union tdx_exit_reason exit_reason = to_tdx(vcpu)->exit_reason;
- /* See the comment of tdh_sept_seamcall(). */
- if (unlikely(exit_reason.full == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT)))
+ /*
+ * See the comment of tdh_sept_seamcall().
+ * TDX module has mitigation against zero-step attacks or single-step
+ * attacks. When the TDX module finds repeated EPT violations on the
+ * same guest RIP, i.e. no advance in guest, it starts to suspect the
+ * attack. The mitigation logic on the next entry tries to take the
+ * lock of S-EPT. It may result in an error of (TDX_OPERAND_BUSY |
+ * TDX_OPERAND_ID_SEPT). As KVM shouldn't spuriously zap private S-EPT
+ * so that guest can make progress, KVM shouldn't cause the TDX module
+ * to trigger the mitigation. Make (TDX_OPERAND_BUSY |
+ * TDX_OPERAND_ID_SEPT) on entry KVM bug.
+ */
+ if (KVM_BUG_ON(exit_reason.full == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_SEPT),
+ vcpu->kvm))
return 1;
if (unlikely(exit_reason.full == TDX_SEAMCALL_UD)) {
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up TDX PV CPUID hypercall to the KVM backend function.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 0ee5f547d826..62cd3e899560 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -958,12 +958,34 @@ static int tdx_vp_vmcall_to_user(struct kvm_vcpu *vcpu)
return 0;
}
+static int tdx_emulate_cpuid(struct kvm_vcpu *vcpu)
+{
+ u32 eax, ebx, ecx, edx;
+
+ /* EAX and ECX for cpuid is stored in R12 and R13. */
+ eax = tdvmcall_a0_read(vcpu);
+ ecx = tdvmcall_a1_read(vcpu);
+
+ kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx, false);
+
+ tdvmcall_a0_write(vcpu, eax);
+ tdvmcall_a1_write(vcpu, ebx);
+ tdvmcall_a2_write(vcpu, ecx);
+ tdvmcall_a3_write(vcpu, edx);
+
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+
+ return 1;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
return tdx_emulate_vmcall(vcpu);
switch (tdvmcall_leaf(vcpu)) {
+ case EXIT_REASON_CPUID:
+ return tdx_emulate_cpuid(vcpu);
default:
break;
}
--
2.25.1
From: Sean Christopherson <[email protected]>
TDX uses different ABI to get information about VM exit. Pass intr_info to
the NMI and INTR handlers instead of pulling it from vcpu_vmx in
preparation for sharing the bulk of the handlers with TDX.
When the guest TD exits to VMM, RAX holds status and exit reason, RCX holds
exit qualification etc rather than the VMCS fields because VMM doesn't have
access to the VMCS. The eventual code will be
VMX:
- get exit reason, intr_info, exit_qualification, and etc from VMCS
- call NMI/INTR handlers (common code)
TDX:
- get exit reason, intr_info, exit_qualification, and etc from guest
registers
- call NMI/INTR handlers (common code)
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/vmx.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index ebf262496f47..bbf286a5c338 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6868,24 +6868,22 @@ static void handle_nm_fault_irqoff(struct kvm_vcpu *vcpu)
rdmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
}
-static void handle_exception_irqoff(struct vcpu_vmx *vmx)
+static void handle_exception_irqoff(struct kvm_vcpu *vcpu, u32 intr_info)
{
- u32 intr_info = vmx_get_intr_info(&vmx->vcpu);
-
/* if exit due to PF check for async PF */
if (is_page_fault(intr_info))
- vmx->vcpu.arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
+ vcpu->arch.apf.host_apf_flags = kvm_read_and_reset_apf_flags();
/* if exit due to NM, handle before interrupts are enabled */
else if (is_nm_fault(intr_info))
- handle_nm_fault_irqoff(&vmx->vcpu);
+ handle_nm_fault_irqoff(vcpu);
/* Handle machine checks before interrupts are enabled */
else if (is_machine_check(intr_info))
kvm_machine_check();
}
-static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu)
+static void handle_external_interrupt_irqoff(struct kvm_vcpu *vcpu,
+ u32 intr_info)
{
- u32 intr_info = vmx_get_intr_info(vcpu);
unsigned int vector = intr_info & INTR_INFO_VECTOR_MASK;
gate_desc *desc = (gate_desc *)host_idt_base + vector;
@@ -6908,9 +6906,9 @@ void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
return;
if (vmx->exit_reason.basic == EXIT_REASON_EXTERNAL_INTERRUPT)
- handle_external_interrupt_irqoff(vcpu);
+ handle_external_interrupt_irqoff(vcpu, vmx_get_intr_info(vcpu));
else if (vmx->exit_reason.basic == EXIT_REASON_EXCEPTION_NMI)
- handle_exception_irqoff(vmx);
+ handle_exception_irqoff(vcpu, vmx_get_intr_info(vcpu));
}
/*
--
2.25.1
From: Isaku Yamahata <[email protected]>
On EPT violation, call a common function, __vmx_handle_ept_violation() to
trigger x86 MMU code. On EPT misconfiguration, exit to ring 3 with
KVM_EXIT_UNKNOWN. because EPT misconfiguration can't happen as MMIO is
trigged by TDG.VP.VMCALL. No point to set a misconfiguration value for the
fast path.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 46 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index ab4e030b8323..b2ea9b2f8e60 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1110,6 +1110,48 @@ void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
__vmx_deliver_posted_interrupt(vcpu, &tdx->pi_desc, vector);
}
+static int tdx_handle_ept_violation(struct kvm_vcpu *vcpu)
+{
+ unsigned long exit_qual;
+
+ if (kvm_is_private_gpa(vcpu->kvm, tdexit_gpa(vcpu))) {
+ /*
+ * Always treat SEPT violations as write faults. Ignore the
+ * EXIT_QUALIFICATION reported by TDX-SEAM for SEPT violations.
+ * TD private pages are always RWX in the SEPT tables,
+ * i.e. they're always mapped writable. Just as importantly,
+ * treating SEPT violations as write faults is necessary to
+ * avoid COW allocations, which will cause TDAUGPAGE failures
+ * due to aliasing a single HPA to multiple GPAs.
+ */
+#define TDX_SEPT_VIOLATION_EXIT_QUAL EPT_VIOLATION_ACC_WRITE
+ exit_qual = TDX_SEPT_VIOLATION_EXIT_QUAL;
+ } else {
+ exit_qual = tdexit_exit_qual(vcpu);
+ if (exit_qual & EPT_VIOLATION_ACC_INSTR) {
+ pr_warn("kvm: TDX instr fetch to shared GPA = 0x%lx @ RIP = 0x%lx\n",
+ tdexit_gpa(vcpu), kvm_rip_read(vcpu));
+ vcpu->run->exit_reason = KVM_EXIT_EXCEPTION;
+ vcpu->run->ex.exception = PF_VECTOR;
+ vcpu->run->ex.error_code = exit_qual;
+ return 0;
+ }
+ }
+
+ trace_kvm_page_fault(vcpu, tdexit_gpa(vcpu), exit_qual);
+ return __vmx_handle_ept_violation(vcpu, tdexit_gpa(vcpu), exit_qual);
+}
+
+static int tdx_handle_ept_misconfig(struct kvm_vcpu *vcpu)
+{
+ WARN_ON_ONCE(1);
+
+ vcpu->run->exit_reason = KVM_EXIT_UNKNOWN;
+ vcpu->run->hw.hardware_exit_reason = EXIT_REASON_EPT_MISCONFIG;
+
+ return 0;
+}
+
int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
{
union tdx_exit_reason exit_reason = to_tdx(vcpu)->exit_reason;
@@ -1163,6 +1205,10 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
WARN_ON_ONCE(fastpath != EXIT_FASTPATH_NONE);
switch (exit_reason.basic) {
+ case EXIT_REASON_EPT_VIOLATION:
+ return tdx_handle_ept_violation(vcpu);
+ case EXIT_REASON_EPT_MISCONFIG:
+ return tdx_handle_ept_misconfig(vcpu);
case EXIT_REASON_OTHER_SMI:
/*
* If reach here, it's not a Machine Check System Management
--
2.25.1
From: Isaku Yamahata <[email protected]>
This empty commit is to mark the end of (the first phase of) patch series
of TDX KVM support.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/index.rst | 1 -
.../virt/kvm/intel-tdx-layer-status.rst | 33 -------------------
2 files changed, 34 deletions(-)
delete mode 100644 Documentation/virt/kvm/intel-tdx-layer-status.rst
diff --git a/Documentation/virt/kvm/index.rst b/Documentation/virt/kvm/index.rst
index 40ffc25f3cd1..eafacbff1f4e 100644
--- a/Documentation/virt/kvm/index.rst
+++ b/Documentation/virt/kvm/index.rst
@@ -22,4 +22,3 @@ KVM
intel-tdx
tdx-tdp-mmu
- intel-tdx-layer-status.rst
diff --git a/Documentation/virt/kvm/intel-tdx-layer-status.rst b/Documentation/virt/kvm/intel-tdx-layer-status.rst
deleted file mode 100644
index 7a16fa284b6f..000000000000
--- a/Documentation/virt/kvm/intel-tdx-layer-status.rst
+++ /dev/null
@@ -1,33 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-===================================
-Intel Trust Dodmain Extensions(TDX)
-===================================
-
-Layer status
-============
-What qemu can do
-----------------
-- TDX VM TYPE is exposed to Qemu.
-- Qemu can create/destroy guest of TDX vm type.
-- Qemu can create/destroy vcpu of TDX vm type.
-- Qemu can populate initial guest memory image.
-- Qemu can finalize guest TD.
-- Qemu can start to run vcpu. But vcpu can not make progress yet.
-
-Patch Layer status
-------------------
- Patch layer Status
-
-* TDX, VMX coexistence: Applied
-* TDX architectural definitions: Applied
-* TD VM creation/destruction: Applied
-* TD vcpu creation/destruction: Applied
-* TDX EPT violation: Applied
-* TD finalization: Applied
-* TD vcpu enter/exit: Applied
-* TD vcpu interrupts/exit/hypercall: Not yet
-
-* KVM MMU GPA shared bits: Applied
-* KVM TDP refactoring for TDX: Applied
-* KVM TDP MMU hooks: Applied
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up TDX PV rdmsr/wrmsr hypercall to the KVM backend function.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 39 +++++++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index bb86b850889b..25332290c268 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1181,6 +1181,41 @@ static int tdx_emulate_mmio(struct kvm_vcpu *vcpu)
return 1;
}
+static int tdx_emulate_rdmsr(struct kvm_vcpu *vcpu)
+{
+ u32 index = tdvmcall_a0_read(vcpu);
+ u64 data;
+
+ if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_READ) ||
+ kvm_get_msr(vcpu, index, &data)) {
+ trace_kvm_msr_read_ex(index);
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+ }
+ trace_kvm_msr_read(index, data);
+
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ tdvmcall_set_return_val(vcpu, data);
+ return 1;
+}
+
+static int tdx_emulate_wrmsr(struct kvm_vcpu *vcpu)
+{
+ u32 index = tdvmcall_a0_read(vcpu);
+ u64 data = tdvmcall_a1_read(vcpu);
+
+ if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_WRITE) ||
+ kvm_set_msr(vcpu, index, data)) {
+ trace_kvm_msr_write_ex(index, data);
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+ }
+
+ trace_kvm_msr_write(index, data);
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ return 1;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -1195,6 +1230,10 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
return tdx_emulate_io(vcpu);
case EXIT_REASON_EPT_VIOLATION:
return tdx_emulate_mmio(vcpu);
+ case EXIT_REASON_MSR_READ:
+ return tdx_emulate_rdmsr(vcpu);
+ case EXIT_REASON_MSR_WRITE:
+ return tdx_emulate_wrmsr(vcpu);
default:
break;
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because vmx_set_mce function is VMX specific and it cannot be used for TDX.
Add vt stub to ignore setting up mce for TDX.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 6ec7b6e5b9c2..dfa072253397 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -893,6 +893,14 @@ static void vt_cancel_hv_timer(struct kvm_vcpu *vcpu)
}
#endif
+static void vt_setup_mce(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_setup_mce(vcpu);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -1049,7 +1057,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.cancel_hv_timer = vt_cancel_hv_timer,
#endif
- .setup_mce = vmx_setup_mce,
+ .setup_mce = vt_setup_mce,
#ifdef CONFIG_KVM_SMM
.smi_allowed = vt_smi_allowed,
--
2.25.1
From: Isaku Yamahata <[email protected]>
Because guest TD state is protected, exceptions in guest TDs can't be
intercepted. TDX VMM doesn't need to handle exceptions.
tdx_handle_exit_irqoff() handles NMI and machine check. Ignore NMI and
machine check and continue guest TD execution.
For external interrupt, increment stats same to the VMX case.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index b2ea9b2f8e60..f7840232be85 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -777,6 +777,25 @@ void tdx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
tdexit_intr_info(vcpu));
}
+static int tdx_handle_exception(struct kvm_vcpu *vcpu)
+{
+ u32 intr_info = tdexit_intr_info(vcpu);
+
+ if (is_nmi(intr_info) || is_machine_check(intr_info))
+ return 1;
+
+ kvm_pr_unimpl("unexpected exception 0x%x(exit_reason 0x%llx qual 0x%lx)\n",
+ intr_info,
+ to_tdx(vcpu)->exit_reason.full, tdexit_exit_qual(vcpu));
+ return -EFAULT;
+}
+
+static int tdx_handle_external_interrupt(struct kvm_vcpu *vcpu)
+{
+ ++vcpu->stat.irq_exits;
+ return 1;
+}
+
static int tdx_handle_triple_fault(struct kvm_vcpu *vcpu)
{
vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN;
@@ -1205,6 +1224,10 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath)
WARN_ON_ONCE(fastpath != EXIT_FASTPATH_NONE);
switch (exit_reason.basic) {
+ case EXIT_REASON_EXCEPTION_NMI:
+ return tdx_handle_exception(vcpu);
+ case EXIT_REASON_EXTERNAL_INTERRUPT:
+ return tdx_handle_external_interrupt(vcpu);
case EXIT_REASON_EPT_VIOLATION:
return tdx_handle_ept_violation(vcpu);
case EXIT_REASON_EPT_MISCONFIG:
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX vcpu control structure defines one bit for pending NMI for VMM to
inject NMI by setting the bit without knowing TDX vcpu NMI states. Because
the vcpu state is protected, VMM can't know about NMI states of TDX vcpu.
The TDX module handles actual injection and NMI states transition.
Add methods for NMI and treat NMI can be injected always.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/main.c | 64 +++++++++++++++++++++++++++++++++++---
arch/x86/kvm/vmx/tdx.c | 5 +++
arch/x86/kvm/vmx/x86_ops.h | 2 ++
3 files changed, 66 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index a54b97203e5c..c3358cf1c8ef 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -316,6 +316,60 @@ static void vt_flush_tlb_guest(struct kvm_vcpu *vcpu)
vmx_flush_tlb_guest(vcpu);
}
+static void vt_inject_nmi(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ tdx_inject_nmi(vcpu);
+ return;
+ }
+
+ vmx_inject_nmi(vcpu);
+}
+
+static int vt_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+{
+ /*
+ * The TDX module manages NMI windows and NMI reinjection, and hides NMI
+ * blocking, all KVM can do is throw an NMI over the wall.
+ */
+ if (is_td_vcpu(vcpu))
+ return true;
+
+ return vmx_nmi_allowed(vcpu, for_injection);
+}
+
+static bool vt_get_nmi_mask(struct kvm_vcpu *vcpu)
+{
+ /*
+ * Assume NMIs are always unmasked. KVM could query PEND_NMI and treat
+ * NMIs as masked if a previous NMI is still pending, but SEAMCALLs are
+ * expensive and the end result is unchanged as the only relevant usage
+ * of get_nmi_mask() is to limit the number of pending NMIs, i.e. it
+ * only changes whether KVM or the TDX module drops an NMI.
+ */
+ if (is_td_vcpu(vcpu))
+ return false;
+
+ return vmx_get_nmi_mask(vcpu);
+}
+
+static void vt_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_nmi_mask(vcpu, masked);
+}
+
+static void vt_enable_nmi_window(struct kvm_vcpu *vcpu)
+{
+ /* Refer the comment in vt_get_nmi_mask(). */
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_enable_nmi_window(vcpu);
+}
+
static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
int pgd_level)
{
@@ -495,14 +549,14 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.get_interrupt_shadow = vt_get_interrupt_shadow,
.patch_hypercall = vmx_patch_hypercall,
.inject_irq = vt_inject_irq,
- .inject_nmi = vmx_inject_nmi,
+ .inject_nmi = vt_inject_nmi,
.inject_exception = vmx_inject_exception,
.cancel_injection = vt_cancel_injection,
.interrupt_allowed = vt_interrupt_allowed,
- .nmi_allowed = vmx_nmi_allowed,
- .get_nmi_mask = vmx_get_nmi_mask,
- .set_nmi_mask = vmx_set_nmi_mask,
- .enable_nmi_window = vmx_enable_nmi_window,
+ .nmi_allowed = vt_nmi_allowed,
+ .get_nmi_mask = vt_get_nmi_mask,
+ .set_nmi_mask = vt_set_nmi_mask,
+ .enable_nmi_window = vt_enable_nmi_window,
.enable_irq_window = vt_enable_irq_window,
.update_cr8_intercept = vmx_update_cr8_intercept,
.set_virtual_apic_mode = vmx_set_virtual_apic_mode,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index d19e53605f12..44977fd3c0d1 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -740,6 +740,11 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
return EXIT_FASTPATH_NONE;
}
+void tdx_inject_nmi(struct kvm_vcpu *vcpu)
+{
+ td_management_write8(to_tdx(vcpu), TD_VCPU_PEND_NMI, 1);
+}
+
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
{
td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 586478ced9f7..fbbbae685363 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -165,6 +165,7 @@ u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
int trig_mode, int vector);
+void tdx_inject_nmi(struct kvm_vcpu *vcpu);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -201,6 +202,7 @@ static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
static inline void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
int trig_mode, int vector) {}
+static inline void tdx_inject_nmi(struct kvm_vcpu *vcpu) {}
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX protects TDX guest TSC state from VMM. Implement access methods to
ignore guest TSC.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 44 +++++++++++++++++++++++++++++++++++++----
1 file changed, 40 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 32c992b5ab0d..6ec7b6e5b9c2 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -828,6 +828,42 @@ static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
return __vmx_get_mt_mask(vcpu, gfn, is_mmio, true);
}
+static u64 vt_get_l2_tsc_offset(struct kvm_vcpu *vcpu)
+{
+ /* TDX doesn't support L2 guest at the moment. */
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return 0;
+
+ return vmx_get_l2_tsc_offset(vcpu);
+}
+
+static u64 vt_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu)
+{
+ /* TDX doesn't support L2 guest at the moment. */
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return 0;
+
+ return vmx_get_l2_tsc_multiplier(vcpu);
+}
+
+static void vt_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
+{
+ /* In TDX, tsc offset can't be changed. */
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_write_tsc_offset(vcpu, offset);
+}
+
+static void vt_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 multiplier)
+{
+ /* In TDX, tsc multiplier can't be changed. */
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_write_tsc_multiplier(vcpu, multiplier);
+}
+
static void vt_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
{
if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
@@ -986,10 +1022,10 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
- .get_l2_tsc_offset = vmx_get_l2_tsc_offset,
- .get_l2_tsc_multiplier = vmx_get_l2_tsc_multiplier,
- .write_tsc_offset = vmx_write_tsc_offset,
- .write_tsc_multiplier = vmx_write_tsc_multiplier,
+ .get_l2_tsc_offset = vt_get_l2_tsc_offset,
+ .get_l2_tsc_multiplier = vt_get_l2_tsc_multiplier,
+ .write_tsc_offset = vt_write_tsc_offset,
+ .write_tsc_multiplier = vt_write_tsc_multiplier,
.load_mmu_pgd = vt_load_mmu_pgd,
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX supports interrupt inject into vcpu with posted interrupt. Wire up the
corresponding kvm x86 operations to posted interrupt. Move
kvm_vcpu_trigger_posted_interrupt() from vmx.c to common.h to share the
code.
VMX can inject interrupt by setting interrupt information field,
VM_ENTRY_INTR_INFO_FIELD, of VMCS. TDX supports interrupt injection only
by posted interrupt. Ignore the execution path to access
VM_ENTRY_INTR_INFO_FIELD.
As cpu state is protected and apicv is enabled for the TDX guest, VMM can
inject interrupt by updating posted interrupt descriptor. Treat interrupt
can be injected always.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/common.h | 71 ++++++++++++++++++++++++++
arch/x86/kvm/vmx/main.c | 93 ++++++++++++++++++++++++++++++----
arch/x86/kvm/vmx/posted_intr.c | 2 +-
arch/x86/kvm/vmx/posted_intr.h | 2 +
arch/x86/kvm/vmx/tdx.c | 24 +++++++++
arch/x86/kvm/vmx/vmx.c | 67 +-----------------------
arch/x86/kvm/vmx/x86_ops.h | 7 ++-
7 files changed, 189 insertions(+), 77 deletions(-)
diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
index 422b24af7fc1..39ddead9d2bd 100644
--- a/arch/x86/kvm/vmx/common.h
+++ b/arch/x86/kvm/vmx/common.h
@@ -4,6 +4,7 @@
#include <linux/kvm_host.h>
+#include "posted_intr.h"
#include "mmu.h"
u8 __vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio, bool check_cr0_cd);
@@ -32,4 +33,74 @@ static inline int __vmx_handle_ept_violation(struct kvm_vcpu *vcpu, gpa_t gpa,
return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0);
}
+static inline void kvm_vcpu_trigger_posted_interrupt(struct kvm_vcpu *vcpu,
+ int pi_vec)
+{
+#ifdef CONFIG_SMP
+ if (vcpu->mode == IN_GUEST_MODE) {
+ /*
+ * The vector of the virtual has already been set in the PIR.
+ * Send a notification event to deliver the virtual interrupt
+ * unless the vCPU is the currently running vCPU, i.e. the
+ * event is being sent from a fastpath VM-Exit handler, in
+ * which case the PIR will be synced to the vIRR before
+ * re-entering the guest.
+ *
+ * When the target is not the running vCPU, the following
+ * possibilities emerge:
+ *
+ * Case 1: vCPU stays in non-root mode. Sending a notification
+ * event posts the interrupt to the vCPU.
+ *
+ * Case 2: vCPU exits to root mode and is still runnable. The
+ * PIR will be synced to the vIRR before re-entering the guest.
+ * Sending a notification event is ok as the host IRQ handler
+ * will ignore the spurious event.
+ *
+ * Case 3: vCPU exits to root mode and is blocked. vcpu_block()
+ * has already synced PIR to vIRR and never blocks the vCPU if
+ * the vIRR is not empty. Therefore, a blocked vCPU here does
+ * not wait for any requested interrupts in PIR, and sending a
+ * notification event also results in a benign, spurious event.
+ */
+
+ if (vcpu != kvm_get_running_vcpu())
+ apic->send_IPI_mask(get_cpu_mask(vcpu->cpu), pi_vec);
+ return;
+ }
+#endif
+ /*
+ * The vCPU isn't in the guest; wake the vCPU in case it is blocking,
+ * otherwise do nothing as KVM will grab the highest priority pending
+ * IRQ via ->sync_pir_to_irr() in vcpu_enter_guest().
+ */
+ kvm_vcpu_wake_up(vcpu);
+}
+
+/*
+ * Send interrupt to vcpu via posted interrupt way.
+ * 1. If target vcpu is running(non-root mode), send posted interrupt
+ * notification to vcpu and hardware will sync PIR to vIRR atomically.
+ * 2. If target vcpu isn't running(root mode), kick it to pick up the
+ * interrupt from PIR in next vmentry.
+ */
+static inline void __vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu,
+ struct pi_desc *pi_desc, int vector)
+{
+ if (pi_test_and_set_pir(vector, pi_desc))
+ return;
+
+ /* If a previous notification has sent the IPI, nothing to do. */
+ if (pi_test_and_set_on(pi_desc))
+ return;
+
+ /*
+ * The implied barrier in pi_test_and_set_on() pairs with the smp_mb_*()
+ * after setting vcpu->mode in vcpu_enter_guest(), thus the vCPU is
+ * guaranteed to see PID.ON=1 and sync the PIR to IRR if triggering a
+ * posted interrupt "fails" because vcpu->mode != IN_GUEST_MODE.
+ */
+ kvm_vcpu_trigger_posted_interrupt(vcpu, POSTED_INTR_VECTOR);
+}
+
#endif /* __KVM_X86_VMX_COMMON_H */
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 75d74aa79446..b3c2be3e78ef 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -240,6 +240,34 @@ static bool vt_protected_apic_has_interrupt(struct kvm_vcpu *vcpu)
return tdx_protected_apic_has_interrupt(vcpu);
}
+static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
+{
+ struct pi_desc *pi = vcpu_to_pi_desc(vcpu);
+
+ pi_clear_on(pi);
+ memset(pi->pir, 0, sizeof(pi->pir));
+}
+
+static int vt_sync_pir_to_irr(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return -1;
+
+ return vmx_sync_pir_to_irr(vcpu);
+}
+
+static void vt_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
+ int trig_mode, int vector)
+{
+ if (is_td_vcpu(apic->vcpu)) {
+ tdx_deliver_interrupt(apic, delivery_mode, trig_mode,
+ vector);
+ return;
+ }
+
+ vmx_deliver_interrupt(apic, delivery_mode, trig_mode, vector);
+}
+
static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu)) {
@@ -307,6 +335,53 @@ static void vt_sched_in(struct kvm_vcpu *vcpu, int cpu)
vmx_sched_in(vcpu, cpu);
}
+static void vt_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+ vmx_set_interrupt_shadow(vcpu, mask);
+}
+
+static u32 vt_get_interrupt_shadow(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return 0;
+
+ return vmx_get_interrupt_shadow(vcpu);
+}
+
+static void vt_inject_irq(struct kvm_vcpu *vcpu, bool reinjected)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_inject_irq(vcpu, reinjected);
+}
+
+static void vt_cancel_injection(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_cancel_injection(vcpu);
+}
+
+static int vt_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
+{
+ if (is_td_vcpu(vcpu))
+ return true;
+
+ return vmx_interrupt_allowed(vcpu, for_injection);
+}
+
+static void vt_enable_irq_window(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_enable_irq_window(vcpu);
+}
+
static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
if (is_td_vcpu(vcpu))
@@ -406,31 +481,31 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.handle_exit = vmx_handle_exit,
.skip_emulated_instruction = vmx_skip_emulated_instruction,
.update_emulated_instruction = vmx_update_emulated_instruction,
- .set_interrupt_shadow = vmx_set_interrupt_shadow,
- .get_interrupt_shadow = vmx_get_interrupt_shadow,
+ .set_interrupt_shadow = vt_set_interrupt_shadow,
+ .get_interrupt_shadow = vt_get_interrupt_shadow,
.patch_hypercall = vmx_patch_hypercall,
- .inject_irq = vmx_inject_irq,
+ .inject_irq = vt_inject_irq,
.inject_nmi = vmx_inject_nmi,
.inject_exception = vmx_inject_exception,
- .cancel_injection = vmx_cancel_injection,
- .interrupt_allowed = vmx_interrupt_allowed,
+ .cancel_injection = vt_cancel_injection,
+ .interrupt_allowed = vt_interrupt_allowed,
.nmi_allowed = vmx_nmi_allowed,
.get_nmi_mask = vmx_get_nmi_mask,
.set_nmi_mask = vmx_set_nmi_mask,
.enable_nmi_window = vmx_enable_nmi_window,
- .enable_irq_window = vmx_enable_irq_window,
+ .enable_irq_window = vt_enable_irq_window,
.update_cr8_intercept = vmx_update_cr8_intercept,
.set_virtual_apic_mode = vmx_set_virtual_apic_mode,
.set_apic_access_page_addr = vmx_set_apic_access_page_addr,
.refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
.load_eoi_exitmap = vmx_load_eoi_exitmap,
- .apicv_post_state_restore = vmx_apicv_post_state_restore,
+ .apicv_post_state_restore = vt_apicv_post_state_restore,
.required_apicv_inhibits = VMX_REQUIRED_APICV_INHIBITS,
.hwapic_irr_update = vmx_hwapic_irr_update,
.hwapic_isr_update = vmx_hwapic_isr_update,
.guest_apic_has_interrupt = vmx_guest_apic_has_interrupt,
- .sync_pir_to_irr = vmx_sync_pir_to_irr,
- .deliver_interrupt = vmx_deliver_interrupt,
+ .sync_pir_to_irr = vt_sync_pir_to_irr,
+ .deliver_interrupt = vt_deliver_interrupt,
.dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,
.protected_apic_has_interrupt = vt_protected_apic_has_interrupt,
diff --git a/arch/x86/kvm/vmx/posted_intr.c b/arch/x86/kvm/vmx/posted_intr.c
index 92de016852ca..2b2da6c18504 100644
--- a/arch/x86/kvm/vmx/posted_intr.c
+++ b/arch/x86/kvm/vmx/posted_intr.c
@@ -52,7 +52,7 @@ static inline struct vcpu_pi *vcpu_to_pi(struct kvm_vcpu *vcpu)
return (struct vcpu_pi *)vcpu;
}
-static inline struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu)
+struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu)
{
return &vcpu_to_pi(vcpu)->pi_desc;
}
diff --git a/arch/x86/kvm/vmx/posted_intr.h b/arch/x86/kvm/vmx/posted_intr.h
index 2fe8222308b2..0f9983b6910b 100644
--- a/arch/x86/kvm/vmx/posted_intr.h
+++ b/arch/x86/kvm/vmx/posted_intr.h
@@ -105,6 +105,8 @@ struct vcpu_pi {
/* Until here common layout betwwn vcpu_vmx and vcpu_tdx. */
};
+struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu);
+
void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu);
void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu);
void pi_wakeup_handler(void);
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index ab5af39dd7b3..d19e53605f12 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -528,6 +528,9 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
vcpu->arch.guest_state_protected =
!(to_kvm_tdx(vcpu->kvm)->attributes & TDX_TD_ATTRIBUTE_DEBUG);
+ tdx->pi_desc.nv = POSTED_INTR_VECTOR;
+ tdx->pi_desc.sn = 1;
+
tdx->host_state_need_save = true;
tdx->host_state_need_restore = false;
@@ -538,6 +541,7 @@ void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct vcpu_tdx *tdx = to_tdx(vcpu);
+ vmx_vcpu_pi_load(vcpu, cpu);
if (vcpu->cpu == cpu)
return;
@@ -715,6 +719,12 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
trace_kvm_entry(vcpu);
+ if (pi_test_on(&tdx->pi_desc)) {
+ apic->send_IPI_self(POSTED_INTR_VECTOR);
+
+ kvm_wait_lapic_expire(vcpu);
+ }
+
tdx_vcpu_enter_exit(vcpu, tdx);
tdx_user_return_update_cache();
@@ -1046,6 +1056,16 @@ static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn,
return tdx_sept_drop_private_spte(kvm, gfn, level, pfn);
}
+void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
+ int trig_mode, int vector)
+{
+ struct kvm_vcpu *vcpu = apic->vcpu;
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ /* TDX supports only posted interrupt. No lapic emulation. */
+ __vmx_deliver_posted_interrupt(vcpu, &tdx->pi_desc, vector);
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
@@ -1775,6 +1795,10 @@ int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp)
if (ret)
return ret;
+ td_vmcs_write16(tdx, POSTED_INTR_NV, POSTED_INTR_VECTOR);
+ td_vmcs_write64(tdx, POSTED_INTR_DESC_ADDR, __pa(&tdx->pi_desc));
+ td_vmcs_setbit32(tdx, PIN_BASED_VM_EXEC_CONTROL, PIN_BASED_POSTED_INTR);
+
tdx->initialized = true;
return 0;
}
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b8d8f7fbeb69..ebf262496f47 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4149,50 +4149,6 @@ void vmx_msr_filter_changed(struct kvm_vcpu *vcpu)
pt_update_intercept_for_msr(vcpu);
}
-static inline void kvm_vcpu_trigger_posted_interrupt(struct kvm_vcpu *vcpu,
- int pi_vec)
-{
-#ifdef CONFIG_SMP
- if (vcpu->mode == IN_GUEST_MODE) {
- /*
- * The vector of the virtual has already been set in the PIR.
- * Send a notification event to deliver the virtual interrupt
- * unless the vCPU is the currently running vCPU, i.e. the
- * event is being sent from a fastpath VM-Exit handler, in
- * which case the PIR will be synced to the vIRR before
- * re-entering the guest.
- *
- * When the target is not the running vCPU, the following
- * possibilities emerge:
- *
- * Case 1: vCPU stays in non-root mode. Sending a notification
- * event posts the interrupt to the vCPU.
- *
- * Case 2: vCPU exits to root mode and is still runnable. The
- * PIR will be synced to the vIRR before re-entering the guest.
- * Sending a notification event is ok as the host IRQ handler
- * will ignore the spurious event.
- *
- * Case 3: vCPU exits to root mode and is blocked. vcpu_block()
- * has already synced PIR to vIRR and never blocks the vCPU if
- * the vIRR is not empty. Therefore, a blocked vCPU here does
- * not wait for any requested interrupts in PIR, and sending a
- * notification event also results in a benign, spurious event.
- */
-
- if (vcpu != kvm_get_running_vcpu())
- apic->send_IPI_mask(get_cpu_mask(vcpu->cpu), pi_vec);
- return;
- }
-#endif
- /*
- * The vCPU isn't in the guest; wake the vCPU in case it is blocking,
- * otherwise do nothing as KVM will grab the highest priority pending
- * IRQ via ->sync_pir_to_irr() in vcpu_enter_guest().
- */
- kvm_vcpu_wake_up(vcpu);
-}
-
static int vmx_deliver_nested_posted_interrupt(struct kvm_vcpu *vcpu,
int vector)
{
@@ -4245,20 +4201,7 @@ static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
if (!vcpu->arch.apic->apicv_active)
return -1;
- if (pi_test_and_set_pir(vector, &vmx->pi_desc))
- return 0;
-
- /* If a previous notification has sent the IPI, nothing to do. */
- if (pi_test_and_set_on(&vmx->pi_desc))
- return 0;
-
- /*
- * The implied barrier in pi_test_and_set_on() pairs with the smp_mb_*()
- * after setting vcpu->mode in vcpu_enter_guest(), thus the vCPU is
- * guaranteed to see PID.ON=1 and sync the PIR to IRR if triggering a
- * posted interrupt "fails" because vcpu->mode != IN_GUEST_MODE.
- */
- kvm_vcpu_trigger_posted_interrupt(vcpu, POSTED_INTR_VECTOR);
+ __vmx_deliver_posted_interrupt(vcpu, &vmx->pi_desc, vector);
return 0;
}
@@ -6902,14 +6845,6 @@ void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
vmcs_write64(EOI_EXIT_BITMAP3, eoi_exit_bitmap[3]);
}
-void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu)
-{
- struct vcpu_vmx *vmx = to_vmx(vcpu);
-
- pi_clear_on(&vmx->pi_desc);
- memset(vmx->pi_desc.pir, 0, sizeof(vmx->pi_desc.pir));
-}
-
void vmx_do_interrupt_irqoff(unsigned long entry);
void vmx_do_nmi_irqoff(void);
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 4c788f34b777..586478ced9f7 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -62,7 +62,6 @@ int vmx_check_intercept(struct kvm_vcpu *vcpu,
bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu);
void vmx_migrate_timers(struct kvm_vcpu *vcpu);
void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu);
-void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu);
bool vmx_check_apicv_inhibit_reasons(enum kvm_apicv_inhibit reason);
void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr);
void vmx_hwapic_isr_update(int max_isr);
@@ -164,6 +163,9 @@ void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu);
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
+void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
+ int trig_mode, int vector);
+
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
void tdx_flush_tlb(struct kvm_vcpu *vcpu);
@@ -197,6 +199,9 @@ static inline void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) {}
static inline bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu) { return false; }
static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
+static inline void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
+ int trig_mode, int vector) {}
+
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
static inline void tdx_flush_tlb(struct kvm_vcpu *vcpu) {}
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX protects TDX guest APIC state from VMM. Implement access methods of
TDX guest vAPIC state to ignore them or return zero.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 61 ++++++++++++++++++++++++++++++++++----
arch/x86/kvm/vmx/tdx.c | 6 ++++
arch/x86/kvm/vmx/x86_ops.h | 3 ++
3 files changed, 64 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 21aebf38697a..c79f46ede97e 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -364,6 +364,14 @@ static bool vt_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
return vmx_apic_init_signal_blocked(vcpu);
}
+static void vt_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_set_virtual_apic_mode(vcpu);
+
+ return vmx_set_virtual_apic_mode(vcpu);
+}
+
static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
struct pi_desc *pi = vcpu_to_pi_desc(vcpu);
@@ -372,6 +380,31 @@ static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
memset(pi->pir, 0, sizeof(pi->pir));
}
+static void vt_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ return vmx_hwapic_irr_update(vcpu, max_irr);
+}
+
+static void vt_hwapic_isr_update(int max_isr)
+{
+ if (is_td_vcpu(kvm_get_running_vcpu()))
+ return;
+
+ return vmx_hwapic_isr_update(max_isr);
+}
+
+static bool vt_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
+{
+ /* TDX doesn't support L2 at the moment. */
+ if (WARN_ON_ONCE(is_td_vcpu(vcpu)))
+ return false;
+
+ return vmx_guest_apic_has_interrupt(vcpu);
+}
+
static int vt_sync_pir_to_irr(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu))
@@ -809,6 +842,22 @@ static void vt_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
vmx_update_cr8_intercept(vcpu, tpr, irr);
}
+static void vt_set_apic_access_page_addr(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_set_apic_access_page_addr(vcpu);
+}
+
+static void vt_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
+{
+ if (WARN_ON_ONCE(is_td_vcpu(vcpu)))
+ return;
+
+ vmx_refresh_apicv_exec_ctrl(vcpu);
+}
+
static void vt_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
{
if (is_td_vcpu(vcpu))
@@ -1019,15 +1068,15 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.enable_nmi_window = vt_enable_nmi_window,
.enable_irq_window = vt_enable_irq_window,
.update_cr8_intercept = vt_update_cr8_intercept,
- .set_virtual_apic_mode = vmx_set_virtual_apic_mode,
- .set_apic_access_page_addr = vmx_set_apic_access_page_addr,
- .refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
+ .set_virtual_apic_mode = vt_set_virtual_apic_mode,
+ .set_apic_access_page_addr = vt_set_apic_access_page_addr,
+ .refresh_apicv_exec_ctrl = vt_refresh_apicv_exec_ctrl,
.load_eoi_exitmap = vt_load_eoi_exitmap,
.apicv_post_state_restore = vt_apicv_post_state_restore,
.required_apicv_inhibits = VMX_REQUIRED_APICV_INHIBITS,
- .hwapic_irr_update = vmx_hwapic_irr_update,
- .hwapic_isr_update = vmx_hwapic_isr_update,
- .guest_apic_has_interrupt = vmx_guest_apic_has_interrupt,
+ .hwapic_irr_update = vt_hwapic_irr_update,
+ .hwapic_isr_update = vt_hwapic_isr_update,
+ .guest_apic_has_interrupt = vt_guest_apic_has_interrupt,
.sync_pir_to_irr = vt_sync_pir_to_irr,
.deliver_interrupt = vt_deliver_interrupt,
.dy_apicv_has_pending_interrupt = pi_has_pending_interrupt,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 23a184d5ab47..8e392bc3330b 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1866,6 +1866,12 @@ void tdx_enable_smi_window(struct kvm_vcpu *vcpu)
}
#endif
+void tdx_set_virtual_apic_mode(struct kvm_vcpu *vcpu)
+{
+ /* Only x2APIC mode is supported for TD. */
+ WARN_ON_ONCE(kvm_get_apic_mode(vcpu) != LAPIC_MODE_X2APIC);
+}
+
int tdx_get_cpl(struct kvm_vcpu *vcpu)
{
return 0;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 9be0ac32d2b4..d049e0c72ed0 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -174,6 +174,7 @@ void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
bool tdx_has_emulated_msr(u32 index, bool write);
int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
+void tdx_set_virtual_apic_mode(struct kvm_vcpu *vcpu);
int tdx_get_cpl(struct kvm_vcpu *vcpu);
void tdx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg);
@@ -226,6 +227,8 @@ static inline bool tdx_has_emulated_msr(u32 index, bool write) { return false; }
static inline int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) { return 1; }
static inline int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) { return 1; }
+static inline void tdx_set_virtual_apic_mode(struct kvm_vcpu *vcpu) {}
+
static inline int tdx_get_cpl(struct kvm_vcpu *vcpu) { return 0; }
static inline void tdx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg) {}
static inline unsigned long tdx_get_rflags(struct kvm_vcpu *vcpu) { return 0; }
--
2.25.1
From: Isaku Yamahata <[email protected]>
Currently TDX KVM doesn't support tracking dirty pages (yet). Implement a
method to ignore it. Because the flag for kvm memory slot to enable dirty
logging isn't accepted for TDX, warn on the method is called for TDX.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 59fa63146c8d..c9bbee1b69e9 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -828,6 +828,14 @@ static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
return __vmx_get_mt_mask(vcpu, gfn, is_mmio, true);
}
+static void vt_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
+{
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return;
+
+ vmx_update_cpu_dirty_logging(vcpu);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -972,7 +980,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.sched_in = vt_sched_in,
.cpu_dirty_log_size = PML_ENTITY_NUM,
- .update_cpu_dirty_logging = vmx_update_cpu_dirty_logging,
+ .update_cpu_dirty_logging = vt_update_cpu_dirty_logging,
.nested_ops = &vmx_nested_ops,
--
2.25.1
From: Isaku Yamahata <[email protected]>
The TDX module API doesn't provide API for VMM to inject INIT IPI and SIPI.
Instead it defines the different protocols to boot application processors.
Ignore INIT and SIPI events for the TDX guest.
There are two options. 1) (silently) ignore INIT/SIPI request or 2) return
error to guest TDs somehow. Given that TDX guest is paravirtualized to
boot AP, the option 1 is chosen for simplicity.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/lapic.c | 19 +++++++++++-------
arch/x86/kvm/svm/svm.c | 1 +
arch/x86/kvm/vmx/main.c | 32 ++++++++++++++++++++++++++++--
arch/x86/kvm/vmx/tdx.c | 4 ++--
6 files changed, 48 insertions(+), 11 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e1242c4b248f..5f699a93b9b3 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -144,6 +144,7 @@ KVM_X86_OP_OPTIONAL(migrate_timers)
KVM_X86_OP(msr_filter_changed)
KVM_X86_OP(complete_emulated_msr)
KVM_X86_OP(vcpu_deliver_sipi_vector)
+KVM_X86_OP(vcpu_deliver_init)
KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons);
#undef KVM_X86_OP
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 50e3666ec6f6..ae377eec8198 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1803,6 +1803,7 @@ struct kvm_x86_ops {
int (*complete_emulated_msr)(struct kvm_vcpu *vcpu, int err);
void (*vcpu_deliver_sipi_vector)(struct kvm_vcpu *vcpu, u8 vector);
+ void (*vcpu_deliver_init)(struct kvm_vcpu *vcpu);
/*
* Returns vCPU specific APICv inhibit reasons
@@ -2014,6 +2015,7 @@ void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
void kvm_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, int seg);
void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector);
+void kvm_vcpu_deliver_init(struct kvm_vcpu *vcpu);
int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index,
int reason, bool has_error_code, u32 error_code);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 6b2e2d38a48b..ada59db5b963 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -3220,6 +3220,16 @@ int kvm_lapic_set_pv_eoi(struct kvm_vcpu *vcpu, u64 data, unsigned long len)
return 0;
}
+void kvm_vcpu_deliver_init(struct kvm_vcpu *vcpu)
+{
+ kvm_vcpu_reset(vcpu, true);
+ if (kvm_vcpu_is_bsp(vcpu))
+ vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
+ else
+ vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
+}
+EXPORT_SYMBOL_GPL(kvm_vcpu_deliver_init);
+
int kvm_apic_accept_events(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
@@ -3251,13 +3261,8 @@ int kvm_apic_accept_events(struct kvm_vcpu *vcpu)
return 0;
}
- if (test_and_clear_bit(KVM_APIC_INIT, &apic->pending_events)) {
- kvm_vcpu_reset(vcpu, true);
- if (kvm_vcpu_is_bsp(apic->vcpu))
- vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
- else
- vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
- }
+ if (test_and_clear_bit(KVM_APIC_INIT, &apic->pending_events))
+ static_call(kvm_x86_vcpu_deliver_init)(vcpu);
if (test_and_clear_bit(KVM_APIC_SIPI, &apic->pending_events)) {
if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
/* evaluate pending_events before reading the vector */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 687df130fbad..8d3b3cc24c9d 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4830,6 +4830,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
.complete_emulated_msr = svm_complete_emulated_msr,
.vcpu_deliver_sipi_vector = svm_vcpu_deliver_sipi_vector,
+ .vcpu_deliver_init = kvm_vcpu_deliver_init,
.vcpu_get_apicv_inhibit_reasons = avic_vcpu_get_apicv_inhibit_reasons,
};
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index a01efaa10bbc..73d330488bfe 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -332,6 +332,14 @@ static void vt_enable_smi_window(struct kvm_vcpu *vcpu)
}
#endif
+static bool vt_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return true;
+
+ return vmx_apic_init_signal_blocked(vcpu);
+}
+
static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
struct pi_desc *pi = vcpu_to_pi_desc(vcpu);
@@ -360,6 +368,25 @@ static void vt_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
vmx_deliver_interrupt(apic, delivery_mode, trig_mode, vector);
}
+static void vt_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ kvm_vcpu_deliver_sipi_vector(vcpu, vector);
+}
+
+static void vt_vcpu_deliver_init(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ /* TDX doesn't support INIT. Ignore INIT event */
+ vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
+ return;
+ }
+
+ kvm_vcpu_deliver_init(vcpu);
+}
+
static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
{
if (is_td_vcpu(vcpu)) {
@@ -724,13 +751,14 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
#endif
.can_emulate_instruction = vmx_can_emulate_instruction,
- .apic_init_signal_blocked = vmx_apic_init_signal_blocked,
+ .apic_init_signal_blocked = vt_apic_init_signal_blocked,
.migrate_timers = vmx_migrate_timers,
.msr_filter_changed = vt_msr_filter_changed,
.complete_emulated_msr = kvm_complete_insn_gp,
- .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
+ .vcpu_deliver_sipi_vector = vt_vcpu_deliver_sipi_vector,
+ .vcpu_deliver_init = vt_vcpu_deliver_init,
.dev_mem_enc_ioctl = tdx_dev_ioctl,
.mem_enc_ioctl = vt_mem_enc_ioctl,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 5c6f8b73b820..098e87e7e507 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -730,8 +730,8 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu)
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
- /* Ignore INIT silently because TDX doesn't support INIT event. */
- if (init_event)
+ /* vcpu_deliver_init method silently discards INIT event. */
+ if (KVM_BUG_ON(init_event, vcpu->kvm))
return;
if (KVM_BUG_ON(is_td_vcpu_created(to_tdx(vcpu)), vcpu->kvm))
return;
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up TDX PV port IO hypercall to the KVM backend function.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 57 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index a28399d1fd6e..12cc670eddf7 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1014,6 +1014,61 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
return kvm_emulate_halt_noskip(vcpu);
}
+static int tdx_complete_pio_in(struct kvm_vcpu *vcpu)
+{
+ struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
+ unsigned long val = 0;
+ int ret;
+
+ WARN_ON_ONCE(vcpu->arch.pio.count != 1);
+
+ ret = ctxt->ops->pio_in_emulated(ctxt, vcpu->arch.pio.size,
+ vcpu->arch.pio.port, &val, 1);
+ WARN_ON_ONCE(!ret);
+
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ tdvmcall_set_return_val(vcpu, val);
+
+ return 1;
+}
+
+static int tdx_emulate_io(struct kvm_vcpu *vcpu)
+{
+ struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
+ unsigned long val = 0;
+ unsigned int port;
+ int size, ret;
+ bool write;
+
+ ++vcpu->stat.io_exits;
+
+ size = tdvmcall_a0_read(vcpu);
+ write = tdvmcall_a1_read(vcpu);
+ port = tdvmcall_a2_read(vcpu);
+
+ if (size != 1 && size != 2 && size != 4) {
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+ }
+
+ if (write) {
+ val = tdvmcall_a3_read(vcpu);
+ ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val, 1);
+
+ /* No need for a complete_userspace_io callback. */
+ vcpu->arch.pio.count = 0;
+ } else {
+ ret = ctxt->ops->pio_in_emulated(ctxt, size, port, &val, 1);
+ if (!ret)
+ vcpu->arch.complete_userspace_io = tdx_complete_pio_in;
+ else
+ tdvmcall_set_return_val(vcpu, val);
+ }
+ if (ret)
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ return ret;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -1024,6 +1079,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
return tdx_emulate_cpuid(vcpu);
case EXIT_REASON_HLT:
return tdx_emulate_hlt(vcpu);
+ case EXIT_REASON_IO_INSTRUCTION:
+ return tdx_emulate_io(vcpu);
default:
break;
}
--
2.25.1
From: Isaku Yamahata <[email protected]>
Add documentation to Intel Trusted Domain Extensions(TDX) support.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/virt/kvm/api.rst | 9 +-
Documentation/virt/kvm/index.rst | 1 +
Documentation/virt/kvm/intel-tdx.rst | 357 +++++++++++++++++++++++++++
3 files changed, 366 insertions(+), 1 deletion(-)
create mode 100644 Documentation/virt/kvm/intel-tdx.rst
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 7a34efd31dcc..d6eb3f80575c 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -1375,6 +1375,9 @@ the memory region are automatically reflected into the guest. For example, an
mmap() that affects the region will be made visible immediately. Another
example is madvise(MADV_DROP).
+For TDX guest, deleting/moving memory region loses guest memory contents.
+Read only region isn't supported. Only as-id 0 is supported.
+
Note: On arm64, a write generated by the page-table walker (to update
the Access and Dirty flags, for example) never results in a
KVM_EXIT_MMIO exit when the slot has the KVM_MEM_READONLY flag. This
@@ -4692,7 +4695,7 @@ H_GET_CPU_CHARACTERISTICS hypercall.
:Capability: basic
:Architectures: x86
-:Type: vm
+:Type: vm ioctl, vcpu ioctl
:Parameters: an opaque platform specific structure (in/out)
:Returns: 0 on success; -1 on error
@@ -4704,6 +4707,10 @@ Currently, this ioctl is used for issuing Secure Encrypted Virtualization
(SEV) commands on AMD Processors. The SEV commands are defined in
Documentation/virt/kvm/x86/amd-memory-encryption.rst.
+Currently, this ioctl is used for issuing Trusted Domain Extensions
+(TDX) commands on Intel Processors. The TDX commands are defined in
+Documentation/virt/kvm/intel-tdx.rst.
+
4.111 KVM_MEMORY_ENCRYPT_REG_REGION
-----------------------------------
diff --git a/Documentation/virt/kvm/index.rst b/Documentation/virt/kvm/index.rst
index 7f5f803fa87a..41d1e59a65be 100644
--- a/Documentation/virt/kvm/index.rst
+++ b/Documentation/virt/kvm/index.rst
@@ -20,4 +20,5 @@ KVM
halt-polling
review-checklist
+ intel-tdx
intel-tdx-layer-status.rst
diff --git a/Documentation/virt/kvm/intel-tdx.rst b/Documentation/virt/kvm/intel-tdx.rst
new file mode 100644
index 000000000000..9a299923844d
--- /dev/null
+++ b/Documentation/virt/kvm/intel-tdx.rst
@@ -0,0 +1,357 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================================
+Intel Trust Domain Extensions (TDX)
+===================================
+
+Overview
+========
+TDX stands for Trust Domain Extensions which isolates VMs from
+the virtual-machine manager (VMM)/hypervisor and any other software on
+the platform. For details, see the specifications [1]_, whitepaper [2]_,
+architectural extensions specification [3]_, module documentation [4]_,
+loader interface specification [5]_, guest-hypervisor communication
+interface [6]_, virtual firmware design guide [7]_, and other resources
+([8]_, [9]_, [10]_, [11]_, and [12]_).
+
+
+API description
+===============
+
+KVM_MEMORY_ENCRYPT_OP
+---------------------
+:Type: vm ioctl, vcpu ioctl
+
+For TDX operations, KVM_MEMORY_ENCRYPT_OP is re-purposed to be generic
+ioctl with TDX specific sub ioctl command.
+
+::
+
+ /* Trust Domain eXtension sub-ioctl() commands. */
+ enum kvm_tdx_cmd_id {
+ KVM_TDX_CAPABILITIES = 0,
+ KVM_TDX_INIT_VM,
+ KVM_TDX_INIT_VCPU,
+ KVM_TDX_INIT_MEM_REGION,
+ KVM_TDX_FINALIZE_VM,
+
+ KVM_TDX_CMD_NR_MAX,
+ };
+
+ struct kvm_tdx_cmd {
+ /* enum kvm_tdx_cmd_id */
+ __u32 id;
+ /* flags for sub-commend. If sub-command doesn't use this, set zero. */
+ __u32 flags;
+ /*
+ * data for each sub-command. An immediate or a pointer to the actual
+ * data in process virtual address. If sub-command doesn't use it,
+ * set zero.
+ */
+ __u64 data;
+ /*
+ * Auxiliary error code. The sub-command may return TDX SEAMCALL
+ * status code in addition to -Exxx.
+ * Defined for consistency with struct kvm_sev_cmd.
+ */
+ __u64 error;
+ /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
+ __u64 unused;
+ };
+
+KVM_TDX_CAPABILITIES
+--------------------
+:Type: vm ioctl
+
+Subset of TDSYSINFO_STRCUCT retrieved by TDH.SYS.INFO TDX SEAM call will be
+returned. Which describes about Intel TDX module.
+
+- id: KVM_TDX_CAPABILITIES
+- flags: must be 0
+- data: pointer to struct kvm_tdx_capabilities
+- error: must be 0
+- unused: must be 0
+
+::
+
+ struct kvm_tdx_cpuid_config {
+ __u32 leaf;
+ __u32 sub_leaf;
+ __u32 eax;
+ __u32 ebx;
+ __u32 ecx;
+ __u32 edx;
+ };
+
+ struct kvm_tdx_capabilities {
+ __u64 attrs_fixed0;
+ __u64 attrs_fixed1;
+ __u64 xfam_fixed0;
+ __u64 xfam_fixed1;
+
+ __u32 nr_cpuid_configs;
+ struct kvm_tdx_cpuid_config cpuid_configs[0];
+ };
+
+
+KVM_TDX_INIT_VM
+---------------
+:Type: vm ioctl
+
+Does additional VM initialization specific to TDX which corresponds to
+TDH.MNG.INIT TDX SEAM call.
+
+- id: KVM_TDX_INIT_VM
+- flags: must be 0
+- data: pointer to struct kvm_tdx_init_vm
+- error: must be 0
+- unused: must be 0
+
+::
+
+ struct kvm_tdx_init_vm {
+ __u64 attributes;
+ __u64 mrconfigid[6]; /* sha384 digest */
+ __u64 mrowner[6]; /* sha384 digest */
+ __u64 mrownerconfig[6]; /* sha348 digest */
+ __u64 reserved[1004]; /* must be zero for future extensibility */
+
+ struct kvm_cpuid2 cpuid;
+ };
+
+
+KVM_TDX_INIT_VCPU
+-----------------
+:Type: vcpu ioctl
+
+Does additional VCPU initialization specific to TDX which corresponds to
+TDH.VP.INIT TDX SEAM call.
+
+- id: KVM_TDX_INIT_VCPU
+- flags: must be 0
+- data: initial value of the guest TD VCPU RCX
+- error: must be 0
+- unused: must be 0
+
+KVM_TDX_INIT_MEM_REGION
+-----------------------
+:Type: vm ioctl
+
+Encrypt a memory continuous region which corresponding to TDH.MEM.PAGE.ADD
+TDX SEAM call.
+If KVM_TDX_MEASURE_MEMORY_REGION flag is specified, it also extends measurement
+which corresponds to TDH.MR.EXTEND TDX SEAM call.
+
+- id: KVM_TDX_INIT_VCPU
+- flags: flags
+ currently only KVM_TDX_MEASURE_MEMORY_REGION is defined
+- data: pointer to struct kvm_tdx_init_mem_region
+- error: must be 0
+- unused: must be 0
+
+::
+
+ #define KVM_TDX_MEASURE_MEMORY_REGION (1UL << 0)
+
+ struct kvm_tdx_init_mem_region {
+ __u64 source_addr;
+ __u64 gpa;
+ __u64 nr_pages;
+ };
+
+
+KVM_TDX_FINALIZE_VM
+-------------------
+:Type: vm ioctl
+
+Complete measurement of the initial TD contents and mark it ready to run
+which corresponds to TDH.MR.FINALIZE
+
+- id: KVM_TDX_FINALIZE_VM
+- flags: must be 0
+- data: must be 0
+- error: must be 0
+- unused: must be 0
+
+KVM TDX creation flow
+=====================
+In addition to KVM normal flow, new TDX ioctls need to be called. The control flow
+looks like as follows.
+
+#. system wide capability check
+
+ * KVM_CAP_VM_TYPES: check if VM type is supported and if KVM_X86_PROTECTED_VM
+ is supported.
+
+#. creating VM
+
+ * KVM_CREATE_VM
+ * KVM_TDX_CAPABILITIES: query if TDX is supported on the platform.
+ * KVM_ENABLE_CAP_VM(KVM_CAP_MAX_VCPUS): set max_vcpus. KVM_MAX_VCPUS by
+ default. KVM_MAX_VCPUS is not a part of ABI, but kernel internal constant
+ that is subject to change. Because max vcpus is a part of attestation, max
+ vcpus should be explicitly set.
+ * KVM_SET_TSC_KHZ for vm. optional
+ * KVM_TDX_INIT_VM: pass TDX specific VM parameters.
+
+#. creating VCPU
+
+ * KVM_CREATE_VCPU
+ * KVM_TDX_INIT_VCPU: pass TDX specific VCPU parameters.
+ * KVM_SET_CPUID2: Enable CPUID[0x1].ECX.X2APIC(bit 21)=1 so that the following
+ setting of MSR_IA32_APIC_BASE success. Without this,
+ KVM_SET_MSRS(MSR_IA32_APIC_BASE) fails.
+ * KVM_SET_MSRS: Set the initial reset value of MSR_IA32_APIC_BASE to
+ APIC_DEFAULT_ADDRESS(0xfee00000) | XAPIC_ENABLE(bit 10) |
+ X2APIC_ENABLE(bit 11) [| MSR_IA32_APICBASE_BSP(bit 8) optional]
+
+#. initializing guest memory
+
+ * allocate guest memory and initialize page same to normal KVM case
+ In TDX case, parse and load TDVF into guest memory in addition.
+ * KVM_TDX_INIT_MEM_REGION to add and measure guest pages.
+ If the pages has contents above, those pages need to be added.
+ Otherwise the contents will be lost and guest sees zero pages.
+ * KVM_TDX_FINALIAZE_VM: Finalize VM and measurement
+ This must be after KVM_TDX_INIT_MEM_REGION.
+
+#. run vcpu
+
+Design discussion
+=================
+
+Coexistence of normal(VMX) VM and TD VM
+---------------------------------------
+It's required to allow both legacy(normal VMX) VMs and new TD VMs to
+coexist. Otherwise the benefits of VM flexibility would be eliminated.
+The main issue for it is that the logic of kvm_x86_ops callbacks for
+TDX is different from VMX. On the other hand, the variable,
+kvm_x86_ops, is global single variable. Not per-VM, not per-vcpu.
+
+Several points to be considered:
+
+ * No or minimal overhead when TDX is disabled(CONFIG_INTEL_TDX_HOST=n).
+ * Avoid overhead of indirect call via function pointers.
+ * Contain the changes under arch/x86/kvm/vmx directory and share logic
+ with VMX for maintenance.
+ Even though the ways to operation on VM (VMX instruction vs TDX
+ SEAM call) are different, the basic idea remains the same. So, many
+ logic can be shared.
+ * Future maintenance
+ The huge change of kvm_x86_ops in (near) future isn't expected.
+ a centralized file is acceptable.
+
+- Wrapping kvm x86_ops: The current choice
+
+ Introduce dedicated file for arch/x86/kvm/vmx/main.c (the name,
+ main.c, is just chosen to show main entry points for callbacks.) and
+ wrapper functions around all the callbacks with
+ "if (is-tdx) tdx-callback() else vmx-callback()".
+
+ Pros:
+
+ - No major change in common x86 KVM code. The change is (mostly)
+ contained under arch/x86/kvm/vmx/.
+ - When TDX is disabled(CONFIG_INTEL_TDX_HOST=n), the overhead is
+ optimized out.
+ - Micro optimization by avoiding function pointer.
+
+ Cons:
+
+ - Many boiler plates in arch/x86/kvm/vmx/main.c.
+
+KVM MMU Changes
+---------------
+KVM MMU needs to be enhanced to handle Secure/Shared-EPT. The
+high-level execution flow is mostly same to normal EPT case.
+EPT violation/misconfiguration -> invoke TDP fault handler ->
+resolve TDP fault -> resume execution. (or emulate MMIO)
+The difference is, that S-EPT is operated(read/write) via TDX SEAM
+call which is expensive instead of direct read/write EPT entry.
+One bit of GPA (51 or 47 bit) is repurposed so that it means shared
+with host(if set to 1) or private to TD(if cleared to 0).
+
+- The current implementation
+
+ * Reuse the existing MMU code with minimal update. Because the
+ execution flow is mostly same. But additional operation, TDX call
+ for S-EPT, is needed. So add hooks for it to kvm_x86_ops.
+ * For performance, minimize TDX SEAM call to operate on S-EPT. When
+ getting corresponding S-EPT pages/entry from faulting GPA, don't
+ use TDX SEAM call to read S-EPT entry. Instead create shadow copy
+ in host memory.
+ Repurpose the existing kvm_mmu_page as shadow copy of S-EPT and
+ associate S-EPT to it.
+ * Treats share bit as attributes. mask/unmask the bit where
+ necessary to keep the existing traversing code works.
+ Introduce kvm.arch.gfn_shared_mask and use "if (gfn_share_mask)"
+ for special case.
+
+ * 0 : for non-TDX case
+ * 51 or 47 bit set for TDX case.
+
+ Pros:
+
+ - Large code reuse with minimal new hooks.
+ - Execution path is same.
+
+ Cons:
+
+ - Complicates the existing code.
+ - Repurpose kvm_mmu_page as shadow of Secure-EPT can be confusing.
+
+New KVM API, ioctl (sub)command, to manage TD VMs
+-------------------------------------------------
+Additional KVM APIs are needed to control TD VMs. The operations on TD
+VMs are specific to TDX.
+
+- Piggyback and repurpose KVM_MEMORY_ENCRYPT_OP
+
+ Although operations for TD VMs aren't necessarily related to memory
+ encryption, define sub operations of KVM_MEMORY_ENCRYPT_OP for TDX specific
+ ioctls.
+
+ Pros:
+
+ - No major change in common x86 KVM code.
+ - Follows the SEV case.
+
+ Cons:
+
+ - The sub operations of KVM_MEMORY_ENCRYPT_OP aren't necessarily memory
+ encryption, but operations on TD VMs.
+
+References
+==========
+
+.. [1] TDX specification
+ https://software.intel.com/content/www/us/en/develop/articles/intel-trust-domain-extensions.html
+.. [2] Intel Trust Domain Extensions (Intel TDX)
+ https://software.intel.com/content/dam/develop/external/us/en/documents/tdx-whitepaper-final9-17.pdf
+.. [3] Intel CPU Architectural Extensions Specification
+ https://software.intel.com/content/dam/develop/external/us/en/documents/intel-tdx-cpu-architectural-specification.pdf
+.. [4] Intel TDX Module 1.0 EAS
+ https://software.intel.com/content/dam/develop/external/us/en/documents/intel-tdx-module-1eas.pdf
+.. [5] Intel TDX Loader Interface Specification
+ https://software.intel.com/content/dam/develop/external/us/en/documents/intel-tdx-seamldr-interface-specification.pdf
+.. [6] Intel TDX Guest-Hypervisor Communication Interface
+ https://software.intel.com/content/dam/develop/external/us/en/documents/intel-tdx-guest-hypervisor-communication-interface.pdf
+.. [7] Intel TDX Virtual Firmware Design Guide
+ https://software.intel.com/content/dam/develop/external/us/en/documents/tdx-virtual-firmware-design-guide-rev-1.
+.. [8] intel public github
+
+ * kvm TDX branch: https://github.com/intel/tdx/tree/kvm
+ * TDX guest branch: https://github.com/intel/tdx/tree/guest
+
+.. [9] tdvf
+ https://github.com/tianocore/edk2-staging/tree/TDVF
+.. [10] KVM forum 2020: Intel Virtualization Technology Extensions to
+ Enable Hardware Isolated VMs
+ https://osseu2020.sched.com/event/eDzm/intel-virtualization-technology-extensions-to-enable-hardware-isolated-vms-sean-christopherson-intel
+.. [11] Linux Security Summit EU 2020:
+ Architectural Extensions for Hardware Virtual Machine Isolation
+ to Advance Confidential Computing in Public Clouds - Ravi Sahita
+ & Jun Nakajima, Intel Corporation
+ https://osseu2020.sched.com/event/eDOx/architectural-extensions-for-hardware-virtual-machine-isolation-to-advance-confidential-computing-in-public-clouds-ravi-sahita-jun-nakajima-intel-corporation
+.. [12] [RFCv2,00/16] KVM protected memory extension
+ https://lkml.org/lkml/2020/10/20/66
--
2.25.1
From: Isaku Yamahata <[email protected]>
TDX doesn't support VMX preemption timer. Implement access methods for VMM
to ignore VMX preemption timer.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/main.c | 25 +++++++++++++++++++++++--
1 file changed, 23 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index c9bbee1b69e9..32c992b5ab0d 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -836,6 +836,27 @@ static void vt_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
vmx_update_cpu_dirty_logging(vcpu);
}
+#ifdef CONFIG_X86_64
+static int vt_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
+ bool *expired)
+{
+ /* VMX-preemption timer isn't available for TDX. */
+ if (is_td_vcpu(vcpu))
+ return -EINVAL;
+
+ return vmx_set_hv_timer(vcpu, guest_deadline_tsc, expired);
+}
+
+static void vt_cancel_hv_timer(struct kvm_vcpu *vcpu)
+{
+ /* VMX-preemption timer can't be set. See vt_set_hv_timer(). */
+ if (KVM_BUG_ON(is_td_vcpu(vcpu), vcpu->kvm))
+ return;
+
+ vmx_cancel_hv_timer(vcpu);
+}
+#endif
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -988,8 +1009,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.pi_start_assignment = vmx_pi_start_assignment,
#ifdef CONFIG_X86_64
- .set_hv_timer = vmx_set_hv_timer,
- .cancel_hv_timer = vmx_cancel_hv_timer,
+ .set_hv_timer = vt_set_hv_timer,
+ .cancel_hv_timer = vt_cancel_hv_timer,
#endif
.setup_mce = vmx_setup_mce,
--
2.25.1
From: Isaku Yamahata <[email protected]>
Now we are able to inject interrupts into TDX vcpu, it's ready to block TDX
vcpu. Wire up kvm x86 methods for blocking/unblocking vcpu for TDX. To
unblock on pending events, request immediate exit methods is also needed.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
arch/x86/kvm/vmx/main.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index b3c2be3e78ef..a54b97203e5c 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -382,6 +382,16 @@ static void vt_enable_irq_window(struct kvm_vcpu *vcpu)
vmx_enable_irq_window(vcpu);
}
+static void vt_request_immediate_exit(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu)) {
+ __kvm_request_immediate_exit(vcpu);
+ return;
+ }
+
+ vmx_request_immediate_exit(vcpu);
+}
+
static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
if (is_td_vcpu(vcpu))
@@ -529,7 +539,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.check_intercept = vmx_check_intercept,
.handle_exit_irqoff = vmx_handle_exit_irqoff,
- .request_immediate_exit = vmx_request_immediate_exit,
+ .request_immediate_exit = vt_request_immediate_exit,
.sched_in = vt_sched_in,
--
2.25.1
From: Isaku Yamahata <[email protected]>
Wire up TDX PV HLT hypercall to the KVM backend function.
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/vmx/tdx.c | 42 +++++++++++++++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 3 +++
2 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 62cd3e899560..a28399d1fd6e 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -627,7 +627,32 @@ void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
- return pi_has_pending_interrupt(vcpu);
+ bool ret = pi_has_pending_interrupt(vcpu);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ if (ret || vcpu->arch.mp_state != KVM_MP_STATE_HALTED)
+ return true;
+
+ if (tdx->interrupt_disabled_hlt)
+ return false;
+
+ /*
+ * This is for the case where the virtual interrupt is recognized,
+ * i.e. set in vmcs.RVI, between the STI and "HLT". KVM doesn't have
+ * access to RVI and the interrupt is no longer in the PID (because it
+ * was "recognized". It doesn't get delivered in the guest because the
+ * TDCALL completes before interrupts are enabled.
+ *
+ * TDX modules sets RVI while in an STI interrupt shadow.
+ * - TDExit(typically TDG.VP.VMCALL<HLT>) from the guest to TDX module.
+ * The interrupt shadow at this point is gone.
+ * - It knows that there is an interrupt that can be delivered
+ * (RVI > PPR && EFLAGS.IF=1, the other conditions of 29.2.2 don't
+ * matter)
+ * - It forwards the TDExit nevertheless, to a clueless hypervisor that
+ * has no way to glean either RVI or PPR.
+ */
+ return !!xchg(&tdx->buggy_hlt_workaround, 0);
}
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
@@ -978,6 +1003,17 @@ static int tdx_emulate_cpuid(struct kvm_vcpu *vcpu)
return 1;
}
+static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ /* See tdx_protected_apic_has_interrupt() to avoid heavy seamcall */
+ tdx->interrupt_disabled_hlt = tdvmcall_a0_read(vcpu);
+
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ return kvm_emulate_halt_noskip(vcpu);
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -986,6 +1022,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
switch (tdvmcall_leaf(vcpu)) {
case EXIT_REASON_CPUID:
return tdx_emulate_cpuid(vcpu);
+ case EXIT_REASON_HLT:
+ return tdx_emulate_hlt(vcpu);
default:
break;
}
@@ -1319,6 +1357,8 @@ void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
struct kvm_vcpu *vcpu = apic->vcpu;
struct vcpu_tdx *tdx = to_tdx(vcpu);
+ /* See comment in tdx_protected_apic_has_interrupt(). */
+ tdx->buggy_hlt_workaround = 1;
/* TDX supports only posted interrupt. No lapic emulation. */
__vmx_deliver_posted_interrupt(vcpu, &tdx->pi_desc, vector);
}
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index fa44a1a9295f..71818c500186 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -93,6 +93,9 @@ struct vcpu_tdx {
bool host_state_need_restore;
u64 msr_host_kernel_gs_base;
+ bool interrupt_disabled_hlt;
+ unsigned int buggy_hlt_workaround;
+
/*
* Dummy to make pmu_intel not corrupt memory.
* TODO: Support PMU for TDX. Future work.
--
2.25.1
From: Isaku Yamahata <[email protected]>
Implements set_msr/get_msr/has_emulated_msr methods for TDX to handle
hypercall from guest TD for paravirtualized rdmsr and wrmsr. The TDX
module virtualizes MSRs. For some MSRs, it injects #VE to the guest TD
upon RDMSR or WRMSR. The exact list of such MSRs are defined in the spec.
Upon #VE, the guest TD may execute hypercalls,
TDG.VP.VMCALL<INSTRUCTION.RDMSR> and TDG.VP.VMCALL<INSTRUCTION.WRMSR>,
which are defined in GHCI (Guest-Host Communication Interface) so that the
host VMM (e.g. KVM) can virtualize the MSRs.
There are three classes of MSRs virtualization.
- non-configurable: TDX module directly virtualizes it. VMM can't configure.
the value set by KVM_SET_MSR_INDEX_LIST is ignored.
- configurable: TDX module directly virtualizes it. VMM can configure at the
VM creation time. The value set by KVM_SET_MSR_INDEX_LIST is used.
- #VE case
Guest TD would issue TDG.VP.VMCALL<INSTRUCTION.{WRMSR,RDMSR> and
VMM handles the MSR hypercall. The value set by KVM_SET_MSR_INDEX_LIST is
used.
Signed-off-by: Isaku Yamahata <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
---
Changes v10 -> v11
- added .msr_filter_changed()
---
arch/x86/kvm/vmx/main.c | 44 ++++++++++++++++++++---
arch/x86/kvm/vmx/tdx.c | 74 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 6 ++++
arch/x86/kvm/x86.c | 1 -
arch/x86/kvm/x86.h | 2 ++
5 files changed, 122 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index caeddb212e50..9901d4400b7b 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -259,6 +259,42 @@ static void vt_handle_exit_irqoff(struct kvm_vcpu *vcpu)
vmx_handle_exit_irqoff(vcpu);
}
+static int vt_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+ if (unlikely(is_td_vcpu(vcpu)))
+ return tdx_set_msr(vcpu, msr_info);
+
+ return vmx_set_msr(vcpu, msr_info);
+}
+
+/*
+ * The kvm parameter can be NULL (module initialization, or invocation before
+ * VM creation). Be sure to check the kvm parameter before using it.
+ */
+static bool vt_has_emulated_msr(struct kvm *kvm, u32 index)
+{
+ if (kvm && is_td(kvm))
+ return tdx_has_emulated_msr(index, true);
+
+ return vmx_has_emulated_msr(kvm, index);
+}
+
+static int vt_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+ if (unlikely(is_td_vcpu(vcpu)))
+ return tdx_get_msr(vcpu, msr_info);
+
+ return vmx_get_msr(vcpu, msr_info);
+}
+
+static void vt_msr_filter_changed(struct kvm_vcpu *vcpu)
+{
+ if (is_td_vcpu(vcpu))
+ return;
+
+ vmx_msr_filter_changed(vcpu);
+}
+
static void vt_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
struct pi_desc *pi = vcpu_to_pi_desc(vcpu);
@@ -522,7 +558,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.hardware_enable = vt_hardware_enable,
.hardware_disable = vt_hardware_disable,
- .has_emulated_msr = vmx_has_emulated_msr,
+ .has_emulated_msr = vt_has_emulated_msr,
.is_vm_type_supported = vt_is_vm_type_supported,
.max_vcpus = vt_max_vcpus,
@@ -544,8 +580,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.update_exception_bitmap = vmx_update_exception_bitmap,
.get_msr_feature = vmx_get_msr_feature,
- .get_msr = vmx_get_msr,
- .set_msr = vmx_set_msr,
+ .get_msr = vt_get_msr,
+ .set_msr = vt_set_msr,
.get_segment_base = vmx_get_segment_base,
.get_segment = vmx_get_segment,
.set_segment = vmx_set_segment,
@@ -654,7 +690,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.apic_init_signal_blocked = vmx_apic_init_signal_blocked,
.migrate_timers = vmx_migrate_timers,
- .msr_filter_changed = vmx_msr_filter_changed,
+ .msr_filter_changed = vt_msr_filter_changed,
.complete_emulated_msr = kvm_complete_insn_gp,
.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 5f873fef9cb5..bb86b850889b 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1673,6 +1673,80 @@ void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
*error_code = 0;
}
+static bool tdx_is_emulated_kvm_msr(u32 index, bool write)
+{
+ switch (index) {
+ case MSR_KVM_POLL_CONTROL:
+ return true;
+ default:
+ return false;
+ }
+}
+
+bool tdx_has_emulated_msr(u32 index, bool write)
+{
+ switch (index) {
+ case MSR_IA32_UCODE_REV:
+ case MSR_IA32_ARCH_CAPABILITIES:
+ case MSR_IA32_POWER_CTL:
+ case MSR_MTRRcap:
+ case 0x200 ... 0x26f:
+ /* IA32_MTRR_PHYS{BASE, MASK}, IA32_MTRR_FIX*_* */
+ case MSR_IA32_CR_PAT:
+ case MSR_MTRRdefType:
+ case MSR_IA32_TSC_DEADLINE:
+ case MSR_IA32_MISC_ENABLE:
+ case MSR_PLATFORM_INFO:
+ case MSR_MISC_FEATURES_ENABLES:
+ case MSR_IA32_MCG_CAP:
+ case MSR_IA32_MCG_STATUS:
+ case MSR_IA32_MCG_CTL:
+ case MSR_IA32_MCG_EXT_CTL:
+ case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
+ case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
+ /* MSR_IA32_MCx_{CTL, STATUS, ADDR, MISC, CTL2} */
+ return true;
+ case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
+ /*
+ * x2APIC registers that are virtualized by the CPU can't be
+ * emulated, KVM doesn't have access to the virtual APIC page.
+ */
+ switch (index) {
+ case X2APIC_MSR(APIC_TASKPRI):
+ case X2APIC_MSR(APIC_PROCPRI):
+ case X2APIC_MSR(APIC_EOI):
+ case X2APIC_MSR(APIC_ISR) ... X2APIC_MSR(APIC_ISR + APIC_ISR_NR):
+ case X2APIC_MSR(APIC_TMR) ... X2APIC_MSR(APIC_TMR + APIC_ISR_NR):
+ case X2APIC_MSR(APIC_IRR) ... X2APIC_MSR(APIC_IRR + APIC_ISR_NR):
+ return false;
+ default:
+ return true;
+ }
+ case MSR_IA32_APICBASE:
+ case MSR_EFER:
+ return !write;
+ case 0x4b564d00 ... 0x4b564dff:
+ /* KVM custom MSRs */
+ return tdx_is_emulated_kvm_msr(index, write);
+ default:
+ return false;
+ }
+}
+
+int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
+{
+ if (tdx_has_emulated_msr(msr->index, false))
+ return kvm_get_msr_common(vcpu, msr);
+ return 1;
+}
+
+int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
+{
+ if (tdx_has_emulated_msr(msr->index, true))
+ return kvm_set_msr_common(vcpu, msr);
+ return 1;
+}
+
int tdx_dev_ioctl(void __user *argp)
{
struct kvm_tdx_capabilities __user *user_caps;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index b6960631b71d..4e0befb9d530 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -171,6 +171,9 @@ void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
void tdx_inject_nmi(struct kvm_vcpu *vcpu);
void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code);
+bool tdx_has_emulated_msr(u32 index, bool write);
+int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
+int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -213,6 +216,9 @@ static inline void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mo
static inline void tdx_inject_nmi(struct kvm_vcpu *vcpu) {}
static inline void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason, u64 *info1,
u64 *info2, u32 *intr_info, u32 *error_code) {}
+static inline bool tdx_has_emulated_msr(u32 index, bool write) { return false; }
+static inline int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) { return 1; }
+static inline int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) { return 1; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d18b6300b8d2..870041887ed9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -87,7 +87,6 @@
#include "trace.h"
#define MAX_IO_MSRS 256
-#define KVM_MAX_MCE_BANKS 32
struct kvm_caps kvm_caps __read_mostly = {
.supported_mce_cap = MCG_CTL_P | MCG_SER_P,
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index ef1282c7de8d..33a1a5341e78 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -8,6 +8,8 @@
#include "kvm_cache_regs.h"
#include "kvm_emulate.h"
+#define KVM_MAX_MCE_BANKS 32
+
bool __kvm_is_vm_type_supported(unsigned long type);
struct kvm_caps {
--
2.25.1
On 3/13/2023 1:55 AM, [email protected] wrote:
> diff --git a/arch/x86/kvm/vmx/tdx_arch.h b/arch/x86/kvm/vmx/tdx_arch.h
> new file mode 100644
> index 000000000000..942a0e561a7b
> --- /dev/null
> +++ b/arch/x86/kvm/vmx/tdx_arch.h
...
> +
> +#define TDG_VP_VMCALL_GET_TD_VM_CALL_INFO 0x10000
> +#define TDG_VP_VMCALL_MAP_GPA 0x10001
> +#define TDG_VP_VMCALL_GET_QUOTE 0x10002
> +#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
> +#define TDG_VP_VMCALL_SETUP_EVENT_NOTIFY_INTERRUPT 0x10004
TDX guest side implementation defines
/* TDX hypercall Leaf IDs */
#define TDVMCALL_MAP_GPA 0x10001
#define TDVMCALL_REPORT_FATAL_ERROR 0x10003
We need put these shared definitions between host and guest into some
shared header file.
On Mon, Mar 13, 2023 at 07:37:43PM +0800,
Xiaoyao Li <[email protected]> wrote:
> On 3/13/2023 1:55 AM, [email protected] wrote:
> > diff --git a/arch/x86/kvm/vmx/tdx_arch.h b/arch/x86/kvm/vmx/tdx_arch.h
> > new file mode 100644
> > index 000000000000..942a0e561a7b
> > --- /dev/null
> > +++ b/arch/x86/kvm/vmx/tdx_arch.h
> ...
> > +
> > +#define TDG_VP_VMCALL_GET_TD_VM_CALL_INFO 0x10000
> > +#define TDG_VP_VMCALL_MAP_GPA 0x10001
> > +#define TDG_VP_VMCALL_GET_QUOTE 0x10002
> > +#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
> > +#define TDG_VP_VMCALL_SETUP_EVENT_NOTIFY_INTERRUPT 0x10004
>
> TDX guest side implementation defines
>
> /* TDX hypercall Leaf IDs */
> #define TDVMCALL_MAP_GPA 0x10001
> #define TDVMCALL_REPORT_FATAL_ERROR 0x10003
>
> We need put these shared definitions between host and guest into some shared
> header file.
Good suggestion. Let me fix it.
--
Isaku Yamahata <[email protected]>
On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> +int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> +{
> + int r;
> +
> + if (!enable_ept) {
> + pr_warn("Cannot enable TDX with EPT disabled\n");
> + return -EINVAL;
> + }
> +
> + /* tdx_enable() in tdx_module_setup() requires cpus lock. */
> + cpus_read_lock();
> + /* TDX requires VMX. */
> + r = vmxon_all();
Why not using hardware_enable_all()?
> + if (!r) {
> + int cpu;
> +
> + /*
> + * Because tdx_cpu_enabel() acquire spin locks, on_each_cpu()
> + * can't be used.
> + */
> + for_each_online_cpu(cpu) {
> + if (smp_call_on_cpu(cpu, tdx_cpu_enable_cpu, NULL, false))
> + r = -EIO;
> + }
> + if (!r)
> + r = tdx_module_setup();
> + }
> + vmxoff_all();
> + cpus_read_unlock();
> +
> + return r;
> +}
I think you should use hardware_enable_all(), and just do something similar to
below in vmx_hardware_enable():
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 7eec0226d56a..b7b3f99c0095 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2504,6 +2504,15 @@ static int vmx_hardware_enable(void)
return r;
}
+ if (enable_tdx) {
+ r = tdx_cpu_enable();
+ if (r) {
+ cpu_vmxoff();
+ intel_pt_handle_vmx(0);
+ return r;
+ }
+ }
+
if (enable_ept)
ept_sync_global();
It handles two cases automatically:
1) When user wants to use TDX while loading KVM module, if above fails, then
hardware_enable_all() returns error, and you just give up initializing TDX
module and mark enable_tdx as false.
2) When a new cpu becomes online, and when TDX is being used by KVM, then if
above fails, it automatically rejects the CPU which isn't TDX-runnable although
it is VMX-runnable.
On Tue, Mar 14, 2023 at 02:38:06AM +0000,
"Huang, Kai" <[email protected]> wrote:
> On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> > +int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > +{
> > + int r;
> > +
> > + if (!enable_ept) {
> > + pr_warn("Cannot enable TDX with EPT disabled\n");
> > + return -EINVAL;
> > + }
> > +
> > + /* tdx_enable() in tdx_module_setup() requires cpus lock. */
> > + cpus_read_lock();
> > + /* TDX requires VMX. */
> > + r = vmxon_all();
>
> Why not using hardware_enable_all()?
>
> > + if (!r) {
> > + int cpu;
> > +
> > + /*
> > + * Because tdx_cpu_enabel() acquire spin locks, on_each_cpu()
> > + * can't be used.
> > + */
> > + for_each_online_cpu(cpu) {
> > + if (smp_call_on_cpu(cpu, tdx_cpu_enable_cpu, NULL, false))
> > + r = -EIO;
> > + }
> > + if (!r)
> > + r = tdx_module_setup();
> > + }
> > + vmxoff_all();
> > + cpus_read_unlock();
> > +
> > + return r;
> > +}
>
> I think you should use hardware_enable_all(), and just do something similar to
> below in vmx_hardware_enable():
The use of hardware_enable_all() make us circle back to refactoring KVM
hardware initialization topic. I'd like to stay away from it for now for TDX.
I find that vmxon_all() is unnecessary and we can move VMXON to
tdx_cpu_enable_cpu().
Here is the version of dropping vmxon_all().
From f8fa8fe9786f1c4d4a3b0af0d0228d2842984cba Mon Sep 17 00:00:00 2001
Message-Id: <f8fa8fe9786f1c4d4a3b0af0d0228d2842984cba.1678864879.git.isaku.yamahata@intel.com>
In-Reply-To: <d2aa2142665b8204b628232ab615c98090371c99.1678864879.git.isaku.yamahata@intel.com>
References: <d2aa2142665b8204b628232ab615c98090371c99.1678864879.git.isaku.yamahata@intel.com>
From: Isaku Yamahata <[email protected]>
Date: Tue, 22 Feb 2022 14:44:15 -0800
Subject: [PATCH] KVM: TDX: Initialize the TDX module when loading the
KVM intel kernel module
TDX requires several initialization steps for KVM to create guest TDs.
Detect CPU feature, enable VMX (TDX is based on VMX), detect the TDX module
availability, and initialize it.
There are several options on when to initialize the TDX module. A.) kernel
module loading time, B.) the first guest TD creation time. A.) was chosen.
With B.), a user may hit an error of the TDX initialization when trying to
create the first guest TD. The machine that fails to initialize the TDX
module can't boot any guest TD further. Such failure is undesirable and a
surprise because the user expects that the machine can accommodate guest
TD, but actually not. So A.) is better than B.).
Introduce a module parameter, kvm_intel.tdx, to explicitly enable TDX KVM
support. It's off by default to keep same behavior for those who don't use
TDX. Implement hardware_setup method to detect TDX feature of CPU and
initialize TDX module.
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/Makefile | 1 +
arch/x86/kvm/vmx/main.c | 18 +++++++++-
arch/x86/kvm/vmx/tdx.c | 74 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 7 ++++
arch/x86/kvm/vmx/x86_ops.h | 9 +++++
5 files changed, 108 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/kvm/vmx/tdx.c
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 0e894ae23cbc..4b01ab842ab7 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -25,6 +25,7 @@ kvm-$(CONFIG_KVM_SMM) += smm.o
kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
vmx/hyperv.o vmx/nested.o vmx/posted_intr.o vmx/main.o
kvm-intel-$(CONFIG_X86_SGX_KVM) += vmx/sgx.o
+kvm-intel-$(CONFIG_INTEL_TDX_HOST) += vmx/tdx.o
kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o \
svm/sev.o svm/hyperv.o
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 3f49e8e38b6b..5c9f5e00b3c4 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -6,6 +6,22 @@
#include "nested.h"
#include "pmu.h"
+static bool enable_tdx __ro_after_init;
+module_param_named(tdx, enable_tdx, bool, 0444);
+
+static __init int vt_hardware_setup(void)
+{
+ int ret;
+
+ ret = vmx_hardware_setup();
+ if (ret)
+ return ret;
+
+ enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
+
+ return 0;
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
( \
BIT(APICV_INHIBIT_REASON_DISABLE)| \
@@ -159,7 +175,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
- .hardware_setup = vmx_hardware_setup,
+ .hardware_setup = vt_hardware_setup,
.handle_intel_pt_intr = NULL,
.runtime_ops = &vt_x86_ops,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
new file mode 100644
index 000000000000..8d265d7ae6fb
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <asm/tdx.h>
+
+#include "capabilities.h"
+#include "x86_ops.h"
+#include "x86.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+static int __init tdx_module_setup(void)
+{
+ int ret;
+
+ ret = tdx_enable();
+ if (ret) {
+ pr_info("Failed to initialize TDX module.\n");
+ return ret;
+ }
+
+ pr_info("TDX is supported.\n");
+ return 0;
+}
+
+static int __init tdx_cpu_enable_cpu(void *unused)
+{
+ int r;
+
+ /*
+ * TDX requires VMX. Because thread can be migrated, keep VMXON on
+ * all online cpus until all TDX module initialization is done.
+ */
+ r = vmxon();
+ if (r)
+ return r;
+ return tdx_cpu_enable();
+}
+
+static void __init tdx_vmxoff_cpu(void *unused)
+{
+ WARN_ON_ONCE(cpu_vmxoff());
+}
+
+int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
+{
+ int cpu;
+ int r = 0;
+
+ if (!enable_ept) {
+ pr_warn("Cannot enable TDX with EPT disabled\n");
+ return -EINVAL;
+ }
+
+ /* tdx_enable() in tdx_module_setup() requires cpus lock. */
+ cpus_read_lock();
+ /*
+ * Because tdx_cpu_enable() acquires spin locks, on_each_cpu()
+ * can't be used.
+ */
+ for_each_online_cpu(cpu) {
+ if (smp_call_on_cpu(cpu, tdx_cpu_enable_cpu, NULL, false)) {
+ r = -EIO;
+ break;
+ }
+ }
+ if (!r)
+ r = tdx_module_setup();
+ on_each_cpu(tdx_vmxoff_cpu, NULL, 1);
+ cpus_read_unlock();
+
+ return r;
+}
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 3bbd07412f00..ce48e0bc9e00 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8123,6 +8123,13 @@ static unsigned int vmx_handle_intel_pt_intr(void)
return 1;
}
+__init int vmxon(void)
+{
+ if (cr4_read_shadow() & X86_CR4_VMXE)
+ return -EBUSY;
+ return kvm_cpu_vmxon(__pa(this_cpu_read(vmxarea)));
+}
+
static __init void vmx_setup_user_return_msrs(void)
{
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 051b5c4b5c2f..892c39f7d771 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -20,6 +20,9 @@ bool kvm_is_vmx_supported(void);
int __init vmx_init(void);
void vmx_exit(void);
+__init int vmxon(void);
+__init int vmx_hardware_setup(void);
+
extern struct kvm_x86_ops vt_x86_ops __initdata;
extern struct kvm_x86_init_ops vt_init_ops __initdata;
@@ -133,4 +136,10 @@ void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu);
#endif
void vmx_setup_mce(struct kvm_vcpu *vcpu);
+#ifdef CONFIG_INTEL_TDX_HOST
+int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
+#else
+static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
+#endif
+
#endif /* __KVM_X86_VMX_X86_OPS_H */
--
2.25.1
--
Isaku Yamahata <[email protected]>
> >
> > I think you should use hardware_enable_all(), and just do something similar to
> > below in vmx_hardware_enable():
>
> The use of hardware_enable_all() make us circle back to refactoring KVM
> hardware initialization topic. I'd like to stay away from it for now for TDX.
Sean's series to improve hardware enable has been merged to upstream already.
Can you elaborate what's the issue here?
[...]
> +static bool enable_tdx __ro_after_init;
> +module_param_named(tdx, enable_tdx, bool, 0444);
> +
> +static __init int vt_hardware_setup(void)
> +{
> + int ret;
> +
> + ret = vmx_hardware_setup();
> + if (ret)
> + return ret;
> +
> + enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
Unfortunately, the enable_tdx should also be protected by the cpus_read_lock(),
because CPU hotplug code path checks it too (as seen in your next patch).
> +
> + return 0;
> +}
> +
> #define VMX_REQUIRED_APICV_INHIBITS \
> ( \
> BIT(APICV_INHIBIT_REASON_DISABLE)| \
> @@ -159,7 +175,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> };
>
> struct kvm_x86_init_ops vt_init_ops __initdata = {
> - .hardware_setup = vmx_hardware_setup,
> + .hardware_setup = vt_hardware_setup,
> .handle_intel_pt_intr = NULL,
>
> .runtime_ops = &vt_x86_ops,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> new file mode 100644
> index 000000000000..8d265d7ae6fb
> --- /dev/null
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -0,0 +1,74 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/cpu.h>
> +
> +#include <asm/tdx.h>
> +
> +#include "capabilities.h"
> +#include "x86_ops.h"
> +#include "x86.h"
> +
> +#undef pr_fmt
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +static int __init tdx_module_setup(void)
> +{
> + int ret;
> +
> + ret = tdx_enable();
> + if (ret) {
> + pr_info("Failed to initialize TDX module.\n");
> + return ret;
> + }
> +
> + pr_info("TDX is supported.\n");
> + return 0;
> +}
> +
> +static int __init tdx_cpu_enable_cpu(void *unused)
> +{
> + int r;
> +
> + /*
> + * TDX requires VMX. Because thread can be migrated, keep VMXON on
> + * all online cpus until all TDX module initialization is done.
> + */
The second sentence in this comment should be somewhere else, but not here.
> + r = vmxon();
> + if (r)
> + return r;
> + return tdx_cpu_enable();
> +}
> +
> +static void __init tdx_vmxoff_cpu(void *unused)
> +{
> + WARN_ON_ONCE(cpu_vmxoff());
> +}
> +
> +int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> +{
> + int cpu;
> + int r = 0;
> +
> + if (!enable_ept) {
> + pr_warn("Cannot enable TDX with EPT disabled\n");
> + return -EINVAL;
> + }
> +
> + /* tdx_enable() in tdx_module_setup() requires cpus lock. */
> + cpus_read_lock();
> + /*
> + * Because tdx_cpu_enable() acquires spin locks, on_each_cpu()
> + * can't be used.
> + */
Here you have cpus_read_lock() protection, so tdx_cpu_enable() cannot be called
from CPU hotplug code path when you are doing here.
So, using on_each_cpu() to do tdx_cpu_enable() is OK here, because on one
particular cpu, when it already has taken the spinlock, it cannot receive IPI
anymore which can try to take the spinlock again.
> + for_each_online_cpu(cpu) {
> + if (smp_call_on_cpu(cpu, tdx_cpu_enable_cpu, NULL, false)) {
> + r = -EIO;
> + break;
> + }
> + }
> + if (!r)
> + r = tdx_module_setup();
> + on_each_cpu(tdx_vmxoff_cpu, NULL, 1);
> + cpus_read_unlock();
> +
> + return r;
> +}
I think you can merge next patch with this one because they are kinda related.
Putting them together allows people to review more easily.
On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> TDX requires to call a TDX initialization function per logical processor
> (LP) before the LP uses TDX. When CPU is onlined, call the TDX LP
> initialization API when cpu is onlined.
>
Double "when CPU is onlined".
> If it failed refuse onlininig of
> the cpu for simplicity instead of TDX avoiding the LP.
Sorry cannot understand this sentence, particularly, the "instead ..." part.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/kvm/vmx/main.c | 15 ++++++++++++++-
> arch/x86/kvm/vmx/tdx.c | 5 +++++
> arch/x86/kvm/vmx/x86_ops.h | 2 ++
> 3 files changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 5c9f5e00b3c4..d1c9c7f55050 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -9,6 +9,19 @@
> static bool enable_tdx __ro_after_init;
> module_param_named(tdx, enable_tdx, bool, 0444);
>
> +static int vt_hardware_enable(void)
> +{
> + int ret;
> +
> + ret = vmx_hardware_enable();
> + if (!ret && enable_tdx) {
> + ret = tdx_hardware_enable();
> + if (ret)
> + vmx_hardware_disable();
> + }
> + return ret;
> +}
> +
> static __init int vt_hardware_setup(void)
> {
> int ret;
> @@ -40,7 +53,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>
> .hardware_unsetup = vmx_hardware_unsetup,
>
> - .hardware_enable = vmx_hardware_enable,
> + .hardware_enable = vt_hardware_enable,
> .hardware_disable = vmx_hardware_disable,
> .has_emulated_msr = vmx_has_emulated_msr,
>
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index f3eb0138b60b..e51314bbb439 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -10,6 +10,11 @@
> #undef pr_fmt
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> +int tdx_hardware_enable(void)
> +{
> + return tdx_cpu_enable();
> +}
> +
> static int __init tdx_module_setup(void)
> {
> int ret;
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 0f200aead411..010d02c86ba4 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -139,8 +139,10 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
>
> #ifdef CONFIG_INTEL_TDX_HOST
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> +int tdx_hardware_enable(void);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> +static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> #endif
>
> #endif /* __KVM_X86_VMX_X86_OPS_H */
>
> > +static bool enable_tdx __ro_after_init;
> > +module_param_named(tdx, enable_tdx, bool, 0444);
> > +
> > +static __init int vt_hardware_setup(void)
> > +{
> > + int ret;
> > +
> > + ret = vmx_hardware_setup();
> > + if (ret)
> > + return ret;
> > +
> > + enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
>
> Unfortunately, the enable_tdx should also be protected by the
> cpus_read_lock(),
> because CPU hotplug code path checks it too (as seen in your next patch).
Sorry I was wrong. I forgot the CPU hotplug callbacks are registered in
kvm_init(), which happens after hardware_setup(), so the CPU hotplug code cannot
race with this hardware_setup() code here.
[...]
>
> I think you can merge next patch with this one because they are kinda related.
>
>
> Putting them together allows people to review more easily.
And perhaps this isn't necessary either.
On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> +
> +static inline bool is_td(struct kvm *kvm)
> +{
> + return kvm->arch.vm_type == KVM_X86_PROTECTED_VM;
> +}
> +
KVM_X86_PROTECTED_VM is defined in the next patch, which means this patch cannot
compile.
Also, why KVM_X86_PROTECTED_VM == TDX VM?
On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
>
> -static bool kvm_is_vm_type_supported(unsigned long type)
> +bool __kvm_is_vm_type_supported(unsigned long type)
> {
> return type == KVM_X86_DEFAULT_VM ||
> (type == KVM_X86_PROTECTED_VM &&
> IS_ENABLED(CONFIG_KVM_PROTECTED_VM) && tdp_enabled);
> }
> +EXPORT_SYMBOL_GPL(__kvm_is_vm_type_supported);
Where is CONFIG_KVM_PROTECTED_VM introduced?
On Wed, Mar 15, 2023 at 09:46:00AM +0000,
"Huang, Kai" <[email protected]> wrote:
>
> > >
> > > I think you should use hardware_enable_all(), and just do something similar to
> > > below in vmx_hardware_enable():
> >
> > The use of hardware_enable_all() make us circle back to refactoring KVM
> > hardware initialization topic. I'd like to stay away from it for now for TDX.
>
> Sean's series to improve hardware enable has been merged to upstream already.
I revised the patch and I can use hardware_enable_all().
> > + for_each_online_cpu(cpu) {
> > + if (smp_call_on_cpu(cpu, tdx_cpu_enable_cpu, NULL, false)) {
> > + r = -EIO;
> > + break;
> > + }
> > + }
> > + if (!r)
> > + r = tdx_module_setup();
> > + on_each_cpu(tdx_vmxoff_cpu, NULL, 1);
> > + cpus_read_unlock();
> > +
> > + return r;
> > +}
>
> I think you can merge next patch with this one because they are kinda related.
>
> Putting them together allows people to review more easily.
Finally I come up with the version that uses kvm_hardware_enable_all().
that doesn't issue cpus_read_lock().
I had to patch tdx_cpu_enable(). I'll reply to the patch itself.
From 38774fc6e2bc5f0eddd0a0ab035ba8e712ee5ff2 Mon Sep 17 00:00:00 2001
Message-Id: <38774fc6e2bc5f0eddd0a0ab035ba8e712ee5ff2.1678926122.git.isaku.yamahata@intel.com>
In-Reply-To: <d2aa2142665b8204b628232ab615c98090371c99.1678926122.git.isaku.yamahata@intel.com>
References: <d2aa2142665b8204b628232ab615c98090371c99.1678926122.git.isaku.yamahata@intel.com>
From: Isaku Yamahata <[email protected]>
Date: Tue, 22 Feb 2022 14:44:15 -0800
Subject: [PATCH] KVM: TDX: Initialize the TDX module when loading the
KVM intel kernel module
TDX requires several initialization steps for KVM to create guest TDs.
Detect CPU feature, enable VMX (TDX is based on VMX) on all online CPUs,
detect the TDX module availability, initialize it and disable VMX.
To enable VMX on all online CPUs, utilize kvm_hardware_enable_all() that
calls hardware_enable() methods. The method also initialize each CPU for
TDX. TDX requires to call a TDX initialization function per logical
processor (LP) before the LP uses TDX. When CPU is onlined, call the TDX
LP initialization API when cpu is onlined. If it failed refuse onlininig
of the cpu for simplicity instead of TDX avoiding the LP.
There are several options on when to initialize the TDX module. A.) kernel
module loading time, B.) the first guest TD creation time. A.) was chosen.
With B.), a user may hit an error of the TDX initialization when trying to
create the first guest TD. The machine that fails to initialize the TDX
module can't boot any guest TD further. Such failure is undesirable and a
surprise because the user expects that the machine can accommodate guest
TD, but actually not. So A.) is better than B.).
Introduce a module parameter, kvm_intel.tdx, to explicitly enable TDX KVM
support. It's off by default to keep same behavior for those who don't use
TDX. Implement hardware_setup method to detect TDX feature of CPU and
initialize TDX module.
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/kvm/Makefile | 1 +
arch/x86/kvm/vmx/main.c | 34 ++++++++++++++++++++++++++--
arch/x86/kvm/vmx/tdx.c | 46 ++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/x86_ops.h | 8 +++++++
arch/x86/kvm/x86.c | 10 +++++++++
5 files changed, 97 insertions(+), 2 deletions(-)
create mode 100644 arch/x86/kvm/vmx/tdx.c
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 0e894ae23cbc..4b01ab842ab7 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -25,6 +25,7 @@ kvm-$(CONFIG_KVM_SMM) += smm.o
kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
vmx/hyperv.o vmx/nested.o vmx/posted_intr.o vmx/main.o
kvm-intel-$(CONFIG_X86_SGX_KVM) += vmx/sgx.o
+kvm-intel-$(CONFIG_INTEL_TDX_HOST) += vmx/tdx.o
kvm-amd-y += svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o \
svm/sev.o svm/hyperv.o
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 3f49e8e38b6b..f7bfa9888d9e 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -6,6 +6,36 @@
#include "nested.h"
#include "pmu.h"
+static bool enable_tdx __ro_after_init;
+module_param_named(tdx, enable_tdx, bool, 0444);
+
+static int vt_hardware_enable(void)
+{
+ int ret;
+
+ ret = vmx_hardware_enable();
+ if (ret || !enable_tdx)
+ return ret;
+
+ ret = tdx_cpu_enable();
+ if (ret)
+ vmx_hardware_disable();
+ return ret;
+}
+
+static __init int vt_hardware_setup(void)
+{
+ int ret;
+
+ ret = vmx_hardware_setup();
+ if (ret)
+ return ret;
+
+ enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
+
+ return 0;
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
( \
BIT(APICV_INHIBIT_REASON_DISABLE)| \
@@ -24,7 +54,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.hardware_unsetup = vmx_hardware_unsetup,
- .hardware_enable = vmx_hardware_enable,
+ .hardware_enable = vt_hardware_enable,
.hardware_disable = vmx_hardware_disable,
.has_emulated_msr = vmx_has_emulated_msr,
@@ -159,7 +189,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
- .hardware_setup = vmx_hardware_setup,
+ .hardware_setup = vt_hardware_setup,
.handle_intel_pt_intr = NULL,
.runtime_ops = &vt_x86_ops,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
new file mode 100644
index 000000000000..f13fdf71430b
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <asm/tdx.h>
+
+#include "capabilities.h"
+#include "x86_ops.h"
+#include "x86.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+static int __init tdx_module_setup(void)
+{
+ int ret;
+
+ ret = tdx_enable();
+ if (ret) {
+ pr_info("Failed to initialize TDX module.\n");
+ return ret;
+ }
+
+ pr_info("TDX is supported.\n");
+ return 0;
+}
+
+int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
+{
+ int r = 0;
+
+ if (!enable_ept) {
+ pr_warn("Cannot enable TDX with EPT disabled\n");
+ return -EINVAL;
+ }
+
+ /* tdx_enable() in tdx_module_setup() requires cpus lock. */
+ cpus_read_lock();
+ r = kvm_hardware_enable_all();
+ if (!r) {
+ r = tdx_module_setup();
+ kvm_hardware_disable_all();
+ }
+ cpus_read_unlock();
+
+ return r;
+}
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 051b5c4b5c2f..f59e5197836a 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -20,6 +20,8 @@ bool kvm_is_vmx_supported(void);
int __init vmx_init(void);
void vmx_exit(void);
+__init int vmx_hardware_setup(void);
+
extern struct kvm_x86_ops vt_x86_ops __initdata;
extern struct kvm_x86_init_ops vt_init_ops __initdata;
@@ -133,4 +135,10 @@ void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu);
#endif
void vmx_setup_mce(struct kvm_vcpu *vcpu);
+#ifdef CONFIG_INTEL_TDX_HOST
+int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
+#else
+static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
+#endif
+
#endif /* __KVM_X86_VMX_X86_OPS_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2125fcaa3973..b264012a8478 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9435,6 +9435,16 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
kvm_init_pmu_capability(ops->pmu_ops);
+ /*
+ * TDX requires those methods to enable VMXON by
+ * kvm_hardware_enable/disable_all()
+ */
+ static_call_update(kvm_x86_check_processor_compatibility,
+ ops->runtime_ops->check_processor_compatibility);
+ static_call_update(kvm_x86_hardware_enable,
+ ops->runtime_ops->hardware_enable);
+ static_call_update(kvm_x86_hardware_disable,
+ ops->runtime_ops->hardware_disable);
r = ops->hardware_setup();
if (r != 0)
goto out_mmu_exit;
--
2.25.1
--
Isaku Yamahata <[email protected]>
On Sun, 2023-03-12 at 10:56 -0700, [email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> Because TDX virtualize cpuid[0x1].EDX[MTRR: bit 12] to fixed 1, guest TD
> thinks MTRR is supported. Although TDX supports only WB for private GPA,
> it's desirable to support MTRR for shared GPA. As guest access to MTRR
> MSRs causes #VE and KVM/x86 tracks the values of MTRR MSRs, the remining
> part is to implement get_mt_mask method for TDX for shared GPA.
>
> Pass around shared bit from kvm fault handler to get_mt_mask method so that
> it can determine if the gfn is shared or private.
>
I think we have an Xarray to query whether a given GFN is shared or private?
Can we use that?
> Implement get_mt_mask()
> following vmx case for shared GPA and return WB for private GPA.
> the existing vmx_get_mt_mask() can't be directly used as CPU state(CR0.CD)
> is protected. GFN passed to kvm_mtrr_check_gfn_range_consistency() should
> include shared bit.
>
> Suggested-by: Kai Huang <[email protected]>
I am not sure what is suggested by me?
I thought what I suggested is we should have a dedicated patch to handle MTRR
for TDX putting all related things together.
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> Changes from v11 to V12
> - Make common function for VMX and TDX
> - pass around shared bit from KVM fault handler to get_mt_mask method
> - updated commit message
> ---
> arch/x86/kvm/mmu/mmu.c | 7 ++++++-
> arch/x86/kvm/mmu/spte.c | 5 +++--
> arch/x86/kvm/mmu/spte.h | 2 +-
> arch/x86/kvm/vmx/common.h | 2 ++
> arch/x86/kvm/vmx/main.c | 11 ++++++++++-
> arch/x86/kvm/vmx/tdx.c | 17 +++++++++++++++++
> arch/x86/kvm/vmx/vmx.c | 5 +++--
> arch/x86/kvm/vmx/x86_ops.h | 2 ++
> 8 files changed, 44 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 6074aa09cd87..fb858594cfec 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -4569,7 +4569,12 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
> if (shadow_memtype_mask && kvm_arch_has_noncoherent_dma(vcpu->kvm)) {
> for ( ; fault->max_level > PG_LEVEL_4K; --fault->max_level) {
> int page_num = KVM_PAGES_PER_HPAGE(fault->max_level);
> - gfn_t base = gfn_round_for_level(fault->gfn,
> + /*
> + * kvm_mtrr_check_gfn_range_consistency() requires gfn
> + * including shared bit.
>
Why? MTRR MSRs should always contain the true GFN without shared bit, correct?
Then why kvm_mtrr_check_gfn_range_consistency() needs shared bit?
> fault->gfn is masked out with
> + * shared bit. So fault->gfn can't be used.
> + */
> + gfn_t base = gfn_round_for_level(gpa_to_gfn(fault->addr),
> fault->max_level);
>
> if (kvm_mtrr_check_gfn_range_consistency(vcpu, base, page_num))
> diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
> index 180907ef26c7..7adb0d00ec4b 100644
> --- a/arch/x86/kvm/mmu/spte.c
> +++ b/arch/x86/kvm/mmu/spte.c
> @@ -137,13 +137,14 @@ bool spte_has_volatile_bits(u64 spte)
>
> bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
> const struct kvm_memory_slot *slot,
> - unsigned int pte_access, gfn_t gfn, kvm_pfn_t pfn,
> + unsigned int pte_access, gfn_t gfn_including_shared, kvm_pfn_t pfn,
IMHO 'gfn_including_shared' is ugly, especially changing from 'gfn' in _THIS_
particular patch.
> u64 old_spte, bool prefetch, bool can_unsync,
> bool host_writable, u64 *new_spte)
> {
> int level = sp->role.level;
> u64 spte = SPTE_MMU_PRESENT_MASK;
> bool wrprot = false;
> + gfn_t gfn = gfn_including_shared & ~kvm_gfn_shared_mask(vcpu->kvm);
>
> WARN_ON_ONCE(!pte_access && !shadow_present_mask);
>
> @@ -191,7 +192,7 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
> spte |= PT_PAGE_SIZE_MASK;
>
> if (shadow_memtype_mask)
> - spte |= static_call(kvm_x86_get_mt_mask)(vcpu, gfn,
> + spte |= static_call(kvm_x86_get_mt_mask)(vcpu, gfn_including_shared,
> kvm_is_mmio_pfn(pfn));
> if (host_writable)
> spte |= shadow_host_writable_mask;
> diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
> index 41973fe6bc22..62280c4b8c81 100644
> --- a/arch/x86/kvm/mmu/spte.h
> +++ b/arch/x86/kvm/mmu/spte.h
> @@ -481,7 +481,7 @@ bool spte_has_volatile_bits(u64 spte);
>
> bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
> const struct kvm_memory_slot *slot,
> - unsigned int pte_access, gfn_t gfn, kvm_pfn_t pfn,
> + unsigned int pte_access, gfn_t gfn_including_shared, kvm_pfn_t pfn,
> u64 old_spte, bool prefetch, bool can_unsync,
> bool host_writable, u64 *new_spte);
> u64 make_huge_page_split_spte(struct kvm *kvm, u64 huge_spte,
> diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
> index 235908f3e044..422b24af7fc1 100644
> --- a/arch/x86/kvm/vmx/common.h
> +++ b/arch/x86/kvm/vmx/common.h
> @@ -6,6 +6,8 @@
>
> #include "mmu.h"
>
> +u8 __vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio, bool check_cr0_cd);
> +
> static inline int __vmx_handle_ept_violation(struct kvm_vcpu *vcpu, gpa_t gpa,
> unsigned long exit_qualification)
> {
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 902b57506291..55001b34e1f0 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -3,6 +3,7 @@
>
> #include "x86_ops.h"
> #include "mmu.h"
> +#include "common.h"
> #include "vmx.h"
> #include "nested.h"
> #include "mmu.h"
> @@ -228,6 +229,14 @@ static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
> vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
> }
>
> +static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> +{
> + if (is_td_vcpu(vcpu))
> + return tdx_get_mt_mask(vcpu, gfn, is_mmio);
> +
> + return __vmx_get_mt_mask(vcpu, gfn, is_mmio, true);
> +}
> +
> static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> {
> if (!is_td(kvm))
> @@ -348,7 +357,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>
> .set_tss_addr = vmx_set_tss_addr,
> .set_identity_map_addr = vmx_set_identity_map_addr,
> - .get_mt_mask = vmx_get_mt_mask,
> + .get_mt_mask = vt_get_mt_mask,
>
> .get_exit_info = vmx_get_exit_info,
>
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 6ab7580de69c..b7b4ab60f96d 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -5,6 +5,7 @@
>
> #include "capabilities.h"
> #include "x86_ops.h"
> +#include "common.h"
> #include "tdx.h"
> #include "vmx.h"
> #include "x86.h"
> @@ -350,6 +351,22 @@ int tdx_vm_init(struct kvm *kvm)
> return 0;
> }
>
> +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> +{
> + /* TDX private GPA is always WB. */
> + if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
> + /* MMIO is only for shared GPA. */
> + WARN_ON_ONCE(is_mmio);
> + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
> + }
> +
> + /* Drop shared bit as MTRR doesn't know about shared bit. */
> + gfn = kvm_gfn_to_private(vcpu->kvm, gfn);
> +
> + /* As TDX enforces CR0.CD to 0, pass check_cr0_cd = false. */
> + return __vmx_get_mt_mask(vcpu, gfn, is_mmio, false);
> +}
Do you know whether there's any use case of non-coherent device assignment to
TDX guest?
IMHO, we should just disallow TDX guest to support non-coherent device
assignment, so that we can just return WB for both private and shared.
If we support non-coherent device assignment, then if guest sets private memory
to non-WB memory, it believes the memory type is non-WB, but in fact TDX always
map private memory as WB.
Will this be a problem, i.e. if assigned device can DMA to private memory
directly in the future?
> +
> int tdx_vcpu_create(struct kvm_vcpu *vcpu)
> {
> /*
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 23321b2208ae..b8d8f7fbeb69 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -7568,7 +7568,8 @@ int vmx_vm_init(struct kvm *kvm)
> return 0;
> }
>
> -u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> +u8 __vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio,
> + bool check_cr0_cd)
> {
> u8 cache;
>
> @@ -7596,7 +7597,7 @@ u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))
> return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;
>
> - if (kvm_read_cr0(vcpu) & X86_CR0_CD) {
> + if (check_cr0_cd && kvm_read_cr0(vcpu) & X86_CR0_CD) {
> if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED))
> cache = MTRR_TYPE_WRBACK;
> else
On Wed, Mar 15, 2023 at 10:44:57AM +0000,
"Huang, Kai" <[email protected]> wrote:
> On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> >
> > -static bool kvm_is_vm_type_supported(unsigned long type)
> > +bool __kvm_is_vm_type_supported(unsigned long type)
> > {
> > return type == KVM_X86_DEFAULT_VM ||
> > (type == KVM_X86_PROTECTED_VM &&
> > IS_ENABLED(CONFIG_KVM_PROTECTED_VM) && tdp_enabled);
> > }
> > +EXPORT_SYMBOL_GPL(__kvm_is_vm_type_supported);
>
> Where is CONFIG_KVM_PROTECTED_VM introduced?
UPM patch series.
KVM: x86: Add support for "protected VMs" that can utilize private memory
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index fa195797461e..e8f334b0ff2c 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1245,6 +1245,7 @@ enum kvm_apicv_inhibit {
};
struct kvm_arch {
+ unsigned long vm_type;
unsigned long n_used_mmu_pages;
unsigned long n_requested_mmu_pages;
unsigned long n_max_mmu_pages;
@@ -2049,6 +2050,12 @@ void kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd);
void kvm_configure_mmu(bool enable_tdp, int tdp_forced_root_level,
int tdp_max_root_level, int tdp_huge_page_level);
+#ifdef CONFIG_KVM_PRIVATE_MEM
+#define kvm_arch_has_private_mem(kvm) ((kvm)->arch.vm_type != KVM_X86_DEFAULT_VM)
+#else
+#define kvm_arch_has_private_mem(kvm) false
+#endif
+
static inline u16 kvm_read_ldt(void)
{
u16 ldt;
...
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 7f467fe05d42..6afbfbb32d56 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -559,4 +559,7 @@ struct kvm_pmu_event_filter {
#define KVM_VCPU_TSC_CTRL 0 /* control group for the timestamp counter (TSC) */
#define KVM_VCPU_TSC_OFFSET 0 /* attribute for the TSC offset */
+#define KVM_X86_DEFAULT_VM 0
+#define KVM_X86_PROTECTED_VM 1
+
#endif /* _ASM_X86_KVM_H */
...
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index ed84bb3cd82d..718010600956 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -78,6 +78,17 @@ config KVM_WERROR
If in doubt, say "N".
+config KVM_PROTECTED_VM
+ bool "Enable support for KVM-protected VMs"
+ depends on EXPERT
+ depends on X86_64
+ select KVM_GENERIC_PRIVATE_MEM
+ help
+ Enable support KVM-protected VMs. Currently 'protected' means the VM
+ can be backed with restricted/private memory.
+
+ If unsure, say "N".
+
config KVM_INTEL
tristate "KVM for Intel (and compatible) processo
--
Isaku Yamahata <[email protected]>
On Wed, Mar 15, 2023 at 10:42:09AM +0000,
"Huang, Kai" <[email protected]> wrote:
> On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> > +
> > +static inline bool is_td(struct kvm *kvm)
> > +{
> > + return kvm->arch.vm_type == KVM_X86_PROTECTED_VM;
> > +}
> > +
>
> KVM_X86_PROTECTED_VM is defined in the next patch, which means this patch cannot
> compile.
>
> Also, why KVM_X86_PROTECTED_VM == TDX VM?
This part needs to be resolved.
Use KVM_X86_PROTECTED_VM as TDX VM or new type KVM_X86_TDX_VM or other way
to specify VM type.
Given pKVM is coming, dedicated VM type seems better. I'll switch it to
KVM_X86_TDX_VM next respin.
--
Isaku Yamahata <[email protected]>
On Thu, 2023-03-16 at 08:41 -0700, Isaku Yamahata wrote:
> On Wed, Mar 15, 2023 at 10:42:09AM +0000,
> "Huang, Kai" <[email protected]> wrote:
>
> > On Sun, 2023-03-12 at 10:55 -0700, [email protected] wrote:
> > > +
> > > +static inline bool is_td(struct kvm *kvm)
> > > +{
> > > + return kvm->arch.vm_type == KVM_X86_PROTECTED_VM;
> > > +}
> > > +
> >
> > KVM_X86_PROTECTED_VM is defined in the next patch, which means this patch cannot
> > compile.
Oh I see your patch only added this type to tools/.../asm/kvm.h
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -559,4 +559,7 @@ struct kvm_pmu_event_filter {
#define KVM_VCPU_TSC_CTRL 0 /* control group for the timestamp counter (TSC) */
#define KVM_VCPU_TSC_OFFSET 0 /* attribute for the TSC offset */
+#define KVM_X86_DEFAULT_VM 0
+#define KVM_X86_PROTECTED_VM 1
+
So this one has already been in UPM series.
But I thought Sean had a comment saying we should not add such definition to
header file under tools/:
Even it needs to be added, it should be in the relevant patch in UPM series, but
not here.
> >
> > Also, why KVM_X86_PROTECTED_VM == TDX VM?
>
> This part needs to be resolved.
> Use KVM_X86_PROTECTED_VM as TDX VM or new type KVM_X86_TDX_VM or other way
> to specify VM type.
> Given pKVM is coming, dedicated VM type seems better. I'll switch it to
> KVM_X86_TDX_VM next respin.
> --
> Isaku Yamahata <[email protected]>
I'll leave to Sean and Paolo.
On 3/13/2023 1:55, [email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> As the first step to create TDX guest, create/destroy VM struct. Assign
> TDX private Host Key ID (HKID) to the TDX guest for memory encryption and
> allocate extra pages for the TDX guest. On destruction, free allocated
> pages, and HKID.
>
> Before tearing down private page tables, TDX requires some resources of the
> guest TD to be destroyed (i.e. HKID must have been reclaimed, etc). Add
> flush_shadow_all_private callback before tearing down private page tables
> for it.
>
> Add vm_free() of kvm_x86_ops hook at the end of kvm_arch_destroy_vm()
> because some per-VM TDX resources, e.g. TDR, need to be freed after other
> TDX resources, e.g. HKID, were freed.
>
> Co-developed-by: Kai Huang <[email protected]>
> Signed-off-by: Kai Huang <[email protected]>
> Signed-off-by: Sean Christopherson <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
>
> ---
> Changes v11 -> v12:
> - use cpu_feature_enabled().
>
> Changes v10 -> v11:
> - Fix doule free in tdx_vm_free() by setting NULL.
> - replace struct tdx_td_page tdr and tdcs from struct kvm_tdx with
> unsigned long
> ---
> arch/x86/include/asm/kvm-x86-ops.h | 2 +
> arch/x86/include/asm/kvm_host.h | 2 +
> arch/x86/kvm/vmx/main.c | 35 ++-
> arch/x86/kvm/vmx/tdx.c | 442 ++++++++++++++++++++++++++++-
> arch/x86/kvm/vmx/tdx.h | 6 +-
> arch/x86/kvm/vmx/x86_ops.h | 9 +
> arch/x86/kvm/x86.c | 8 +
> 7 files changed, 498 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> index 7522c193f2b4..c30d2d2ad686 100644
> --- a/arch/x86/include/asm/kvm-x86-ops.h
> +++ b/arch/x86/include/asm/kvm-x86-ops.h
> @@ -24,7 +24,9 @@ KVM_X86_OP(is_vm_type_supported)
> KVM_X86_OP_OPTIONAL(max_vcpus);
> KVM_X86_OP_OPTIONAL(vm_enable_cap)
> KVM_X86_OP(vm_init)
> +KVM_X86_OP_OPTIONAL(flush_shadow_all_private)
> KVM_X86_OP_OPTIONAL(vm_destroy)
> +KVM_X86_OP_OPTIONAL(vm_free)
> KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
> KVM_X86_OP(vcpu_create)
> KVM_X86_OP(vcpu_free)
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index d98d61e5213d..15f7c0d45082 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1566,7 +1566,9 @@ struct kvm_x86_ops {
> unsigned int vm_size;
> int (*vm_enable_cap)(struct kvm *kvm, struct kvm_enable_cap *cap);
> int (*vm_init)(struct kvm *kvm);
> + void (*flush_shadow_all_private)(struct kvm *kvm);
> void (*vm_destroy)(struct kvm *kvm);
> + void (*vm_free)(struct kvm *kvm);
>
> /* Create, but do not attach this VCPU */
> int (*vcpu_precreate)(struct kvm *kvm);
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 68bb320d0b6d..08ed6fc8cc3d 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -62,14 +62,41 @@ static int vt_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> return -EINVAL;
> }
>
> +static void vt_hardware_unsetup(void)
> +{
> + if (enable_tdx)
> + tdx_hardware_unsetup();
> + vmx_hardware_unsetup();
> +}
> +
> static int vt_vm_init(struct kvm *kvm)
> {
> if (is_td(kvm))
> - return -EOPNOTSUPP; /* Not ready to create guest TD yet. */
> + return tdx_vm_init(kvm);
>
> return vmx_vm_init(kvm);
> }
>
> +static void vt_flush_shadow_all_private(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + tdx_mmu_release_hkid(kvm);
> +}
> +
> +static void vt_vm_destroy(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + return;
> +
> + vmx_vm_destroy(kvm);
> +}
> +
> +static void vt_vm_free(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + tdx_vm_free(kvm);
> +}
> +
> static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> {
> if (!is_td(kvm))
> @@ -94,7 +121,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>
> .check_processor_compatibility = vmx_check_processor_compat,
>
> - .hardware_unsetup = vmx_hardware_unsetup,
> + .hardware_unsetup = vt_hardware_unsetup,
>
> .hardware_enable = vt_hardware_enable,
> .hardware_disable = vmx_hardware_disable,
> @@ -105,7 +132,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .vm_size = sizeof(struct kvm_vmx),
> .vm_enable_cap = vt_vm_enable_cap,
> .vm_init = vt_vm_init,
> - .vm_destroy = vmx_vm_destroy,
> + .flush_shadow_all_private = vt_flush_shadow_all_private,
> + .vm_destroy = vt_vm_destroy,
> + .vm_free = vt_vm_free,
>
> .vcpu_precreate = vmx_vcpu_precreate,
> .vcpu_create = vmx_vcpu_create,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 8b02e605cfb5..3ede8a726b47 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -5,8 +5,9 @@
>
> #include "capabilities.h"
> #include "x86_ops.h"
> -#include "x86.h"
> #include "tdx.h"
> +#include "tdx_ops.h"
> +#include "x86.h"
>
> #undef pr_fmt
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> @@ -46,11 +47,276 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> return r;
> }
>
> +struct tdx_info {
> + u8 nr_tdcs_pages;
> +};
> +
> +/* Info about the TDX module. */
> +static struct tdx_info tdx_info;
> +
> +/*
> + * Some TDX SEAMCALLs (TDH.MNG.CREATE, TDH.PHYMEM.CACHE.WB,
> + * TDH.MNG.KEY.RECLAIMID, TDH.MNG.KEY.FREEID etc) tries to acquire a global lock
> + * internally in TDX module. If failed, TDX_OPERAND_BUSY is returned without
> + * spinning or waiting due to a constraint on execution time. It's caller's
> + * responsibility to avoid race (or retry on TDX_OPERAND_BUSY). Use this mutex
> + * to avoid race in TDX module because the kernel knows better about scheduling.
> + */
> +static DEFINE_MUTEX(tdx_lock);
> +static struct mutex *tdx_mng_key_config_lock;
> +
> +static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
> +{
> + return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
> +}
> +
> +static inline bool is_td_created(struct kvm_tdx *kvm_tdx)
> +{
> + return kvm_tdx->tdr_pa;
> +}
> +
> +static inline void tdx_hkid_free(struct kvm_tdx *kvm_tdx)
> +{
> + tdx_guest_keyid_free(kvm_tdx->hkid);
> + kvm_tdx->hkid = 0;
> +}
> +
> +static inline bool is_hkid_assigned(struct kvm_tdx *kvm_tdx)
> +{
> + return kvm_tdx->hkid > 0;
> +}
> +
> int tdx_hardware_enable(void)
> {
> return tdx_cpu_enable();
> }
>
> +static void tdx_clear_page(unsigned long page_pa)
> +{
> + const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
> + void *page = __va(page_pa);
> + unsigned long i;
> +
> + if (!cpu_feature_enabled(X86_FEATURE_MOVDIR64B)) {
> + clear_page(page);
> + return;
> + }
> +
> + /*
> + * Zeroing the page is only necessary for systems with MKTME-i:
> + * when re-assign one page from old keyid to a new keyid, MOVDIR64B is
> + * required to clear/write the page with new keyid to prevent integrity
> + * error when read on the page with new keyid.
> + *
> + * clflush doesn't flush cache with HKID set.
> + * The cache line could be poisoned (even without MKTME-i), clear the
> + * poison bit.
> + */
> + for (i = 0; i < PAGE_SIZE; i += 64)
> + movdir64b(page + i, zero_page);
> + /*
> + * MOVDIR64B store uses WC buffer. Prevent following memory reads
> + * from seeing potentially poisoned cache.
> + */
> + __mb();
> +}
> +
> +static int tdx_reclaim_page(hpa_t pa, bool do_wb, u16 hkid)
> +{
> + struct tdx_module_output out;
> + u64 err;
> +
> + do {
> + err = tdh_phymem_page_reclaim(pa, &out);
> + /*
> + * TDH.PHYMEM.PAGE.RECLAIM is allowed only when TD is shutdown.
> + * state. i.e. destructing TD.
> + * TDH.PHYMEM.PAGE.RECLAIM requires TDR and target page.
> + * Because we're destructing TD, it's rare to contend with TDR.
> + */
> + } while (err == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_RCX));
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_PHYMEM_PAGE_RECLAIM, err, &out);
> + return -EIO;
> + }
> +
> + if (do_wb) {
> + /*
> + * Only TDR page gets into this path. No contention is expected
> + * because of the last page of TD.
> + */
> + err = tdh_phymem_page_wbinvd(set_hkid_to_hpa(pa, hkid));
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_PHYMEM_PAGE_WBINVD, err, NULL);
> + return -EIO;
> + }
> + }
> +
> + tdx_clear_page(pa);
> + return 0;
> +}
> +
> +static void tdx_reclaim_td_page(unsigned long td_page_pa)
> +{
> + if (!td_page_pa)
> + return;
> + /*
> + * TDCX are being reclaimed. TDX module maps TDCX with HKID
> + * assigned to the TD. Here the cache associated to the TD
> + * was already flushed by TDH.PHYMEM.CACHE.WB before here, So
> + * cache doesn't need to be flushed again.
> + */
> + if (tdx_reclaim_page(td_page_pa, false, 0))
> + /*
> + * Leak the page on failure:
> + * tdx_reclaim_page() returns an error if and only if there's an
> + * unexpected, fatal error, e.g. a SEAMCALL with bad params,
> + * incorrect concurrency in KVM, a TDX Module bug, etc.
> + * Retrying at a later point is highly unlikely to be
> + * successful.
> + * No log here as tdx_reclaim_page() already did.
> + */
> + return;
> + free_page((unsigned long)__va(td_page_pa));
> +}
> +
> +static int tdx_do_tdh_phymem_cache_wb(void *param)
> +{
> + u64 err = 0;
> +
> + do {
> + err = tdh_phymem_cache_wb(!!err);
> + } while (err == TDX_INTERRUPTED_RESUMABLE);
> +
> + /* Other thread may have done for us. */
> + if (err == TDX_NO_HKID_READY_TO_WBCACHE)
> + err = TDX_SUCCESS;
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_PHYMEM_CACHE_WB, err, NULL);
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +void tdx_mmu_release_hkid(struct kvm *kvm)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + cpumask_var_t packages;
> + bool cpumask_allocated;
> + u64 err;
> + int ret;
> + int i;
> +
> + if (!is_hkid_assigned(kvm_tdx))
> + return;
> +
> + if (!is_td_created(kvm_tdx))
> + goto free_hkid;
> +
> + cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
> + cpus_read_lock();
> + for_each_online_cpu(i) {
> + if (cpumask_allocated &&
> + cpumask_test_and_set_cpu(topology_physical_package_id(i),
> + packages))
> + continue;
> +
> + /*
> + * We can destroy multiple the guest TDs simultaneously.
> + * Prevent tdh_phymem_cache_wb from returning TDX_BUSY by
> + * serialization.
> + */
> + mutex_lock(&tdx_lock);
> + ret = smp_call_on_cpu(i, tdx_do_tdh_phymem_cache_wb, NULL, 1);
> + mutex_unlock(&tdx_lock);
> + if (ret)
> + break;
> + }
> + cpus_read_unlock();
> + free_cpumask_var(packages);
> +
> + mutex_lock(&tdx_lock);
> + err = tdh_mng_key_freeid(kvm_tdx->tdr_pa);
> + mutex_unlock(&tdx_lock);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_KEY_FREEID, err, NULL);
> + pr_err("tdh_mng_key_freeid failed. HKID %d is leaked.\n",
> + kvm_tdx->hkid);
> + return;
> + }
> +
> +free_hkid:
> + tdx_hkid_free(kvm_tdx);
> +}
> +
> +void tdx_vm_free(struct kvm *kvm)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + int i;
> +
> + /* Can't reclaim or free TD pages if teardown failed. */
> + if (is_hkid_assigned(kvm_tdx))
> + return;
> +
> + if (kvm_tdx->tdcs_pa) {
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++)
> + tdx_reclaim_td_page(kvm_tdx->tdcs_pa[i]);
> + kfree(kvm_tdx->tdcs_pa);
> + kvm_tdx->tdcs_pa = NULL;
> + }
> +
> + if (!kvm_tdx->tdr_pa)
> + return;
> + /*
> + * TDX module maps TDR with TDX global HKID. TDX module may access TDR
> + * while operating on TD (Especially reclaiming TDCS). Cache flush with
> + * TDX global HKID is needed.
> + */
> + if (tdx_reclaim_page(kvm_tdx->tdr_pa, true, tdx_global_keyid))
> + return;
> +
> + free_page((unsigned long)__va(kvm_tdx->tdr_pa));
> + kvm_tdx->tdr_pa = 0;
> +}
> +
> +static int tdx_do_tdh_mng_key_config(void *param)
> +{
> + hpa_t *tdr_p = param;
> + u64 err;
> +
> + do {
> + err = tdh_mng_key_config(*tdr_p);
> +
> + /*
> + * If it failed to generate a random key, retry it because this
> + * is typically caused by an entropy error of the CPU's random
> + * number generator.
> + */
> + } while (err == TDX_KEY_GENERATION_FAILED);
> +
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_KEY_CONFIG, err, NULL);
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +static int __tdx_td_init(struct kvm *kvm);
> +
> +int tdx_vm_init(struct kvm *kvm)
> +{
> + /*
> + * TDX has its own limit of the number of vcpus in addition to
> + * KVM_MAX_VCPUS.
> + */
> + kvm->max_vcpus = min(kvm->max_vcpus, TDX_MAX_VCPUS);
> +
> + /* Place holder for TDX specific logic. */
> + return __tdx_td_init(kvm);
> +}
> +
> int tdx_dev_ioctl(void __user *argp)
> {
> struct kvm_tdx_capabilities __user *user_caps;
> @@ -102,6 +368,160 @@ int tdx_dev_ioctl(void __user *argp)
> return 0;
> }
>
> +static int __tdx_td_init(struct kvm *kvm)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + cpumask_var_t packages;
> + unsigned long *tdcs_pa = NULL;
> + unsigned long tdr_pa = 0;
> + unsigned long va;
> + int ret, i;
> + u64 err;
> +
> + ret = tdx_guest_keyid_alloc();
> + if (ret < 0)
> + return ret;
> + kvm_tdx->hkid = ret;
> +
> + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> + if (!va)
> + goto free_hkid;
> + tdr_pa = __pa(va);
> +
> + tdcs_pa = kcalloc(tdx_info.nr_tdcs_pages, sizeof(*kvm_tdx->tdcs_pa),
> + GFP_KERNEL_ACCOUNT | __GFP_ZERO);
> + if (!tdcs_pa)
> + goto free_tdr;
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> + if (!va)
> + goto free_tdcs;
> + tdcs_pa[i] = __pa(va);
> + }
> +
> + if (!zalloc_cpumask_var(&packages, GFP_KERNEL)) {
> + ret = -ENOMEM;
> + goto free_tdcs;
> + }
> + cpus_read_lock();
> + /*
> + * Need at least one CPU of the package to be online in order to
> + * program all packages for host key id. Check it.
> + */
> + for_each_present_cpu(i)
> + cpumask_set_cpu(topology_physical_package_id(i), packages);
> + for_each_online_cpu(i)
> + cpumask_clear_cpu(topology_physical_package_id(i), packages);
> + if (!cpumask_empty(packages)) {
> + ret = -EIO;
> + /*
> + * Because it's hard for human operator to figure out the
> + * reason, warn it.
> + */
> + pr_warn("All packages need to have online CPU to create TD. Online CPU and retry.\n");
> + goto free_packages;
> + }
> +
> + /*
> + * Acquire global lock to avoid TDX_OPERAND_BUSY:
> + * TDH.MNG.CREATE and other APIs try to lock the global Key Owner
> + * Table (KOT) to track the assigned TDX private HKID. It doesn't spin
> + * to acquire the lock, returns TDX_OPERAND_BUSY instead, and let the
> + * caller to handle the contention. This is because of time limitation
> + * usable inside the TDX module and OS/VMM knows better about process
> + * scheduling.
> + *
> + * APIs to acquire the lock of KOT:
> + * TDH.MNG.CREATE, TDH.MNG.KEY.FREEID, TDH.MNG.VPFLUSHDONE, and
> + * TDH.PHYMEM.CACHE.WB.
> + */
> + mutex_lock(&tdx_lock);
> + err = tdh_mng_create(tdr_pa, kvm_tdx->hkid);
In the latest (March 2023 ver.) Intel® TDX Module v1.5 ABI Specification, error
code 0x80000203 represents TDX_RND_NO_ENTROPY:
Random number generation (e.g., RDRAND or RDSEED) failed because the hardware
random number generator did not have enough entropy. The caller should retry the
operation.
> + mutex_unlock(&tdx_lock);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_CREATE, err, NULL);
> + ret = -EIO;
> + goto free_packages;
> + }
> + kvm_tdx->tdr_pa = tdr_pa;
> +
> + for_each_online_cpu(i) {
> + int pkg = topology_physical_package_id(i);
> +
> + if (cpumask_test_and_set_cpu(pkg, packages))
> + continue;
> +
> + /*
> + * Program the memory controller in the package with an
> + * encryption key associated to a TDX private host key id
> + * assigned to this TDR. Concurrent operations on same memory
> + * controller results in TDX_OPERAND_BUSY. Avoid this race by
> + * mutex.
> + */
> + mutex_lock(&tdx_mng_key_config_lock[pkg]);
> + ret = smp_call_on_cpu(i, tdx_do_tdh_mng_key_config,
> + &kvm_tdx->tdr_pa, true);
> + mutex_unlock(&tdx_mng_key_config_lock[pkg]);
> + if (ret)
> + break;
> + }
> + cpus_read_unlock();
> + free_cpumask_var(packages);
> + if (ret)
> + goto teardown;
> +
> + kvm_tdx->tdcs_pa = tdcs_pa;
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> + err = tdh_mng_addcx(kvm_tdx->tdr_pa, tdcs_pa[i]);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_ADDCX, err, NULL);
> + for (i++; i < tdx_info.nr_tdcs_pages; i++) {
> + free_page((unsigned long)__va(tdcs_pa[i]));
> + tdcs_pa[i] = 0;
> + }
> + ret = -EIO;
> + goto teardown;
> + }
> + }
> +
> + /*
> + * Note, TDH_MNG_INIT cannot be invoked here. TDH_MNG_INIT requires a dedicated
> + * ioctl() to define the configure CPUID values for the TD.
> + */
> + return 0;
> +
> + /*
> + * The sequence for freeing resources from a partially initialized TD
> + * varies based on where in the initialization flow failure occurred.
> + * Simply use the full teardown and destroy, which naturally play nice
> + * with partial initialization.
> + */
> +teardown:
> + tdx_mmu_release_hkid(kvm);
> + tdx_vm_free(kvm);
> + return ret;
> +
> +free_packages:
> + cpus_read_unlock();
> + free_cpumask_var(packages);
> +free_tdcs:
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> + if (tdcs_pa[i])
> + free_page((unsigned long)__va(tdcs_pa[i]));
> + }
> + kfree(tdcs_pa);
> + kvm_tdx->tdcs_pa = NULL;
> +
> +free_tdr:
> + if (tdr_pa)
> + free_page((unsigned long)__va(tdr_pa));
> + kvm_tdx->tdr_pa = 0;
> +free_hkid:
> + if (is_hkid_assigned(kvm_tdx))
> + tdx_hkid_free(kvm_tdx);
> + return ret;
> +}
> +
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> {
> struct kvm_tdx_cmd tdx_cmd;
> @@ -142,9 +562,11 @@ static int __init tdx_module_setup(void)
> return ret;
> }
>
> - /* Sanitary check just in case. */
> tdsysinfo = tdx_get_sysinfo();
> WARN_ON(tdsysinfo->num_cpuid_config > TDX_MAX_NR_CPUID_CONFIGS);
> + tdx_info = (struct tdx_info) {
> + .nr_tdcs_pages = tdsysinfo->tdcs_base_size / PAGE_SIZE,
> + };
>
> pr_info("TDX is supported.\n");
> return 0;
> @@ -163,6 +585,8 @@ static int __init tdx_cpu_enable_cpu(void *unused)
>
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> {
> + int max_pkgs;
> + int i;
> int r;
>
> if (!enable_ept) {
> @@ -170,6 +594,14 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> return -EINVAL;
> }
>
> + max_pkgs = topology_max_packages();
> + tdx_mng_key_config_lock = kcalloc(max_pkgs, sizeof(*tdx_mng_key_config_lock),
> + GFP_KERNEL);
> + if (!tdx_mng_key_config_lock)
> + return -ENOMEM;
> + for (i = 0; i < max_pkgs; i++)
> + mutex_init(&tdx_mng_key_config_lock[i]);
> +
> /* tdx_enable() in tdx_module_setup() requires cpus lock. */
> cpus_read_lock();
> /* TDX requires VMX. */
> @@ -193,3 +625,9 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
>
> return r;
> }
> +
> +void tdx_hardware_unsetup(void)
> +{
> + /* kfree accepts NULL. */
> + kfree(tdx_mng_key_config_lock);
> +}
> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
> index 3860aa351bd9..4b790503e43e 100644
> --- a/arch/x86/kvm/vmx/tdx.h
> +++ b/arch/x86/kvm/vmx/tdx.h
> @@ -8,7 +8,11 @@
>
> struct kvm_tdx {
> struct kvm kvm;
> - /* TDX specific members follow. */
> +
> + unsigned long tdr_pa;
> + unsigned long *tdcs_pa;
> +
> + int hkid;
> };
>
> struct vcpu_tdx {
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 8118647aa8ca..8f87eeeab97c 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -139,19 +139,28 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
>
> #ifdef CONFIG_INTEL_TDX_HOST
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> +void tdx_hardware_unsetup(void);
> int tdx_hardware_enable(void);
> bool tdx_is_vm_type_supported(unsigned long type);
> int tdx_dev_ioctl(void __user *argp);
>
> int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
> +int tdx_vm_init(struct kvm *kvm);
> +void tdx_mmu_release_hkid(struct kvm *kvm);
> +void tdx_vm_free(struct kvm *kvm);
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> +static inline void tdx_hardware_unsetup(void) {}
> static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
>
> static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
> +static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
> +static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
> +static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
> +static inline void tdx_vm_free(struct kvm *kvm) {}
> static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
> #endif
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 7b02dd40ef21..89fd8074c20c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -12398,6 +12398,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
> kvm_page_track_cleanup(kvm);
> kvm_xen_destroy_vm(kvm);
> kvm_hv_destroy_vm(kvm);
> + static_call_cond(kvm_x86_vm_free)(kvm);
> }
>
> static void memslot_rmap_free(struct kvm_memory_slot *slot)
> @@ -12710,6 +12711,13 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
>
> void kvm_arch_flush_shadow_all(struct kvm *kvm)
> {
> + /*
> + * kvm_mmu_zap_all() zaps both private and shared page tables. Before
> + * tearing down private page tables, TDX requires some TD resources to
> + * be destroyed (i.e. keyID must have been reclaimed, etc). Invoke
> + * kvm_x86_flush_shadow_all_private() for this.
> + */
> + static_call_cond(kvm_x86_flush_shadow_all_private)(kvm);
> kvm_mmu_zap_all(kvm);
> }
>
On Friday, March 24, 2023 10:28 AM, Wang, Lei wrote:
> > +static int __tdx_td_init(struct kvm *kvm) {
> > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > + cpumask_var_t packages;
> > + unsigned long *tdcs_pa = NULL;
> > + unsigned long tdr_pa = 0;
> > + unsigned long va;
> > + int ret, i;
> > + u64 err;
> > +
> > + ret = tdx_guest_keyid_alloc();
> > + if (ret < 0)
> > + return ret;
> > + kvm_tdx->hkid = ret;
> > +
> > + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> > + if (!va)
> > + goto free_hkid;
> > + tdr_pa = __pa(va);
> > +
> > + tdcs_pa = kcalloc(tdx_info.nr_tdcs_pages, sizeof(*kvm_tdx->tdcs_pa),
> > + GFP_KERNEL_ACCOUNT | __GFP_ZERO);
> > + if (!tdcs_pa)
> > + goto free_tdr;
> > + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> > + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> > + if (!va)
> > + goto free_tdcs;
> > + tdcs_pa[i] = __pa(va);
> > + }
> > +
> > + if (!zalloc_cpumask_var(&packages, GFP_KERNEL)) {
> > + ret = -ENOMEM;
> > + goto free_tdcs;
> > + }
> > + cpus_read_lock();
> > + /*
> > + * Need at least one CPU of the package to be online in order to
> > + * program all packages for host key id. Check it.
> > + */
> > + for_each_present_cpu(i)
> > + cpumask_set_cpu(topology_physical_package_id(i), packages);
> > + for_each_online_cpu(i)
> > + cpumask_clear_cpu(topology_physical_package_id(i),
> packages);
> > + if (!cpumask_empty(packages)) {
> > + ret = -EIO;
> > + /*
> > + * Because it's hard for human operator to figure out the
> > + * reason, warn it.
> > + */
> > + pr_warn("All packages need to have online CPU to create TD.
> Online CPU and retry.\n");
> > + goto free_packages;
> > + }
> > +
> > + /*
> > + * Acquire global lock to avoid TDX_OPERAND_BUSY:
> > + * TDH.MNG.CREATE and other APIs try to lock the global Key Owner
> > + * Table (KOT) to track the assigned TDX private HKID. It doesn't spin
> > + * to acquire the lock, returns TDX_OPERAND_BUSY instead, and let the
> > + * caller to handle the contention. This is because of time limitation
> > + * usable inside the TDX module and OS/VMM knows better about
> process
> > + * scheduling.
> > + *
> > + * APIs to acquire the lock of KOT:
> > + * TDH.MNG.CREATE, TDH.MNG.KEY.FREEID, TDH.MNG.VPFLUSHDONE,
> and
> > + * TDH.PHYMEM.CACHE.WB.
> > + */
> > + mutex_lock(&tdx_lock);
> > + err = tdh_mng_create(tdr_pa, kvm_tdx->hkid);
>
> In the latest (March 2023 ver.) Intel® TDX Module v1.5 ABI Specification, error
> code 0x80000203 represents TDX_RND_NO_ENTROPY:
This patchset is written for what's documented in the TDX 1.0 spec.
We'll update it for 1.5 later.
Sorry for late reply.
>
> +static bool enable_tdx __ro_after_init;
> +module_param_named(tdx, enable_tdx, bool, 0444);
> +
> +static int vt_hardware_enable(void)
> +{
> + int ret;
> +
> + ret = vmx_hardware_enable();
> + if (ret || !enable_tdx)
> + return ret;
> +
> + ret = tdx_cpu_enable();
> + if (ret)
> + vmx_hardware_disable();
> + return ret;
> +}
> +
> +static __init int vt_hardware_setup(void)
> +{
> + int ret;
> +
> + ret = vmx_hardware_setup();
> + if (ret)
> + return ret;
> +
> + enable_tdx = enable_tdx && !tdx_hardware_setup(&vt_x86_ops);
> +
> + return 0;
> +}
> +
> #define VMX_REQUIRED_APICV_INHIBITS \
> ( \
> BIT(APICV_INHIBIT_REASON_DISABLE)| \
> @@ -24,7 +54,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>
> .hardware_unsetup = vmx_hardware_unsetup,
>
> - .hardware_enable = vmx_hardware_enable,
> + .hardware_enable = vt_hardware_enable,
> .hardware_disable = vmx_hardware_disable,
> .has_emulated_msr = vmx_has_emulated_msr,
>
> @@ -159,7 +189,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> };
>
> struct kvm_x86_init_ops vt_init_ops __initdata = {
> - .hardware_setup = vmx_hardware_setup,
> + .hardware_setup = vt_hardware_setup,
> .handle_intel_pt_intr = NULL,
>
> .runtime_ops = &vt_x86_ops,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> new file mode 100644
> index 000000000000..f13fdf71430b
> --- /dev/null
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -0,0 +1,46 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/cpu.h>
> +
> +#include <asm/tdx.h>
> +
> +#include "capabilities.h"
> +#include "x86_ops.h"
> +#include "x86.h"
> +
> +#undef pr_fmt
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +static int __init tdx_module_setup(void)
> +{
> + int ret;
> +
> + ret = tdx_enable();
> + if (ret) {
> + pr_info("Failed to initialize TDX module.\n");
> + return ret;
> + }
> +
> + pr_info("TDX is supported.\n");
Both pr_info()s are not required, because tdx_enable() internally prints them.
> + return 0;
> +}
> +
> +int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> +{
> + int r = 0;
> +
> + if (!enable_ept) {
> + pr_warn("Cannot enable TDX with EPT disabled\n");
> + return -EINVAL;
> + }
> +
> + /* tdx_enable() in tdx_module_setup() requires cpus lock. */
> + cpus_read_lock();
> + r = kvm_hardware_enable_all();
> + if (!r) {
> + r = tdx_module_setup();
> + kvm_hardware_disable_all();
> + }
> + cpus_read_unlock();
> +
> + return r;
> +}
>
[...]
> #endif /* __KVM_X86_VMX_X86_OPS_H */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 2125fcaa3973..b264012a8478 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -9435,6 +9435,16 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
>
> kvm_init_pmu_capability(ops->pmu_ops);
>
> + /*
> + * TDX requires those methods to enable VMXON by
> + * kvm_hardware_enable/disable_all()
> + */
> + static_call_update(kvm_x86_check_processor_compatibility,
> + ops->runtime_ops->check_processor_compatibility);
> + static_call_update(kvm_x86_hardware_enable,
> + ops->runtime_ops->hardware_enable);
> + static_call_update(kvm_x86_hardware_disable,
> + ops->runtime_ops->hardware_disable);
> r = ops->hardware_setup();
> if (r != 0)
> goto out_mmu_exit;
Hmm.. I think this is ugly. Perhaps we should never do any
static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
called before kvm_ops_update() and may update vendor's kvm_x86_ops.
So probably use hardware_enable_all() in hardware_setup() is a bad idea.
I think we have below options on how to handle:
1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
something like below:
int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
{
...
cpus_read_lock();
r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
if (!r)
r = tdx_module_setup();
on_each_cpu(vt_x86_ops.hardware_disable, ...);
cpus_read_unlock();
...
}
But this doesn't clean up nicely when there's some particular cpus fail to do
hardware_enable(). To clean up nicely, we do need additional things similar to
the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
hardware_enable() successfully.
2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
code self-contained. But this would require exposing kvm_x86_ops as symbol,
which isn't nice either.
3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
after kvm_ops_update().
Personally, I think 3) perhaps is the most elegant one, but not sure whether
Sean/Paolo has any opinion.
On Sun, 12 Mar 2023 10:55:35 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> A VMM interacts with the TDX module using a new instruction (SEAMCALL). A
> TDX VMM uses SEAMCALLs where a VMX VMM would have directly interacted with
^ This sentence is little bit confusing, it can be removed. The next two sentences have stated the situation clearly.
> VMX instructions. For instance, a TDX VMM does not have full access to the
> VM control structure corresponding to VMX VMCS. Instead, a VMM induces the
> TDX module to act on behalf via SEAMCALLs.
>
> Export __seamcall and define C wrapper functions for SEAMCALLs for
> readability.
>
> Some SEAMCALL APIs donates host pages to TDX module or guest TD and the
> donated pages are encrypted. Some of such SEAMCALLs flush cache lines
^ "some of" can be removed.
> (typically by movdir64b instruction), some don't. Those that doesn't
> clear cache lines require the VMM to flush the cache lines to avoid cache
> line alias.
>
> Signed-off-by: Sean Christopherson <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/include/asm/tdx.h | 4 +
> arch/x86/kvm/vmx/tdx_ops.h | 202 +++++++++++++++++++++++++++++++
> arch/x86/virt/vmx/tdx/seamcall.S | 2 +
> arch/x86/virt/vmx/tdx/tdx.h | 3 -
> 4 files changed, 208 insertions(+), 3 deletions(-)
> create mode 100644 arch/x86/kvm/vmx/tdx_ops.h
>
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index 112a5b9bd5cd..6c01ab572c1f 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -104,10 +104,14 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
> bool platform_tdx_enabled(void);
> int tdx_cpu_enable(void);
> int tdx_enable(void);
> +u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
> + struct tdx_module_output *out);
> #else /* !CONFIG_INTEL_TDX_HOST */
> static inline bool platform_tdx_enabled(void) { return false; }
> static inline int tdx_cpu_enable(void) { return -EINVAL; }
> static inline int tdx_enable(void) { return -EINVAL; }
> +static inline u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
> + struct tdx_module_output *out) { return TDX_SEAMCALL_UD; };
> #endif /* CONFIG_INTEL_TDX_HOST */
>
> #endif /* !__ASSEMBLY__ */
> diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h
> new file mode 100644
> index 000000000000..70e569838e1c
> --- /dev/null
> +++ b/arch/x86/kvm/vmx/tdx_ops.h
> @@ -0,0 +1,202 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* constants/data definitions for TDX SEAMCALLs */
> +
> +#ifndef __KVM_X86_TDX_OPS_H
> +#define __KVM_X86_TDX_OPS_H
> +
> +#include <linux/compiler.h>
> +
> +#include <asm/cacheflush.h>
> +#include <asm/asm.h>
> +#include <asm/kvm_host.h>
> +
> +#include "tdx_errno.h"
> +#include "tdx_arch.h"
> +#include "x86.h"
> +
> +static inline u64 kvm_seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
> + struct tdx_module_output *out)
> +{
> + u64 ret;
> +
> + ret = __seamcall(op, rcx, rdx, r8, r9, out);
> + if (ret == TDX_SEAMCALL_UD) {
> + /*
> + * TDX requires VMXON or #UD. In the case of reboot or kexec,
> + * VMX is made off (VMXOFF) by kvm reboot notifier,
> + * kvm_reboot(), while TDs are still running. The callers check
> + * the returned error and complain. Suppress it by returning 0.
> + */
> + kvm_spurious_fault();
> + return 0;
> + }
> + return ret;
> +}
> +
> +static inline u64 tdh_mng_addcx(hpa_t tdr, hpa_t addr)
> +{
> + clflush_cache_range(__va(addr), PAGE_SIZE);
> + return kvm_seamcall(TDH_MNG_ADDCX, addr, tdr, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mem_page_add(hpa_t tdr, gpa_t gpa, hpa_t hpa, hpa_t source,
> + struct tdx_module_output *out)
> +{
> + clflush_cache_range(__va(hpa), PAGE_SIZE);
> + return kvm_seamcall(TDH_MEM_PAGE_ADD, gpa, tdr, hpa, source, out);
> +}
> +
> +static inline u64 tdh_mem_sept_add(hpa_t tdr, gpa_t gpa, int level, hpa_t page,
> + struct tdx_module_output *out)
> +{
> + clflush_cache_range(__va(page), PAGE_SIZE);
> + return kvm_seamcall(TDH_MEM_SEPT_ADD, gpa | level, tdr, page, 0, out);
> +}
> +
> +static inline u64 tdh_mem_sept_remove(hpa_t tdr, gpa_t gpa, int level,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MEM_SEPT_REMOVE, gpa | level, tdr, 0, 0, out);
> +}
> +
> +static inline u64 tdh_vp_addcx(hpa_t tdvpr, hpa_t addr)
> +{
> + clflush_cache_range(__va(addr), PAGE_SIZE);
> + return kvm_seamcall(TDH_VP_ADDCX, addr, tdvpr, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mem_page_relocate(hpa_t tdr, gpa_t gpa, hpa_t hpa,
> + struct tdx_module_output *out)
> +{
> + clflush_cache_range(__va(hpa), PAGE_SIZE);
> + return kvm_seamcall(TDH_MEM_PAGE_RELOCATE, gpa, tdr, hpa, 0, out);
> +}
> +
> +static inline u64 tdh_mem_page_aug(hpa_t tdr, gpa_t gpa, hpa_t hpa,
> + struct tdx_module_output *out)
> +{
> + clflush_cache_range(__va(hpa), PAGE_SIZE);
> + return kvm_seamcall(TDH_MEM_PAGE_AUG, gpa, tdr, hpa, 0, out);
> +}
> +
> +static inline u64 tdh_mem_range_block(hpa_t tdr, gpa_t gpa, int level,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MEM_RANGE_BLOCK, gpa | level, tdr, 0, 0, out);
> +}
> +
> +static inline u64 tdh_mng_key_config(hpa_t tdr)
> +{
> + return kvm_seamcall(TDH_MNG_KEY_CONFIG, tdr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mng_create(hpa_t tdr, int hkid)
> +{
> + clflush_cache_range(__va(tdr), PAGE_SIZE);
> + return kvm_seamcall(TDH_MNG_CREATE, tdr, hkid, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_vp_create(hpa_t tdr, hpa_t tdvpr)
> +{
> + clflush_cache_range(__va(tdvpr), PAGE_SIZE);
> + return kvm_seamcall(TDH_VP_CREATE, tdvpr, tdr, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mng_rd(hpa_t tdr, u64 field, struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MNG_RD, tdr, field, 0, 0, out);
> +}
> +
> +static inline u64 tdh_mr_extend(hpa_t tdr, gpa_t gpa,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MR_EXTEND, gpa, tdr, 0, 0, out);
> +}
> +
> +static inline u64 tdh_mr_finalize(hpa_t tdr)
> +{
> + return kvm_seamcall(TDH_MR_FINALIZE, tdr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_vp_flush(hpa_t tdvpr)
> +{
> + return kvm_seamcall(TDH_VP_FLUSH, tdvpr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mng_vpflushdone(hpa_t tdr)
> +{
> + return kvm_seamcall(TDH_MNG_VPFLUSHDONE, tdr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mng_key_freeid(hpa_t tdr)
> +{
> + return kvm_seamcall(TDH_MNG_KEY_FREEID, tdr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mng_init(hpa_t tdr, hpa_t td_params,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MNG_INIT, tdr, td_params, 0, 0, out);
> +}
> +
> +static inline u64 tdh_vp_init(hpa_t tdvpr, u64 rcx)
> +{
> + return kvm_seamcall(TDH_VP_INIT, tdvpr, rcx, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_vp_rd(hpa_t tdvpr, u64 field,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_VP_RD, tdvpr, field, 0, 0, out);
> +}
> +
> +static inline u64 tdh_mng_key_reclaimid(hpa_t tdr)
> +{
> + return kvm_seamcall(TDH_MNG_KEY_RECLAIMID, tdr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_phymem_page_reclaim(hpa_t page,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_PHYMEM_PAGE_RECLAIM, page, 0, 0, 0, out);
> +}
> +
> +static inline u64 tdh_mem_page_remove(hpa_t tdr, gpa_t gpa, int level,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MEM_PAGE_REMOVE, gpa | level, tdr, 0, 0, out);
> +}
> +
> +static inline u64 tdh_sys_lp_shutdown(void)
> +{
> + return kvm_seamcall(TDH_SYS_LP_SHUTDOWN, 0, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mem_track(hpa_t tdr)
> +{
> + return kvm_seamcall(TDH_MEM_TRACK, tdr, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_mem_range_unblock(hpa_t tdr, gpa_t gpa, int level,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_MEM_RANGE_UNBLOCK, gpa | level, tdr, 0, 0, out);
> +}
> +
> +static inline u64 tdh_phymem_cache_wb(bool resume)
> +{
> + return kvm_seamcall(TDH_PHYMEM_CACHE_WB, resume ? 1 : 0, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_phymem_page_wbinvd(hpa_t page)
> +{
> + return kvm_seamcall(TDH_PHYMEM_PAGE_WBINVD, page, 0, 0, 0, NULL);
> +}
> +
> +static inline u64 tdh_vp_wr(hpa_t tdvpr, u64 field, u64 val, u64 mask,
> + struct tdx_module_output *out)
> +{
> + return kvm_seamcall(TDH_VP_WR, tdvpr, field, val, mask, out);
> +}
> +
> +#endif /* __KVM_X86_TDX_OPS_H */
> diff --git a/arch/x86/virt/vmx/tdx/seamcall.S b/arch/x86/virt/vmx/tdx/seamcall.S
> index f81be6b9c133..b90a7fe05494 100644
> --- a/arch/x86/virt/vmx/tdx/seamcall.S
> +++ b/arch/x86/virt/vmx/tdx/seamcall.S
> @@ -1,5 +1,6 @@
> /* SPDX-License-Identifier: GPL-2.0 */
> #include <linux/linkage.h>
> +#include <asm/export.h>
> #include <asm/frame.h>
>
> #include "tdxcall.S"
> @@ -50,3 +51,4 @@ SYM_FUNC_START(__seamcall)
> FRAME_END
> RET
> SYM_FUNC_END(__seamcall)
> +EXPORT_SYMBOL_GPL(__seamcall)
> diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
> index 48f830087e7e..4e497f202586 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.h
> +++ b/arch/x86/virt/vmx/tdx/tdx.h
> @@ -144,7 +144,4 @@ struct tdmr_info_list {
> int max_tdmrs; /* How many 'tdmr_info's are allocated */
> };
>
> -struct tdx_module_output;
> -u64 __seamcall(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
> - struct tdx_module_output *out);
Better move this part to a correct place.
> #endif
On Sun, 12 Mar 2023 10:55:38 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> TDX private host key id (HKID) is assigned to guest TD. The memory
> controller encrypts guest TD memory with the assigned TDX HKID. Add helper
> functions to allocate/free TDX private HKID so that TDX KVM can manage it.
>
^ This sentence should go to the below paragraph, which is "problem/way to go"
paragraph. For "background" paragraph, you can talk more about the usage of
HKID, like global/private HKID. Then you don't need to introduce them again in
the below paragraph and just talk about the solution.
> Also export the global TDX private HKID that is used to encrypt TDX module,
> its memory and some dynamic data (TDR). When VMM releasing encrypted page
> to reuse it, the page needs to be flushed with the used HKID. VMM needs
> the global TDX private HKID to flush such pages.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/include/asm/tdx.h | 12 ++++++++++++
> arch/x86/virt/vmx/tdx/tdx.c | 34 +++++++++++++++++++++++++++++++++-
> 2 files changed, 45 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index 6c01ab572c1f..7d99a48a98cc 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -104,6 +104,16 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
> bool platform_tdx_enabled(void);
> int tdx_cpu_enable(void);
> int tdx_enable(void);
> +/*
> + * Key id globally used by TDX module: TDX module maps TDR with this TDX global
> + * key id. TDR includes key id assigned to the TD. Then TDX module maps other
> + * TD-related pages with the assigned key id. TDR requires this TDX global key
> + * id for cache flush unlike other TD-related pages.
> + */
> +extern u32 tdx_global_keyid __ro_after_init;
> +int tdx_guest_keyid_alloc(void);
> +void tdx_guest_keyid_free(int keyid);
> +
> u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
> struct tdx_module_output *out);
> #else /* !CONFIG_INTEL_TDX_HOST */
> @@ -112,6 +122,8 @@ static inline int tdx_cpu_enable(void) { return -EINVAL; }
> static inline int tdx_enable(void) { return -EINVAL; }
> static inline u64 __seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
> struct tdx_module_output *out) { return TDX_SEAMCALL_UD; };
> +static inline int tdx_guest_keyid_alloc(void) { return -EOPNOTSUPP; }
> +static inline void tdx_guest_keyid_free(int keyid) { }
> #endif /* CONFIG_INTEL_TDX_HOST */
>
> #endif /* !__ASSEMBLY__ */
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index ee94a7327d93..3251fdf74667 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -33,7 +33,8 @@
> #include <asm/tdx.h>
> #include "tdx.h"
>
> -static u32 tdx_global_keyid __ro_after_init;
> +u32 tdx_global_keyid __ro_after_init;
> +EXPORT_SYMBOL_GPL(tdx_global_keyid);
> static u32 tdx_guest_keyid_start __ro_after_init;
> static u32 tdx_nr_guest_keyids __ro_after_init;
>
> @@ -138,6 +139,31 @@ static struct notifier_block tdx_memory_nb = {
> .notifier_call = tdx_memory_notifier,
> };
>
> +/* TDX KeyID pool */
> +static DEFINE_IDA(tdx_guest_keyid_pool);
> +
> +int tdx_guest_keyid_alloc(void)
> +{
> + if (WARN_ON_ONCE(!tdx_guest_keyid_start || !tdx_nr_guest_keyids))
> + return -EINVAL;
> +
> + /* The first keyID is reserved for the global key. */
> + return ida_alloc_range(&tdx_guest_keyid_pool, tdx_guest_keyid_start + 1,
> + tdx_guest_keyid_start + tdx_nr_guest_keyids - 1,
> + GFP_KERNEL);
> +}
> +EXPORT_SYMBOL_GPL(tdx_guest_keyid_alloc);
> +
> +void tdx_guest_keyid_free(int keyid)
> +{
> + /* keyid = 0 is reserved. */
> + if (WARN_ON_ONCE(keyid <= 0))
> + return;
> +
> + ida_free(&tdx_guest_keyid_pool, keyid);
> +}
> +EXPORT_SYMBOL_GPL(tdx_guest_keyid_free);
> +
> static int __init tdx_init(void)
> {
> u32 tdx_keyid_start, nr_tdx_keyids;
> @@ -1218,6 +1244,12 @@ static int init_tdx_module(void)
> if (ret)
> goto out_free_pamts;
>
> + /*
> + * Reserve the first TDX KeyID as global KeyID to protect
> + * TDX module metadata.
> + */
> + tdx_global_keyid = tdx_keyid_start;
> +
> /* Initialize TDMRs to complete the TDX module initialization */
> ret = init_tdmrs(&tdmr_list);
>
On Thu, Mar 16, 2023 at 10:38:02AM +0000,
"Huang, Kai" <[email protected]> wrote:
> On Sun, 2023-03-12 at 10:56 -0700, [email protected] wrote:
> > From: Isaku Yamahata <[email protected]>
> >
> > Because TDX virtualize cpuid[0x1].EDX[MTRR: bit 12] to fixed 1, guest TD
> > thinks MTRR is supported. Although TDX supports only WB for private GPA,
> > it's desirable to support MTRR for shared GPA. As guest access to MTRR
> > MSRs causes #VE and KVM/x86 tracks the values of MTRR MSRs, the remining
> > part is to implement get_mt_mask method for TDX for shared GPA.
> >
> > Pass around shared bit from kvm fault handler to get_mt_mask method so that
> > it can determine if the gfn is shared or private.
> >
>
> I think we have an Xarray to query whether a given GFN is shared or private?
> Can we use that?
>
> > Implement get_mt_mask()
> > following vmx case for shared GPA and return WB for private GPA.
> > the existing vmx_get_mt_mask() can't be directly used as CPU state(CR0.CD)
> > is protected. GFN passed to kvm_mtrr_check_gfn_range_consistency() should
> > include shared bit.
> >
> > Suggested-by: Kai Huang <[email protected]>
>
> I am not sure what is suggested by me?
>
> I thought what I suggested is we should have a dedicated patch to handle MTRR
> for TDX putting all related things together.
Sure. After looking at the specs, my conclusion is that guest TD can't update
MTRR reliably. Because MTRR update requires to disable cache(CR0.CR=1), cache
flush, and tlb flush. (SDM 3a 12.11.7: MTRR maintenance programming interface)
Linux implements MTRR update logic according to it.
While TDX enforces CR0.CD=0, trying to set CR0.CD=1 results in #GP. At the
same time, it reports that MTRR is available via cpuid. So I come up with the
followings.
- MTRRCap(RO): report no feature available
SMRR=0: SMRR interface unsupported
WC=0: write combining unsupported
FIX=0: Fixed range registers unsupported
VCNT=0: number of variable range regitsers = 0
- MTRRDefType(R/W): Only writeback even with reset state.
E=1: enable MTRR (E=0 means all memory is UC.)
FE=0: disable fixed range MTRRs
type: default memory type=writeback
Accept write this value. Other value results in #GP.
- Fixed range MTRR
#GP as fixed range MTRRs is reported as unsupported
- Variable range MTRRs
#GP as the number of variable range MTRRs is reported as zero
> > +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> > +{
> > + /* TDX private GPA is always WB. */
> > + if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
> > + /* MMIO is only for shared GPA. */
> > + WARN_ON_ONCE(is_mmio);
> > + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
> > + }
> > +
> > + /* Drop shared bit as MTRR doesn't know about shared bit. */
> > + gfn = kvm_gfn_to_private(vcpu->kvm, gfn);
> > +
> > + /* As TDX enforces CR0.CD to 0, pass check_cr0_cd = false. */
> > + return __vmx_get_mt_mask(vcpu, gfn, is_mmio, false);
> > +}
>
>
> Do you know whether there's any use case of non-coherent device assignment to
> TDX guest?
>
> IMHO, we should just disallow TDX guest to support non-coherent device
> assignment, so that we can just return WB for both private and shared.
>
> If we support non-coherent device assignment, then if guest sets private memory
> to non-WB memory, it believes the memory type is non-WB, but in fact TDX always
> map private memory as WB.
>
> Will this be a problem, i.e. if assigned device can DMA to private memory
> directly in the future?
MTRR is legacy feature and PAT replaced it. We can rely on guest to use PAT.
Here is the new patch for MTRR.
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -229,6 +229,14 @@ static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
}
+static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+{
+ if (is_td_vcpu(vcpu))
+ return tdx_get_mt_mask(vcpu, gfn, is_mmio);
+
+ return vmx_get_mt_mask(vcpu, gfn, is_mmio);
+}
+
static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
{
if (!is_td(kvm))
@@ -349,7 +357,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.set_tss_addr = vmx_set_tss_addr,
.set_identity_map_addr = vmx_set_identity_map_addr,
- .get_mt_mask = vmx_get_mt_mask,
+ .get_mt_mask = vt_get_mt_mask,
.get_exit_info = vmx_get_exit_info,
diff -u b/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
--- b/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -347,6 +347,25 @@
return 0;
}
+u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
+{
+ /* TDX private GPA is always WB. */
+ if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
+ /* MMIO is only for shared GPA. */
+ WARN_ON_ONCE(is_mmio);
+ return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
+ }
+
+ if (is_mmio)
+ return MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT;
+
+ if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))
+ return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;
+
+ /* TDX enforces CR0.CD = 0 and KVM MTRR emulation enforces writeback. */
+ return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
+}
+
int tdx_vcpu_create(struct kvm_vcpu *vcpu)
{
/*
@@ -1256,6 +1275,45 @@
return ret;
}
+static int tdx_vcpu_init_mtrr(struct kvm_vcpu *vcpu)
+{
+ struct msr_data msr;
+ int ret;
+ int i;
+
+ /*
+ * To avoid confusion with reporting VNCT = 0, explicitly disable
+ * vaiale-range reisters.
+ */
+ for (i = 0; i < KVM_NR_VAR_MTRR; i++) {
+ /* phymask */
+ msr = (struct msr_data) {
+ .host_initiated = true,
+ .index = 0x200 + 2 * i + 1,
+ .data = 0, /* valid = 0 to disable. */
+ };
+ ret = kvm_set_msr_common(vcpu, &msr);
+ if (ret)
+ return -EINVAL;
+ }
+
+ /* Set MTRR to use writeback on reset. */
+ msr = (struct msr_data) {
+ .host_initiated = true,
+ .index = MSR_MTRRdefType,
+ /*
+ * Set E(enable MTRR)=1, FE(enable fixed range MTRR)=0, default
+ * type=writeback on reset to avoid UC. Note E=0 means all
+ * memory is UC.
+ */
+ .data = (1 << 11) | MTRR_TYPE_WRBACK,
+ };
+ ret = kvm_set_msr_common(vcpu, &msr);
+ if (ret)
+ return -EINVAL;
+ return 0;
+}
+
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp)
{
struct msr_data apic_base_msr;
@@ -1293,6 +1351,10 @@
if (kvm_set_apic_base(vcpu, &apic_base_msr))
return -EINVAL;
+ ret = tdx_vcpu_init_mtrr(vcpu);
+ if (ret)
+ return ret;
+
ret = tdx_td_vcpu_init(vcpu, (u64)cmd.data);
if (ret)
return ret;
@@ -1676,7 +1738,9 @@
case MSR_IA32_UCODE_REV:
case MSR_IA32_ARCH_CAPABILITIES:
case MSR_IA32_POWER_CTL:
+ case MSR_MTRRcap:
case MSR_IA32_CR_PAT:
+ case MSR_MTRRdefType:
case MSR_IA32_TSC_DEADLINE:
case MSR_IA32_MISC_ENABLE:
case MSR_PLATFORM_INFO:
@@ -1718,16 +1782,47 @@
int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
{
- if (tdx_has_emulated_msr(msr->index, false))
- return kvm_get_msr_common(vcpu, msr);
- return 1;
+ switch (msr->index) {
+ case MSR_MTRRcap:
+ /*
+ * Override kvm_mtrr_get_msr() which hardcodes the value.
+ * Report SMRR = 0, WC = 0, FIX = 0 VCNT = 0 to disable MTRR
+ * effectively.
+ */
+ msr->data = 0;
+ return 0;
+ default:
+ if (tdx_has_emulated_msr(msr->index, false))
+ return kvm_get_msr_common(vcpu, msr);
+ return 1;
+ }
}
int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
{
- if (tdx_has_emulated_msr(msr->index, true))
+ switch (msr->index) {
+ case MSR_MTRRdefType:
+ /*
+ * Allow writeback only for all memory.
+ * Because it's reported that fixed range MTRR isn't supported
+ * and VCNT=0, enforce MTRRDefType.FE = 0 and don't care
+ * variable range MTRRs. Only default memory type matters.
+ *
+ * bit 11 E: MTRR enable/disable
+ * bit 12 FE: Fixed-range MTRRs enable/disable
+ * (E, FE) = (1, 1): enable MTRR and Fixed range MTRR
+ * (E, FE) = (1, 0): enable MTRR, disable Fixed range MTRR
+ * (E, FE) = (0, *): disable all MTRRs. all physical memory
+ * is UC
+ */
+ if (msr->data != ((1 << 11) | MTRR_TYPE_WRBACK))
+ return 1;
return kvm_set_msr_common(vcpu, msr);
- return 1;
+ default:
+ if (tdx_has_emulated_msr(msr->index, true))
+ return kvm_set_msr_common(vcpu, msr);
+ return 1;
+ }
}
int tdx_dev_ioctl(void __user *argp)
unchanged:
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -152,6 +152,7 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
+u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
@@ -176,6 +177,7 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP
static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
+static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
--
Isaku Yamahata <[email protected]>
On Sun, 12 Mar 2023 10:55:40 -0700
[email protected] wrote:
Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
does not use it at all and all the system-scoped ioctl of SNP going through
the CCP driver. So getting system-scope information of TDX/SNP will end up
differently.
Any thought, Sean? Moving getting SNP system-wide information to
KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
> From: Sean Christopherson <[email protected]>
>
> Implement a system-scoped ioctl to get system-wide parameters for TDX.
>
> Signed-off-by: Sean Christopherson <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/include/asm/kvm-x86-ops.h | 1 +
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++
> arch/x86/kvm/vmx/main.c | 2 ++
> arch/x86/kvm/vmx/tdx.c | 51 +++++++++++++++++++++++++++
> arch/x86/kvm/vmx/x86_ops.h | 2 ++
> arch/x86/kvm/x86.c | 6 ++++
> tools/arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++
> 8 files changed, 159 insertions(+)
>
> diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> index eac4b65d1b01..b46dcac078b2 100644
> --- a/arch/x86/include/asm/kvm-x86-ops.h
> +++ b/arch/x86/include/asm/kvm-x86-ops.h
> @@ -117,6 +117,7 @@ KVM_X86_OP(enter_smm)
> KVM_X86_OP(leave_smm)
> KVM_X86_OP(enable_smi_window)
> #endif
> +KVM_X86_OP_OPTIONAL(dev_mem_enc_ioctl)
> KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
> KVM_X86_OP_OPTIONAL(mem_enc_register_region)
> KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index 00c25f6ab871..49e3ca89aced 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1719,6 +1719,7 @@ struct kvm_x86_ops {
> void (*enable_smi_window)(struct kvm_vcpu *vcpu);
> #endif
>
> + int (*dev_mem_enc_ioctl)(void __user *argp);
> int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
> int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
> int (*mem_enc_unregister_region)(struct kvm *kvm, struct kvm_enc_region *argp);
> diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
> index 6afbfbb32d56..af4c5bd0af1c 100644
> --- a/arch/x86/include/uapi/asm/kvm.h
> +++ b/arch/x86/include/uapi/asm/kvm.h
> @@ -562,4 +562,52 @@ struct kvm_pmu_event_filter {
> #define KVM_X86_DEFAULT_VM 0
> #define KVM_X86_PROTECTED_VM 1
>
> +/* Trust Domain eXtension sub-ioctl() commands. */
> +enum kvm_tdx_cmd_id {
> + KVM_TDX_CAPABILITIES = 0,
> +
> + KVM_TDX_CMD_NR_MAX,
> +};
> +
> +struct kvm_tdx_cmd {
> + /* enum kvm_tdx_cmd_id */
> + __u32 id;
> + /* flags for sub-commend. If sub-command doesn't use this, set zero. */
> + __u32 flags;
> + /*
> + * data for each sub-command. An immediate or a pointer to the actual
> + * data in process virtual address. If sub-command doesn't use it,
> + * set zero.
> + */
> + __u64 data;
> + /*
> + * Auxiliary error code. The sub-command may return TDX SEAMCALL
> + * status code in addition to -Exxx.
> + * Defined for consistency with struct kvm_sev_cmd.
> + */
> + __u64 error;
> + /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
> + __u64 unused;
> +};
> +
> +struct kvm_tdx_cpuid_config {
> + __u32 leaf;
> + __u32 sub_leaf;
> + __u32 eax;
> + __u32 ebx;
> + __u32 ecx;
> + __u32 edx;
> +};
> +
> +struct kvm_tdx_capabilities {
> + __u64 attrs_fixed0;
> + __u64 attrs_fixed1;
> + __u64 xfam_fixed0;
> + __u64 xfam_fixed1;
> +
> + __u32 nr_cpuid_configs;
> + __u32 padding;
> + struct kvm_tdx_cpuid_config cpuid_configs[0];
> +};
> +
> #endif /* _ASM_X86_KVM_H */
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index c8548004802a..6a5d0c7a2950 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -201,6 +201,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .complete_emulated_msr = kvm_complete_insn_gp,
>
> .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
> +
> + .dev_mem_enc_ioctl = tdx_dev_ioctl,
> };
>
> struct kvm_x86_init_ops vt_init_ops __initdata = {
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index e9b7aa5654e9..b59d3081d061 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -21,6 +21,57 @@ int tdx_hardware_enable(void)
> return tdx_cpu_enable();
> }
>
> +int tdx_dev_ioctl(void __user *argp)
> +{
> + struct kvm_tdx_capabilities __user *user_caps;
> + const struct tdsysinfo_struct *tdsysinfo;
> + struct kvm_tdx_capabilities caps;
> + struct kvm_tdx_cmd cmd;
> +
> + BUILD_BUG_ON(sizeof(struct kvm_tdx_cpuid_config) !=
> + sizeof(struct tdx_cpuid_config));
> +
> + if (copy_from_user(&cmd, argp, sizeof(cmd)))
> + return -EFAULT;
> + if (cmd.flags || cmd.error || cmd.unused)
> + return -EINVAL;
> + /*
> + * Currently only KVM_TDX_CAPABILITIES is defined for system-scoped
> + * mem_enc_ioctl().
> + */
> + if (cmd.id != KVM_TDX_CAPABILITIES)
> + return -EINVAL;
> +
> + tdsysinfo = tdx_get_sysinfo();
> + if (!tdsysinfo)
> + return -ENOTSUPP;
> +
> + user_caps = (void __user *)cmd.data;
> + if (copy_from_user(&caps, user_caps, sizeof(caps)))
> + return -EFAULT;
> +
> + if (caps.nr_cpuid_configs < tdsysinfo->num_cpuid_config)
> + return -E2BIG;
> +
> + caps = (struct kvm_tdx_capabilities) {
> + .attrs_fixed0 = tdsysinfo->attributes_fixed0,
> + .attrs_fixed1 = tdsysinfo->attributes_fixed1,
> + .xfam_fixed0 = tdsysinfo->xfam_fixed0,
> + .xfam_fixed1 = tdsysinfo->xfam_fixed1,
> + .nr_cpuid_configs = tdsysinfo->num_cpuid_config,
> + .padding = 0,
> + };
> +
> + if (copy_to_user(user_caps, &caps, sizeof(caps)))
> + return -EFAULT;
> + if (copy_to_user(user_caps->cpuid_configs, &tdsysinfo->cpuid_configs,
> + tdsysinfo->num_cpuid_config *
> + sizeof(struct tdx_cpuid_config)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> static int __init tdx_module_setup(void)
> {
> const struct tdsysinfo_struct *tdsysinfo;
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index b2c74c1b5bbd..78c5537e23a1 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -141,10 +141,12 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> int tdx_hardware_enable(void);
> bool tdx_is_vm_type_supported(unsigned long type);
> +int tdx_dev_ioctl(void __user *argp);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> +static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
> #endif
>
> #endif /* __KVM_X86_VMX_X86_OPS_H */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 27ab684f8374..a3dc32e33aca 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4718,6 +4718,12 @@ long kvm_arch_dev_ioctl(struct file *filp,
> r = kvm_x86_dev_has_attr(&attr);
> break;
> }
> + case KVM_MEMORY_ENCRYPT_OP:
> + r = -EINVAL;
> + if (!kvm_x86_ops.dev_mem_enc_ioctl)
> + goto out;
> + r = static_call(kvm_x86_dev_mem_enc_ioctl)(argp);
> + break;
> default:
> r = -EINVAL;
> break;
> diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
> index 6afbfbb32d56..af4c5bd0af1c 100644
> --- a/tools/arch/x86/include/uapi/asm/kvm.h
> +++ b/tools/arch/x86/include/uapi/asm/kvm.h
> @@ -562,4 +562,52 @@ struct kvm_pmu_event_filter {
> #define KVM_X86_DEFAULT_VM 0
> #define KVM_X86_PROTECTED_VM 1
>
> +/* Trust Domain eXtension sub-ioctl() commands. */
> +enum kvm_tdx_cmd_id {
> + KVM_TDX_CAPABILITIES = 0,
> +
> + KVM_TDX_CMD_NR_MAX,
> +};
> +
> +struct kvm_tdx_cmd {
> + /* enum kvm_tdx_cmd_id */
> + __u32 id;
> + /* flags for sub-commend. If sub-command doesn't use this, set zero. */
> + __u32 flags;
> + /*
> + * data for each sub-command. An immediate or a pointer to the actual
> + * data in process virtual address. If sub-command doesn't use it,
> + * set zero.
> + */
> + __u64 data;
> + /*
> + * Auxiliary error code. The sub-command may return TDX SEAMCALL
> + * status code in addition to -Exxx.
> + * Defined for consistency with struct kvm_sev_cmd.
> + */
> + __u64 error;
> + /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
> + __u64 unused;
> +};
> +
> +struct kvm_tdx_cpuid_config {
> + __u32 leaf;
> + __u32 sub_leaf;
> + __u32 eax;
> + __u32 ebx;
> + __u32 ecx;
> + __u32 edx;
> +};
> +
> +struct kvm_tdx_capabilities {
> + __u64 attrs_fixed0;
> + __u64 attrs_fixed1;
> + __u64 xfam_fixed0;
> + __u64 xfam_fixed1;
> +
> + __u32 nr_cpuid_configs;
> + __u32 padding;
> + struct kvm_tdx_cpuid_config cpuid_configs[0];
> +};
> +
> #endif /* _ASM_X86_KVM_H */
On Sun, 12 Mar 2023 10:55:41 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> Add a place holder function for TDX specific VM-scoped ioctl as mem_enc_op.
> TDX specific sub-commands will be added to retrieve/pass TDX specific
> parameters. Make mem_enc_ioctl non-optional as it's not optional now.
^ it is optional now.
>
> KVM_MEMORY_ENCRYPT_OP was introduced for VM-scoped operations specific for
> guest state-protected VM. It defined subcommands for technology-specific
> operations under KVM_MEMORY_ENCRYPT_OP. Despite its name, the subcommands
> are not limited to memory encryption, but various technology-specific
> operations are defined. It's natural to repurpose KVM_MEMORY_ENCRYPT_OP
> for TDX specific operations and define subcommands.
>
> TDX requires VM-scoped TDX-specific operations for device model, for
> example, qemu. Getting system-wide parameters, TDX-specific VM
> initialization.
^ Above two paragraphs are the "background" paragraphs, they should be in
the beginning of the patch comments.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/include/asm/kvm-x86-ops.h | 2 +-
> arch/x86/kvm/vmx/main.c | 9 +++++++++
> arch/x86/kvm/vmx/tdx.c | 26 ++++++++++++++++++++++++++
> arch/x86/kvm/vmx/x86_ops.h | 4 ++++
> arch/x86/kvm/x86.c | 4 ----
> 5 files changed, 40 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> index b46dcac078b2..58fbaa05fc8c 100644
> --- a/arch/x86/include/asm/kvm-x86-ops.h
> +++ b/arch/x86/include/asm/kvm-x86-ops.h
> @@ -117,7 +117,7 @@ KVM_X86_OP(enter_smm)
> KVM_X86_OP(leave_smm)
> KVM_X86_OP(enable_smi_window)
> #endif
> -KVM_X86_OP_OPTIONAL(dev_mem_enc_ioctl)
> +KVM_X86_OP(dev_mem_enc_ioctl)
I guess it should be KVM_X86_OP(mem_enc_ioctl) here.
> KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
> KVM_X86_OP_OPTIONAL(mem_enc_register_region)
> KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 6a5d0c7a2950..8ddd263eeabc 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -50,6 +50,14 @@ static int vt_vm_init(struct kvm *kvm)
> return vmx_vm_init(kvm);
> }
>
> +static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> +{
> + if (!is_td(kvm))
> + return -ENOTTY;
> +
> + return tdx_vm_ioctl(kvm, argp);
> +}
> +
> #define VMX_REQUIRED_APICV_INHIBITS \
> ( \
> BIT(APICV_INHIBIT_REASON_DISABLE)| \
> @@ -203,6 +211,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
>
> .dev_mem_enc_ioctl = tdx_dev_ioctl,
> + .mem_enc_ioctl = vt_mem_enc_ioctl,
> };
>
> struct kvm_x86_init_ops vt_init_ops __initdata = {
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index b59d3081d061..d759028a698e 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -72,6 +72,32 @@ int tdx_dev_ioctl(void __user *argp)
> return 0;
> }
>
> +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> +{
> + struct kvm_tdx_cmd tdx_cmd;
> + int r;
> +
> + if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd)))
> + return -EFAULT;
> + if (tdx_cmd.error || tdx_cmd.unused)
> + return -EINVAL;
> +
> + mutex_lock(&kvm->lock);
> +
> + switch (tdx_cmd.id) {
> + default:
> + r = -EINVAL;
> + goto out;
> + }
> +
> + if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd)))
> + r = -EFAULT;
> +
> +out:
> + mutex_unlock(&kvm->lock);
> + return r;
> +}
> +
> static int __init tdx_module_setup(void)
> {
> const struct tdsysinfo_struct *tdsysinfo;
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 78c5537e23a1..c70749114e9e 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -142,11 +142,15 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> int tdx_hardware_enable(void);
> bool tdx_is_vm_type_supported(unsigned long type);
> int tdx_dev_ioctl(void __user *argp);
> +
> +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
> +
> +static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
> #endif
>
> #endif /* __KVM_X86_VMX_X86_OPS_H */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index a3dc32e33aca..8687623929c3 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -6978,10 +6978,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
> goto out;
> }
> case KVM_MEMORY_ENCRYPT_OP: {
> - r = -ENOTTY;
> - if (!kvm_x86_ops.mem_enc_ioctl)
> - goto out;
> -
> r = static_call(kvm_x86_mem_enc_ioctl)(kvm, argp);
> break;
> }
On Sun, 12 Mar 2023 10:55:42 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> TDX has its own limitation on the maximum number of vcpus that the guest
> can accommodate. Allow x86 kvm backend to implement its own KVM_ENABLE_CAP
> handler and implement TDX backend for KVM_CAP_MAX_VCPUS. user space VMM,
> e.g. qemu, can specify its value instead of KVM_MAX_VCPUS.
>
I think enabling the cap here is actually "configuring the cap". KVM_CAP_MAX
_VCPUS is actually always enabled whether userspace enables it or not. It
would be nice to configure of the max VCPUS in kvm_arch_vm_ioctl() where
routines of configuring a VM should belong. E.g. KVM_SET_MAX_VCPUS.
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/include/asm/kvm-x86-ops.h | 2 ++
> arch/x86/include/asm/kvm_host.h | 2 ++
> arch/x86/kvm/vmx/main.c | 22 ++++++++++++++++++++++
> arch/x86/kvm/vmx/tdx.c | 30 ++++++++++++++++++++++++++++++
> arch/x86/kvm/vmx/tdx.h | 3 +++
> arch/x86/kvm/vmx/x86_ops.h | 2 ++
> arch/x86/kvm/x86.c | 4 ++++
> 7 files changed, 65 insertions(+)
>
> diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> index 58fbaa05fc8c..7522c193f2b4 100644
> --- a/arch/x86/include/asm/kvm-x86-ops.h
> +++ b/arch/x86/include/asm/kvm-x86-ops.h
> @@ -21,6 +21,8 @@ KVM_X86_OP(hardware_unsetup)
> KVM_X86_OP(has_emulated_msr)
> KVM_X86_OP(vcpu_after_set_cpuid)
> KVM_X86_OP(is_vm_type_supported)
> +KVM_X86_OP_OPTIONAL(max_vcpus);
> +KVM_X86_OP_OPTIONAL(vm_enable_cap)
> KVM_X86_OP(vm_init)
> KVM_X86_OP_OPTIONAL(vm_destroy)
> KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index 49e3ca89aced..d98d61e5213d 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1562,7 +1562,9 @@ struct kvm_x86_ops {
> void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
>
> bool (*is_vm_type_supported)(unsigned long vm_type);
> + int (*max_vcpus)(struct kvm *kvm);
> unsigned int vm_size;
> + int (*vm_enable_cap)(struct kvm *kvm, struct kvm_enable_cap *cap);
> int (*vm_init)(struct kvm *kvm);
> void (*vm_destroy)(struct kvm *kvm);
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 8ddd263eeabc..68bb320d0b6d 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -6,6 +6,7 @@
> #include "nested.h"
> #include "pmu.h"
> #include "tdx.h"
> +#include "tdx_arch.h"
>
> static bool enable_tdx __ro_after_init;
> module_param_named(tdx, enable_tdx, bool, 0444);
> @@ -29,6 +30,17 @@ static bool vt_is_vm_type_supported(unsigned long type)
> (enable_tdx && tdx_is_vm_type_supported(type));
> }
>
> +static int vt_max_vcpus(struct kvm *kvm)
> +{
> + if (!kvm)
> + return KVM_MAX_VCPUS;
> +
> + if (is_td(kvm))
> + return min3(kvm->max_vcpus, KVM_MAX_VCPUS, TDX_MAX_VCPUS);
> +
> + return kvm->max_vcpus;
> +}
> +
> static __init int vt_hardware_setup(void)
> {
> int ret;
> @@ -42,6 +54,14 @@ static __init int vt_hardware_setup(void)
> return 0;
> }
>
> +static int vt_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> +{
> + if (is_td(kvm))
> + return tdx_vm_enable_cap(kvm, cap);
> +
> + return -EINVAL;
> +}
> +
> static int vt_vm_init(struct kvm *kvm)
> {
> if (is_td(kvm))
> @@ -81,7 +101,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .has_emulated_msr = vmx_has_emulated_msr,
>
> .is_vm_type_supported = vt_is_vm_type_supported,
> + .max_vcpus = vt_max_vcpus,
> .vm_size = sizeof(struct kvm_vmx),
> + .vm_enable_cap = vt_vm_enable_cap,
> .vm_init = vt_vm_init,
> .vm_destroy = vmx_vm_destroy,
>
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index d759028a698e..8b02e605cfb5 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -16,6 +16,36 @@
> offsetof(struct tdsysinfo_struct, cpuid_configs)) \
> / sizeof(struct tdx_cpuid_config))
>
> +int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> +{
> + int r;
> +
> + switch (cap->cap) {
> + case KVM_CAP_MAX_VCPUS: {
> + if (cap->flags || cap->args[0] == 0)
> + return -EINVAL;
> + if (cap->args[0] > KVM_MAX_VCPUS)
> + return -E2BIG;
> + if (cap->args[0] > TDX_MAX_VCPUS)
> + return -E2BIG;
> +
> + mutex_lock(&kvm->lock);
> + if (kvm->created_vcpus)
> + r = -EBUSY;
> + else {
> + kvm->max_vcpus = cap->args[0];
> + r = 0;
> + }
> + mutex_unlock(&kvm->lock);
> + break;
> + }
> + default:
> + r = -EINVAL;
> + break;
> + }
> + return r;
> +}
> +
> int tdx_hardware_enable(void)
> {
> return tdx_cpu_enable();
> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
> index 2210c8c1e893..3860aa351bd9 100644
> --- a/arch/x86/kvm/vmx/tdx.h
> +++ b/arch/x86/kvm/vmx/tdx.h
> @@ -3,6 +3,9 @@
> #define __KVM_X86_TDX_H
>
> #ifdef CONFIG_INTEL_TDX_HOST
> +
> +#include "tdx_ops.h"
> +
> struct kvm_tdx {
> struct kvm kvm;
> /* TDX specific members follow. */
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index c70749114e9e..8118647aa8ca 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -143,6 +143,7 @@ int tdx_hardware_enable(void);
> bool tdx_is_vm_type_supported(unsigned long type);
> int tdx_dev_ioctl(void __user *argp);
>
> +int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> @@ -150,6 +151,7 @@ static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
>
> +static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
> static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
> #endif
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 8687623929c3..7b02dd40ef21 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4500,6 +4500,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> break;
> case KVM_CAP_MAX_VCPUS:
> r = KVM_MAX_VCPUS;
> + if (kvm_x86_ops.max_vcpus)
> + r = static_call(kvm_x86_max_vcpus)(kvm);
> break;
> case KVM_CAP_MAX_VCPU_ID:
> r = KVM_MAX_VCPU_IDS;
> @@ -6439,6 +6441,8 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
> break;
> default:
> r = -EINVAL;
> + if (kvm_x86_ops.vm_enable_cap)
> + r = static_call(kvm_x86_vm_enable_cap)(kvm, cap);
> break;
> }
> return r;
On Sun, 12 Mar 2023 10:55:43 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> As the first step to create TDX guest, create/destroy VM struct. Assign
> TDX private Host Key ID (HKID) to the TDX guest for memory encryption and
> allocate extra pages for the TDX guest. On destruction, free allocated
> pages, and HKID.
>
> Before tearing down private page tables, TDX requires some resources of the
> guest TD to be destroyed (i.e. HKID must have been reclaimed, etc). Add
> flush_shadow_all_private callback before tearing down private page tables
> for it.
>
> Add vm_free() of kvm_x86_ops hook at the end of kvm_arch_destroy_vm()
> because some per-VM TDX resources, e.g. TDR, need to be freed after other
> TDX resources, e.g. HKID, were freed.
>
> Co-developed-by: Kai Huang <[email protected]>
> Signed-off-by: Kai Huang <[email protected]>
> Signed-off-by: Sean Christopherson <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
>
> ---
> Changes v11 -> v12:
> - use cpu_feature_enabled().
>
> Changes v10 -> v11:
> - Fix doule free in tdx_vm_free() by setting NULL.
> - replace struct tdx_td_page tdr and tdcs from struct kvm_tdx with
> unsigned long
> ---
> arch/x86/include/asm/kvm-x86-ops.h | 2 +
> arch/x86/include/asm/kvm_host.h | 2 +
> arch/x86/kvm/vmx/main.c | 35 ++-
> arch/x86/kvm/vmx/tdx.c | 442 ++++++++++++++++++++++++++++-
> arch/x86/kvm/vmx/tdx.h | 6 +-
> arch/x86/kvm/vmx/x86_ops.h | 9 +
> arch/x86/kvm/x86.c | 8 +
> 7 files changed, 498 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> index 7522c193f2b4..c30d2d2ad686 100644
> --- a/arch/x86/include/asm/kvm-x86-ops.h
> +++ b/arch/x86/include/asm/kvm-x86-ops.h
> @@ -24,7 +24,9 @@ KVM_X86_OP(is_vm_type_supported)
> KVM_X86_OP_OPTIONAL(max_vcpus);
> KVM_X86_OP_OPTIONAL(vm_enable_cap)
> KVM_X86_OP(vm_init)
> +KVM_X86_OP_OPTIONAL(flush_shadow_all_private)
> KVM_X86_OP_OPTIONAL(vm_destroy)
> +KVM_X86_OP_OPTIONAL(vm_free)
> KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
> KVM_X86_OP(vcpu_create)
> KVM_X86_OP(vcpu_free)
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index d98d61e5213d..15f7c0d45082 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1566,7 +1566,9 @@ struct kvm_x86_ops {
> unsigned int vm_size;
> int (*vm_enable_cap)(struct kvm *kvm, struct kvm_enable_cap *cap);
> int (*vm_init)(struct kvm *kvm);
> + void (*flush_shadow_all_private)(struct kvm *kvm);
> void (*vm_destroy)(struct kvm *kvm);
> + void (*vm_free)(struct kvm *kvm);
>
> /* Create, but do not attach this VCPU */
> int (*vcpu_precreate)(struct kvm *kvm);
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 68bb320d0b6d..08ed6fc8cc3d 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -62,14 +62,41 @@ static int vt_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> return -EINVAL;
> }
>
> +static void vt_hardware_unsetup(void)
> +{
> + if (enable_tdx)
> + tdx_hardware_unsetup();
> + vmx_hardware_unsetup();
> +}
> +
> static int vt_vm_init(struct kvm *kvm)
> {
> if (is_td(kvm))
> - return -EOPNOTSUPP; /* Not ready to create guest TD yet. */
> + return tdx_vm_init(kvm);
>
> return vmx_vm_init(kvm);
> }
>
> +static void vt_flush_shadow_all_private(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + tdx_mmu_release_hkid(kvm);
> +}
> +
> +static void vt_vm_destroy(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + return;
> +
> + vmx_vm_destroy(kvm);
> +}
> +
> +static void vt_vm_free(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + tdx_vm_free(kvm);
> +}
> +
> static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> {
> if (!is_td(kvm))
> @@ -94,7 +121,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>
> .check_processor_compatibility = vmx_check_processor_compat,
>
> - .hardware_unsetup = vmx_hardware_unsetup,
> + .hardware_unsetup = vt_hardware_unsetup,
>
> .hardware_enable = vt_hardware_enable,
> .hardware_disable = vmx_hardware_disable,
> @@ -105,7 +132,9 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .vm_size = sizeof(struct kvm_vmx),
> .vm_enable_cap = vt_vm_enable_cap,
> .vm_init = vt_vm_init,
> - .vm_destroy = vmx_vm_destroy,
> + .flush_shadow_all_private = vt_flush_shadow_all_private,
> + .vm_destroy = vt_vm_destroy,
> + .vm_free = vt_vm_free,
>
> .vcpu_precreate = vmx_vcpu_precreate,
> .vcpu_create = vmx_vcpu_create,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 8b02e605cfb5..3ede8a726b47 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -5,8 +5,9 @@
>
> #include "capabilities.h"
> #include "x86_ops.h"
> -#include "x86.h"
> #include "tdx.h"
> +#include "tdx_ops.h"
> +#include "x86.h"
>
> #undef pr_fmt
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> @@ -46,11 +47,276 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> return r;
> }
>
> +struct tdx_info {
> + u8 nr_tdcs_pages;
> +};
> +
> +/* Info about the TDX module. */
> +static struct tdx_info tdx_info;
> +
> +/*
> + * Some TDX SEAMCALLs (TDH.MNG.CREATE, TDH.PHYMEM.CACHE.WB,
> + * TDH.MNG.KEY.RECLAIMID, TDH.MNG.KEY.FREEID etc) tries to acquire a global lock
> + * internally in TDX module. If failed, TDX_OPERAND_BUSY is returned without
> + * spinning or waiting due to a constraint on execution time. It's caller's
> + * responsibility to avoid race (or retry on TDX_OPERAND_BUSY). Use this mutex
> + * to avoid race in TDX module because the kernel knows better about scheduling.
> + */
> +static DEFINE_MUTEX(tdx_lock);
> +static struct mutex *tdx_mng_key_config_lock;
> +
> +static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
> +{
> + return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
> +}
> +
> +static inline bool is_td_created(struct kvm_tdx *kvm_tdx)
> +{
> + return kvm_tdx->tdr_pa;
> +}
> +
> +static inline void tdx_hkid_free(struct kvm_tdx *kvm_tdx)
> +{
> + tdx_guest_keyid_free(kvm_tdx->hkid);
> + kvm_tdx->hkid = 0;
> +}
> +
> +static inline bool is_hkid_assigned(struct kvm_tdx *kvm_tdx)
> +{
> + return kvm_tdx->hkid > 0;
> +}
> +
> int tdx_hardware_enable(void)
> {
> return tdx_cpu_enable();
> }
>
> +static void tdx_clear_page(unsigned long page_pa)
> +{
> + const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
> + void *page = __va(page_pa);
> + unsigned long i;
> +
> + if (!cpu_feature_enabled(X86_FEATURE_MOVDIR64B)) {
> + clear_page(page);
> + return;
> + }
Is it possbile to have a TDX machine without MOVDIR64B support? I am not sure
if there is any other way for the kernel to clear the posioned cache line.
If not, there should be a warn/bug at least and check if MOVDIR64B support
when initializing the TDX.
> +
> + /*
> + * Zeroing the page is only necessary for systems with MKTME-i:
> + * when re-assign one page from old keyid to a new keyid, MOVDIR64B is
> + * required to clear/write the page with new keyid to prevent integrity
> + * error when read on the page with new keyid.
> + *
> + * clflush doesn't flush cache with HKID set.
> + * The cache line could be poisoned (even without MKTME-i), clear the
> + * poison bit.
> + */
> + for (i = 0; i < PAGE_SIZE; i += 64)
> + movdir64b(page + i, zero_page);
> + /*
> + * MOVDIR64B store uses WC buffer. Prevent following memory reads
> + * from seeing potentially poisoned cache.
> + */
> + __mb();
> +}
> +
> +static int tdx_reclaim_page(hpa_t pa, bool do_wb, u16 hkid)
> +{
> + struct tdx_module_output out;
> + u64 err;
> +
> + do {
> + err = tdh_phymem_page_reclaim(pa, &out);
> + /*
> + * TDH.PHYMEM.PAGE.RECLAIM is allowed only when TD is shutdown.
> + * state. i.e. destructing TD.
> + * TDH.PHYMEM.PAGE.RECLAIM requires TDR and target page.
> + * Because we're destructing TD, it's rare to contend with TDR.
> + */
> + } while (err == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_RCX));
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_PHYMEM_PAGE_RECLAIM, err, &out);
> + return -EIO;
> + }
> +
> + if (do_wb) {
> + /*
> + * Only TDR page gets into this path. No contention is expected
> + * because of the last page of TD.
> + */
> + err = tdh_phymem_page_wbinvd(set_hkid_to_hpa(pa, hkid));
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_PHYMEM_PAGE_WBINVD, err, NULL);
> + return -EIO;
> + }
> + }
> +
> + tdx_clear_page(pa);
> + return 0;
> +}
> +
> +static void tdx_reclaim_td_page(unsigned long td_page_pa)
> +{
> + if (!td_page_pa)
> + return;
> + /*
> + * TDCX are being reclaimed. TDX module maps TDCX with HKID
> + * assigned to the TD. Here the cache associated to the TD
> + * was already flushed by TDH.PHYMEM.CACHE.WB before here, So
> + * cache doesn't need to be flushed again.
> + */
> + if (tdx_reclaim_page(td_page_pa, false, 0))
> + /*
> + * Leak the page on failure:
> + * tdx_reclaim_page() returns an error if and only if there's an
> + * unexpected, fatal error, e.g. a SEAMCALL with bad params,
> + * incorrect concurrency in KVM, a TDX Module bug, etc.
> + * Retrying at a later point is highly unlikely to be
> + * successful.
> + * No log here as tdx_reclaim_page() already did.
> + */
> + return;
> + free_page((unsigned long)__va(td_page_pa));
> +}
> +
> +static int tdx_do_tdh_phymem_cache_wb(void *param)
> +{
> + u64 err = 0;
> +
> + do {
> + err = tdh_phymem_cache_wb(!!err);
> + } while (err == TDX_INTERRUPTED_RESUMABLE);
> +
> + /* Other thread may have done for us. */
> + if (err == TDX_NO_HKID_READY_TO_WBCACHE)
> + err = TDX_SUCCESS;
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_PHYMEM_CACHE_WB, err, NULL);
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +void tdx_mmu_release_hkid(struct kvm *kvm)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + cpumask_var_t packages;
> + bool cpumask_allocated;
> + u64 err;
> + int ret;
> + int i;
> +
> + if (!is_hkid_assigned(kvm_tdx))
> + return;
> +
> + if (!is_td_created(kvm_tdx))
> + goto free_hkid;
> +
> + cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
> + cpus_read_lock();
> + for_each_online_cpu(i) {
> + if (cpumask_allocated &&
> + cpumask_test_and_set_cpu(topology_physical_package_id(i),
> + packages))
> + continue;
Is this necessary to check cpumask_allocated in the while loop? if cpumask
is not succefully allocated, wouldn't it be better to bail out just after
it?
> +
> + /*
> + * We can destroy multiple the guest TDs simultaneously.
> + * Prevent tdh_phymem_cache_wb from returning TDX_BUSY by
> + * serialization.
> + */
> + mutex_lock(&tdx_lock);
> + ret = smp_call_on_cpu(i, tdx_do_tdh_phymem_cache_wb, NULL, 1);
> + mutex_unlock(&tdx_lock);
> + if (ret)
> + break;
> + }
> + cpus_read_unlock();
> + free_cpumask_var(packages);
> +
> + mutex_lock(&tdx_lock);
> + err = tdh_mng_key_freeid(kvm_tdx->tdr_pa);
> + mutex_unlock(&tdx_lock);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_KEY_FREEID, err, NULL);
> + pr_err("tdh_mng_key_freeid failed. HKID %d is leaked.\n",
> + kvm_tdx->hkid);
> + return;
> + }
> +
> +free_hkid:
> + tdx_hkid_free(kvm_tdx);
> +}
> +
> +void tdx_vm_free(struct kvm *kvm)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + int i;
> +
> + /* Can't reclaim or free TD pages if teardown failed. */
> + if (is_hkid_assigned(kvm_tdx))
> + return;
> +
Better to explain why, as it is common to think even the teardown failed, we
should still try to reclaim the pages as many as we can.
> + if (kvm_tdx->tdcs_pa) {
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++)
> + tdx_reclaim_td_page(kvm_tdx->tdcs_pa[i]);
> + kfree(kvm_tdx->tdcs_pa);
> + kvm_tdx->tdcs_pa = NULL;
> + }
> +
> + if (!kvm_tdx->tdr_pa)
> + return;
> + /*
> + * TDX module maps TDR with TDX global HKID. TDX module may access TDR
> + * while operating on TD (Especially reclaiming TDCS). Cache flush with
> + * TDX global HKID is needed.
> + */
> + if (tdx_reclaim_page(kvm_tdx->tdr_pa, true, tdx_global_keyid))
> + return;
> +
> + free_page((unsigned long)__va(kvm_tdx->tdr_pa));
> + kvm_tdx->tdr_pa = 0;
> +}
> +
> +static int tdx_do_tdh_mng_key_config(void *param)
> +{
> + hpa_t *tdr_p = param;
> + u64 err;
> +
> + do {
> + err = tdh_mng_key_config(*tdr_p);
> +
> + /*
> + * If it failed to generate a random key, retry it because this
> + * is typically caused by an entropy error of the CPU's random
> + * number generator.
> + */
> + } while (err == TDX_KEY_GENERATION_FAILED);
> +
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_KEY_CONFIG, err, NULL);
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +static int __tdx_td_init(struct kvm *kvm);
> +
> +int tdx_vm_init(struct kvm *kvm)
> +{
> + /*
> + * TDX has its own limit of the number of vcpus in addition to
> + * KVM_MAX_VCPUS.
> + */
> + kvm->max_vcpus = min(kvm->max_vcpus, TDX_MAX_VCPUS);
> +
> + /* Place holder for TDX specific logic. */
> + return __tdx_td_init(kvm);
> +}
> +
> int tdx_dev_ioctl(void __user *argp)
> {
> struct kvm_tdx_capabilities __user *user_caps;
> @@ -102,6 +368,160 @@ int tdx_dev_ioctl(void __user *argp)
> return 0;
> }
>
> +static int __tdx_td_init(struct kvm *kvm)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + cpumask_var_t packages;
> + unsigned long *tdcs_pa = NULL;
> + unsigned long tdr_pa = 0;
> + unsigned long va;
> + int ret, i;
> + u64 err;
> +
> + ret = tdx_guest_keyid_alloc();
> + if (ret < 0)
> + return ret;
> + kvm_tdx->hkid = ret;
> +
> + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> + if (!va)
> + goto free_hkid;
> + tdr_pa = __pa(va);
> +
> + tdcs_pa = kcalloc(tdx_info.nr_tdcs_pages, sizeof(*kvm_tdx->tdcs_pa),
> + GFP_KERNEL_ACCOUNT | __GFP_ZERO);
> + if (!tdcs_pa)
> + goto free_tdr;
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> + if (!va)
> + goto free_tdcs;
> + tdcs_pa[i] = __pa(va);
> + }
> +
> + if (!zalloc_cpumask_var(&packages, GFP_KERNEL)) {
> + ret = -ENOMEM;
> + goto free_tdcs;
> + }
> + cpus_read_lock();
> + /*
> + * Need at least one CPU of the package to be online in order to
> + * program all packages for host key id. Check it.
> + */
> + for_each_present_cpu(i)
> + cpumask_set_cpu(topology_physical_package_id(i), packages);
> + for_each_online_cpu(i)
> + cpumask_clear_cpu(topology_physical_package_id(i), packages);
> + if (!cpumask_empty(packages)) {
> + ret = -EIO;
> + /*
> + * Because it's hard for human operator to figure out the
> + * reason, warn it.
> + */
> + pr_warn("All packages need to have online CPU to create TD. Online CPU and retry.\n");
> + goto free_packages;
> + }
> +
> + /*
> + * Acquire global lock to avoid TDX_OPERAND_BUSY:
> + * TDH.MNG.CREATE and other APIs try to lock the global Key Owner
> + * Table (KOT) to track the assigned TDX private HKID. It doesn't spin
> + * to acquire the lock, returns TDX_OPERAND_BUSY instead, and let the
> + * caller to handle the contention. This is because of time limitation
> + * usable inside the TDX module and OS/VMM knows better about process
> + * scheduling.
> + *
> + * APIs to acquire the lock of KOT:
> + * TDH.MNG.CREATE, TDH.MNG.KEY.FREEID, TDH.MNG.VPFLUSHDONE, and
> + * TDH.PHYMEM.CACHE.WB.
> + */
> + mutex_lock(&tdx_lock);
> + err = tdh_mng_create(tdr_pa, kvm_tdx->hkid);
> + mutex_unlock(&tdx_lock);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_CREATE, err, NULL);
> + ret = -EIO;
> + goto free_packages;
> + }
> + kvm_tdx->tdr_pa = tdr_pa;
> +
> + for_each_online_cpu(i) {
> + int pkg = topology_physical_package_id(i);
> +
> + if (cpumask_test_and_set_cpu(pkg, packages))
> + continue;
> +
> + /*
> + * Program the memory controller in the package with an
> + * encryption key associated to a TDX private host key id
> + * assigned to this TDR. Concurrent operations on same memory
> + * controller results in TDX_OPERAND_BUSY. Avoid this race by
> + * mutex.
> + */
> + mutex_lock(&tdx_mng_key_config_lock[pkg]);
> + ret = smp_call_on_cpu(i, tdx_do_tdh_mng_key_config,
> + &kvm_tdx->tdr_pa, true);
> + mutex_unlock(&tdx_mng_key_config_lock[pkg]);
> + if (ret)
> + break;
> + }
> + cpus_read_unlock();
> + free_cpumask_var(packages);
> + if (ret)
> + goto teardown;
> +
> + kvm_tdx->tdcs_pa = tdcs_pa;
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> + err = tdh_mng_addcx(kvm_tdx->tdr_pa, tdcs_pa[i]);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_ADDCX, err, NULL);
> + for (i++; i < tdx_info.nr_tdcs_pages; i++) {
> + free_page((unsigned long)__va(tdcs_pa[i]));
> + tdcs_pa[i] = 0;
> + }
> + ret = -EIO;
> + goto teardown;
> + }
> + }
> +
> + /*
> + * Note, TDH_MNG_INIT cannot be invoked here. TDH_MNG_INIT requires a dedicated
> + * ioctl() to define the configure CPUID values for the TD.
> + */
> + return 0;
> +
> + /*
> + * The sequence for freeing resources from a partially initialized TD
> + * varies based on where in the initialization flow failure occurred.
> + * Simply use the full teardown and destroy, which naturally play nice
> + * with partial initialization.
> + */
> +teardown:
> + tdx_mmu_release_hkid(kvm);
> + tdx_vm_free(kvm);
> + return ret;
> +
> +free_packages:
> + cpus_read_unlock();
> + free_cpumask_var(packages);
> +free_tdcs:
> + for (i = 0; i < tdx_info.nr_tdcs_pages; i++) {
> + if (tdcs_pa[i])
> + free_page((unsigned long)__va(tdcs_pa[i]));
> + }
> + kfree(tdcs_pa);
> + kvm_tdx->tdcs_pa = NULL;
> +
> +free_tdr:
> + if (tdr_pa)
> + free_page((unsigned long)__va(tdr_pa));
> + kvm_tdx->tdr_pa = 0;
> +free_hkid:
> + if (is_hkid_assigned(kvm_tdx))
> + tdx_hkid_free(kvm_tdx);
> + return ret;
> +}
> +
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> {
> struct kvm_tdx_cmd tdx_cmd;
> @@ -142,9 +562,11 @@ static int __init tdx_module_setup(void)
> return ret;
> }
>
> - /* Sanitary check just in case. */
> tdsysinfo = tdx_get_sysinfo();
> WARN_ON(tdsysinfo->num_cpuid_config > TDX_MAX_NR_CPUID_CONFIGS);
> + tdx_info = (struct tdx_info) {
> + .nr_tdcs_pages = tdsysinfo->tdcs_base_size / PAGE_SIZE,
> + };
>
> pr_info("TDX is supported.\n");
> return 0;
> @@ -163,6 +585,8 @@ static int __init tdx_cpu_enable_cpu(void *unused)
>
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> {
> + int max_pkgs;
> + int i;
> int r;
>
> if (!enable_ept) {
> @@ -170,6 +594,14 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> return -EINVAL;
> }
>
> + max_pkgs = topology_max_packages();
> + tdx_mng_key_config_lock = kcalloc(max_pkgs, sizeof(*tdx_mng_key_config_lock),
> + GFP_KERNEL);
> + if (!tdx_mng_key_config_lock)
> + return -ENOMEM;
> + for (i = 0; i < max_pkgs; i++)
> + mutex_init(&tdx_mng_key_config_lock[i]);
> +
> /* tdx_enable() in tdx_module_setup() requires cpus lock. */
> cpus_read_lock();
> /* TDX requires VMX. */
> @@ -193,3 +625,9 @@ int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
>
> return r;
> }
> +
> +void tdx_hardware_unsetup(void)
> +{
> + /* kfree accepts NULL. */
> + kfree(tdx_mng_key_config_lock);
> +}
> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
> index 3860aa351bd9..4b790503e43e 100644
> --- a/arch/x86/kvm/vmx/tdx.h
> +++ b/arch/x86/kvm/vmx/tdx.h
> @@ -8,7 +8,11 @@
>
> struct kvm_tdx {
> struct kvm kvm;
> - /* TDX specific members follow. */
> +
> + unsigned long tdr_pa;
> + unsigned long *tdcs_pa;
> +
> + int hkid;
> };
>
> struct vcpu_tdx {
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 8118647aa8ca..8f87eeeab97c 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -139,19 +139,28 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
>
> #ifdef CONFIG_INTEL_TDX_HOST
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> +void tdx_hardware_unsetup(void);
> int tdx_hardware_enable(void);
> bool tdx_is_vm_type_supported(unsigned long type);
> int tdx_dev_ioctl(void __user *argp);
>
> int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
> +int tdx_vm_init(struct kvm *kvm);
> +void tdx_mmu_release_hkid(struct kvm *kvm);
> +void tdx_vm_free(struct kvm *kvm);
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> +static inline void tdx_hardware_unsetup(void) {}
> static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
>
> static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
> +static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
> +static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
> +static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
> +static inline void tdx_vm_free(struct kvm *kvm) {}
> static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
> #endif
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 7b02dd40ef21..89fd8074c20c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -12398,6 +12398,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
> kvm_page_track_cleanup(kvm);
> kvm_xen_destroy_vm(kvm);
> kvm_hv_destroy_vm(kvm);
> + static_call_cond(kvm_x86_vm_free)(kvm);
> }
>
> static void memslot_rmap_free(struct kvm_memory_slot *slot)
> @@ -12710,6 +12711,13 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
>
> void kvm_arch_flush_shadow_all(struct kvm *kvm)
> {
> + /*
> + * kvm_mmu_zap_all() zaps both private and shared page tables. Before
> + * tearing down private page tables, TDX requires some TD resources to
> + * be destroyed (i.e. keyID must have been reclaimed, etc). Invoke
> + * kvm_x86_flush_shadow_all_private() for this.
> + */
> + static_call_cond(kvm_x86_flush_shadow_all_private)(kvm);
> kvm_mmu_zap_all(kvm);
> }
>
On Fri, 2023-03-24 at 18:12 -0700, Isaku Yamahata wrote:
> On Thu, Mar 16, 2023 at 10:38:02AM +0000,
> "Huang, Kai" <[email protected]> wrote:
>
> > On Sun, 2023-03-12 at 10:56 -0700, [email protected] wrote:
> > > From: Isaku Yamahata <[email protected]>
> > >
> > > Because TDX virtualize cpuid[0x1].EDX[MTRR: bit 12] to fixed 1, guest TD
> > > thinks MTRR is supported. Although TDX supports only WB for private GPA,
> > > it's desirable to support MTRR for shared GPA. As guest access to MTRR
> > > MSRs causes #VE and KVM/x86 tracks the values of MTRR MSRs, the remining
> > > part is to implement get_mt_mask method for TDX for shared GPA.
> > >
> > > Pass around shared bit from kvm fault handler to get_mt_mask method so that
> > > it can determine if the gfn is shared or private.
> > >
> >
> > I think we have an Xarray to query whether a given GFN is shared or private?
> > Can we use that?
> >
> > > Implement get_mt_mask()
> > > following vmx case for shared GPA and return WB for private GPA.
> > > the existing vmx_get_mt_mask() can't be directly used as CPU state(CR0.CD)
> > > is protected. GFN passed to kvm_mtrr_check_gfn_range_consistency() should
> > > include shared bit.
> > >
> > > Suggested-by: Kai Huang <[email protected]>
> >
> > I am not sure what is suggested by me?
> >
> > I thought what I suggested is we should have a dedicated patch to handle MTRR
> > for TDX putting all related things together.
>
> Sure. After looking at the specs, my conclusion is that guest TD can't update
> MTRR reliably. Because MTRR update requires to disable cache(CR0.CR=1), cache
> flush, and tlb flush. (SDM 3a 12.11.7: MTRR maintenance programming interface)
> Linux implements MTRR update logic according to it.
>
> While TDX enforces CR0.CD=0, trying to set CR0.CD=1 results in #GP. At the
> same time, it reports that MTRR is available via cpuid. So I come up with the
> followings.
>
> - MTRRCap(RO): report no feature available
> SMRR=0: SMRR interface unsupported
> WC=0: write combining unsupported
> FIX=0: Fixed range registers unsupported
> VCNT=0: number of variable range regitsers = 0
>
> - MTRRDefType(R/W): Only writeback even with reset state.
> E=1: enable MTRR (E=0 means all memory is UC.)
> FE=0: disable fixed range MTRRs
> type: default memory type=writeback
> Accept write this value. Other value results in #GP.
>
> - Fixed range MTRR
> #GP as fixed range MTRRs is reported as unsupported
>
> - Variable range MTRRs
> #GP as the number of variable range MTRRs is reported as zero
Looks sane to me.
>
>
> > > +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> > > +{
> > > + /* TDX private GPA is always WB. */
> > > + if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
> > > + /* MMIO is only for shared GPA. */
> > > + WARN_ON_ONCE(is_mmio);
> > > + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
> > > + }
> > > +
> > > + /* Drop shared bit as MTRR doesn't know about shared bit. */
> > > + gfn = kvm_gfn_to_private(vcpu->kvm, gfn);
> > > +
> > > + /* As TDX enforces CR0.CD to 0, pass check_cr0_cd = false. */
> > > + return __vmx_get_mt_mask(vcpu, gfn, is_mmio, false);
> > > +}
> >
> >
> > Do you know whether there's any use case of non-coherent device assignment to
> > TDX guest?
> >
> > IMHO, we should just disallow TDX guest to support non-coherent device
> > assignment, so that we can just return WB for both private and shared.
> >
> > If we support non-coherent device assignment, then if guest sets private memory
> > to non-WB memory, it believes the memory type is non-WB, but in fact TDX always
> > map private memory as WB.
> >
> > Will this be a problem, i.e. if assigned device can DMA to private memory
> > directly in the future?
>
> MTRR is legacy feature and PAT replaced it. We can rely on guest to use PAT.
> Here is the new patch for MTRR.
>
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -229,6 +229,14 @@ static void vt_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
> vmx_load_mmu_pgd(vcpu, root_hpa, pgd_level);
> }
>
> +static u8 vt_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> +{
> + if (is_td_vcpu(vcpu))
> + return tdx_get_mt_mask(vcpu, gfn, is_mmio);
> +
> + return vmx_get_mt_mask(vcpu, gfn, is_mmio);
> +}
> +
> static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> {
> if (!is_td(kvm))
> @@ -349,7 +357,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>
> .set_tss_addr = vmx_set_tss_addr,
> .set_identity_map_addr = vmx_set_identity_map_addr,
> - .get_mt_mask = vmx_get_mt_mask,
> + .get_mt_mask = vt_get_mt_mask,
>
> .get_exit_info = vmx_get_exit_info,
>
> diff -u b/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> --- b/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -347,6 +347,25 @@
> return 0;
> }
>
> +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> +{
> + /* TDX private GPA is always WB. */
> + if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
Are you still passing a "raw" GFN? Could you explain why you choose this way?
> + /* MMIO is only for shared GPA. */
> + WARN_ON_ONCE(is_mmio);
> + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
I guess it's better to include VMX_EPT_IPAT_BIT bit.
> + }
> +
> + if (is_mmio)
> + return MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT;
> +
> + if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))
> + return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;
> +
> + /* TDX enforces CR0.CD = 0 and KVM MTRR emulation enforces writeback. */
> + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
> +}
> +
On 2023-03-12 at 10:56:03 -0700, [email protected] wrote:
> From: Chao Gao <[email protected]>
>
> Current TD guest doesn't invoke MAP_GPA to convert MMIO range to shared
> before accessing it. It implies that current TD guest assumes MMIOs are
> shared.
>
> When TD tries to access assigned device's MMIO as shared, an EPT violation
Seems the patch is dealing with emulated MMIO, not assigned device's MMIO.
> is raised first. kvm_mem_is_private() checks the page shared or private
> attribute against the access type (shared bit in GPA). Then since no
> MAP_GPA is called for the MMIO, KVM thinks the MMIO is private and refuses
> shared access and doesn't set up shared EPT. Then KVM returns to TD and TD
> just retries and this causes an infinite loop.
>
> Instead of requiring guest to invoke MAP_GPA for MMIOs, assume guest MMIOs
> are shared in KVM as well and don't expect explicit calls of MAP_GAP for
> guest MMIOs (i.e., GPAs either have no kvm_memory_slot or are backed by
> host MMIOs). So, allow shared access to guest MMIOs and move the page type
> check after the corresponding pfn is available.
Didn't see the movement.
Seems the commit message needs update.
>
> Signed-off-by: Chao Gao <[email protected]>
> ---
> arch/x86/kvm/mmu/mmu.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 5883ab95ff07..ce8a896a3cfa 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -4314,7 +4314,12 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
> return RET_PF_EMULATE;
> }
>
> - if (fault->is_private != kvm_mem_is_private(vcpu->kvm, fault->gfn))
> + /*
> + * !fault->slot means MMIO. Don't require explicit GPA conversion for
> + * MMIO because MMIO is assigned at the boot time.
> + */
> + if (fault->slot &&
This only exempts emulated MMIO, how about the passthrough device's MMIO?
Thanks,
Yilun
> + fault->is_private != kvm_mem_is_private(vcpu->kvm, fault->gfn))
> return kvm_do_memory_fault_exit(vcpu, fault);
>
> if (fault->is_private)
> --
> 2.25.1
>
On Fri, Mar 24, 2023 at 10:41:56AM +0000,
"Huang, Kai" <[email protected]> wrote:
> > +static int __init tdx_module_setup(void)
> > +{
> > + int ret;
> > +
> > + ret = tdx_enable();
> > + if (ret) {
> > + pr_info("Failed to initialize TDX module.\n");
> > + return ret;
> > + }
> > +
> > + pr_info("TDX is supported.\n");
>
> Both pr_info()s are not required, because tdx_enable() internally prints them.
Ok, will drop this line.
> > #endif /* __KVM_X86_VMX_X86_OPS_H */
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 2125fcaa3973..b264012a8478 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -9435,6 +9435,16 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
> >
> > kvm_init_pmu_capability(ops->pmu_ops);
> >
> > + /*
> > + * TDX requires those methods to enable VMXON by
> > + * kvm_hardware_enable/disable_all()
> > + */
> > + static_call_update(kvm_x86_check_processor_compatibility,
> > + ops->runtime_ops->check_processor_compatibility);
> > + static_call_update(kvm_x86_hardware_enable,
> > + ops->runtime_ops->hardware_enable);
> > + static_call_update(kvm_x86_hardware_disable,
> > + ops->runtime_ops->hardware_disable);
> > r = ops->hardware_setup();
> > if (r != 0)
> > goto out_mmu_exit;
>
> Hmm.. I think this is ugly. Perhaps we should never do any
> static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> called before kvm_ops_update() and may update vendor's kvm_x86_ops.
>
> So probably use hardware_enable_all() in hardware_setup() is a bad idea.
>
> I think we have below options on how to handle:
>
> 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> something like below:
>
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> {
> ...
>
> cpus_read_lock();
> r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> if (!r)
> r = tdx_module_setup();
> on_each_cpu(vt_x86_ops.hardware_disable, ...);
> cpus_read_unlock();
>
> ...
> }
>
> But this doesn't clean up nicely when there's some particular cpus fail to do
> hardware_enable(). To clean up nicely, we do need additional things similar to
> the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> hardware_enable() successfully.
>
> 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> code self-contained. But this would require exposing kvm_x86_ops as symbol,
> which isn't nice either.
>
> 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> after kvm_ops_update().
>
> Personally, I think 3) perhaps is the most elegant one, but not sure whether
> Sean/Paolo has any opinion.
I think we can simply update the ops before calling hardware_enable() and
clean up ops on failure.
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 709134e7c12e..42c9b58fd1ef 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9436,20 +9436,15 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
kvm_init_pmu_capability(ops->pmu_ops);
/*
- * TDX requires those methods to enable VMXON by
- * kvm_hardware_enable/disable_all_nolock()
+ * Because TDX hardware_setup uses x86_ops, update ops before calling
+ * ops->hardware_setup().
*/
- static_call_update(kvm_x86_check_processor_compatibility,
- ops->runtime_ops->check_processor_compatibility);
- static_call_update(kvm_x86_hardware_enable,
- ops->runtime_ops->hardware_enable);
- static_call_update(kvm_x86_hardware_disable,
- ops->runtime_ops->hardware_disable);
+ kvm_ops_update(ops);
r = ops->hardware_setup();
- if (r != 0)
+ if (r != 0) {
+ kvm_x86_ops.hardware_enable = NULL;
goto out_mmu_exit;
-
- kvm_ops_update(ops);
+ }
for_each_online_cpu(cpu) {
smp_call_function_single(cpu, kvm_x86_check_cpu_compat, &r, 1);
--
Isaku Yamahata <[email protected]>
>
> > >
> > > + /*
> > > + * TDX requires those methods to enable VMXON by
> > > + * kvm_hardware_enable/disable_all()
> > > + */
> > > + static_call_update(kvm_x86_check_processor_compatibility,
> > > + ops->runtime_ops->check_processor_compatibility);
> > > + static_call_update(kvm_x86_hardware_enable,
> > > + ops->runtime_ops->hardware_enable);
> > > + static_call_update(kvm_x86_hardware_disable,
> > > + ops->runtime_ops->hardware_disable);
> > > r = ops->hardware_setup();
> > > if (r != 0)
> > > goto out_mmu_exit;
> >
> > Hmm.. I think this is ugly. Perhaps we should never do any
> > static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> > called before kvm_ops_update() and may update vendor's kvm_x86_ops.
> >
> > So probably use hardware_enable_all() in hardware_setup() is a bad idea.
> >
> > I think we have below options on how to handle:
> >
> > 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> > something like below:
> >
> > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > {
> > ...
> >
> > cpus_read_lock();
> > r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> > if (!r)
> > r = tdx_module_setup();
> > on_each_cpu(vt_x86_ops.hardware_disable, ...);
> > cpus_read_unlock();
> >
> > ...
> > }
> >
> > But this doesn't clean up nicely when there's some particular cpus fail to do
> > hardware_enable(). To clean up nicely, we do need additional things similar to
> > the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> > wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> > hardware_enable() successfully.
> >
> > 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> > code self-contained. But this would require exposing kvm_x86_ops as symbol,
> > which isn't nice either.
> >
> > 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> > after kvm_ops_update().
> >
> > Personally, I think 3) perhaps is the most elegant one, but not sure whether
> > Sean/Paolo has any opinion.
>
> I think we can simply update the ops before calling hardware_enable() and
> clean up ops on failure.
>
>
This doesn't work because hardware_setup() may update vendor's kvm_x86_ops.
If you do kvm_ops_update() before hardware_setup(), you need to manually update
those updated (in hardware_setup()) callbacks again after.
On Wed, Mar 29, 2023 at 01:13:45AM +0000,
"Huang, Kai" <[email protected]> wrote:
> >
> > > >
> > > > + /*
> > > > + * TDX requires those methods to enable VMXON by
> > > > + * kvm_hardware_enable/disable_all()
> > > > + */
> > > > + static_call_update(kvm_x86_check_processor_compatibility,
> > > > + ops->runtime_ops->check_processor_compatibility);
> > > > + static_call_update(kvm_x86_hardware_enable,
> > > > + ops->runtime_ops->hardware_enable);
> > > > + static_call_update(kvm_x86_hardware_disable,
> > > > + ops->runtime_ops->hardware_disable);
> > > > r = ops->hardware_setup();
> > > > if (r != 0)
> > > > goto out_mmu_exit;
> > >
> > > Hmm.. I think this is ugly. Perhaps we should never do any
> > > static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> > > called before kvm_ops_update() and may update vendor's kvm_x86_ops.
> > >
> > > So probably use hardware_enable_all() in hardware_setup() is a bad idea.
> > >
> > > I think we have below options on how to handle:
> > >
> > > 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> > > something like below:
> > >
> > > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > > {
> > > ...
> > >
> > > cpus_read_lock();
> > > r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> > > if (!r)
> > > r = tdx_module_setup();
> > > on_each_cpu(vt_x86_ops.hardware_disable, ...);
> > > cpus_read_unlock();
> > >
> > > ...
> > > }
> > >
> > > But this doesn't clean up nicely when there's some particular cpus fail to do
> > > hardware_enable(). To clean up nicely, we do need additional things similar to
> > > the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> > > wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> > > hardware_enable() successfully.
> > >
> > > 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> > > code self-contained. But this would require exposing kvm_x86_ops as symbol,
> > > which isn't nice either.
> > >
> > > 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> > > after kvm_ops_update().
> > >
> > > Personally, I think 3) perhaps is the most elegant one, but not sure whether
> > > Sean/Paolo has any opinion.
> >
> > I think we can simply update the ops before calling hardware_enable() and
> > clean up ops on failure.
> >
> >
>
> This doesn't work because hardware_setup() may update vendor's kvm_x86_ops.
>
> If you do kvm_ops_update() before hardware_setup(), you need to manually update
> those updated (in hardware_setup()) callbacks again after.
We can call kvm_ops_update() twice before and after hardware_setup().
--
Isaku Yamahata <[email protected]>
On Sat, Mar 25, 2023 at 10:43:06AM +0200,
Zhi Wang <[email protected]> wrote:
> On Sun, 12 Mar 2023 10:55:40 -0700
> [email protected] wrote:
>
> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> does not use it at all and all the system-scoped ioctl of SNP going through
> the CCP driver. So getting system-scope information of TDX/SNP will end up
> differently.
>
> Any thought, Sean? Moving getting SNP system-wide information to
> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
We only need global parameters of the TDX module, and we don't interact with TDX
module at this point. One alternative is to export those parameters via sysfs.
Also the existence of the sysfs node indicates that the TDX module is
loaded(initialized?) or not in addition to boot log. Thus we can drop system
scope one.
What do you think?
Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
I don't think it can be split out to independent driver.
Thanks,
> > From: Sean Christopherson <[email protected]>
> >
> > Implement a system-scoped ioctl to get system-wide parameters for TDX.
> >
> > Signed-off-by: Sean Christopherson <[email protected]>
> > Signed-off-by: Isaku Yamahata <[email protected]>
> > ---
> > arch/x86/include/asm/kvm-x86-ops.h | 1 +
> > arch/x86/include/asm/kvm_host.h | 1 +
> > arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++
> > arch/x86/kvm/vmx/main.c | 2 ++
> > arch/x86/kvm/vmx/tdx.c | 51 +++++++++++++++++++++++++++
> > arch/x86/kvm/vmx/x86_ops.h | 2 ++
> > arch/x86/kvm/x86.c | 6 ++++
> > tools/arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++
> > 8 files changed, 159 insertions(+)
> >
> > diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> > index eac4b65d1b01..b46dcac078b2 100644
> > --- a/arch/x86/include/asm/kvm-x86-ops.h
> > +++ b/arch/x86/include/asm/kvm-x86-ops.h
> > @@ -117,6 +117,7 @@ KVM_X86_OP(enter_smm)
> > KVM_X86_OP(leave_smm)
> > KVM_X86_OP(enable_smi_window)
> > #endif
> > +KVM_X86_OP_OPTIONAL(dev_mem_enc_ioctl)
> > KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
> > KVM_X86_OP_OPTIONAL(mem_enc_register_region)
> > KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
> > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> > index 00c25f6ab871..49e3ca89aced 100644
> > --- a/arch/x86/include/asm/kvm_host.h
> > +++ b/arch/x86/include/asm/kvm_host.h
> > @@ -1719,6 +1719,7 @@ struct kvm_x86_ops {
> > void (*enable_smi_window)(struct kvm_vcpu *vcpu);
> > #endif
> >
> > + int (*dev_mem_enc_ioctl)(void __user *argp);
> > int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
> > int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
> > int (*mem_enc_unregister_region)(struct kvm *kvm, struct kvm_enc_region *argp);
> > diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
> > index 6afbfbb32d56..af4c5bd0af1c 100644
> > --- a/arch/x86/include/uapi/asm/kvm.h
> > +++ b/arch/x86/include/uapi/asm/kvm.h
> > @@ -562,4 +562,52 @@ struct kvm_pmu_event_filter {
> > #define KVM_X86_DEFAULT_VM 0
> > #define KVM_X86_PROTECTED_VM 1
> >
> > +/* Trust Domain eXtension sub-ioctl() commands. */
> > +enum kvm_tdx_cmd_id {
> > + KVM_TDX_CAPABILITIES = 0,
> > +
> > + KVM_TDX_CMD_NR_MAX,
> > +};
> > +
> > +struct kvm_tdx_cmd {
> > + /* enum kvm_tdx_cmd_id */
> > + __u32 id;
> > + /* flags for sub-commend. If sub-command doesn't use this, set zero. */
> > + __u32 flags;
> > + /*
> > + * data for each sub-command. An immediate or a pointer to the actual
> > + * data in process virtual address. If sub-command doesn't use it,
> > + * set zero.
> > + */
> > + __u64 data;
> > + /*
> > + * Auxiliary error code. The sub-command may return TDX SEAMCALL
> > + * status code in addition to -Exxx.
> > + * Defined for consistency with struct kvm_sev_cmd.
> > + */
> > + __u64 error;
> > + /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
> > + __u64 unused;
> > +};
> > +
> > +struct kvm_tdx_cpuid_config {
> > + __u32 leaf;
> > + __u32 sub_leaf;
> > + __u32 eax;
> > + __u32 ebx;
> > + __u32 ecx;
> > + __u32 edx;
> > +};
> > +
> > +struct kvm_tdx_capabilities {
> > + __u64 attrs_fixed0;
> > + __u64 attrs_fixed1;
> > + __u64 xfam_fixed0;
> > + __u64 xfam_fixed1;
> > +
> > + __u32 nr_cpuid_configs;
> > + __u32 padding;
> > + struct kvm_tdx_cpuid_config cpuid_configs[0];
> > +};
> > +
> > #endif /* _ASM_X86_KVM_H */
> > diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> > index c8548004802a..6a5d0c7a2950 100644
> > --- a/arch/x86/kvm/vmx/main.c
> > +++ b/arch/x86/kvm/vmx/main.c
> > @@ -201,6 +201,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> > .complete_emulated_msr = kvm_complete_insn_gp,
> >
> > .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
> > +
> > + .dev_mem_enc_ioctl = tdx_dev_ioctl,
> > };
> >
> > struct kvm_x86_init_ops vt_init_ops __initdata = {
> > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > index e9b7aa5654e9..b59d3081d061 100644
> > --- a/arch/x86/kvm/vmx/tdx.c
> > +++ b/arch/x86/kvm/vmx/tdx.c
> > @@ -21,6 +21,57 @@ int tdx_hardware_enable(void)
> > return tdx_cpu_enable();
> > }
> >
> > +int tdx_dev_ioctl(void __user *argp)
> > +{
> > + struct kvm_tdx_capabilities __user *user_caps;
> > + const struct tdsysinfo_struct *tdsysinfo;
> > + struct kvm_tdx_capabilities caps;
> > + struct kvm_tdx_cmd cmd;
> > +
> > + BUILD_BUG_ON(sizeof(struct kvm_tdx_cpuid_config) !=
> > + sizeof(struct tdx_cpuid_config));
> > +
> > + if (copy_from_user(&cmd, argp, sizeof(cmd)))
> > + return -EFAULT;
> > + if (cmd.flags || cmd.error || cmd.unused)
> > + return -EINVAL;
> > + /*
> > + * Currently only KVM_TDX_CAPABILITIES is defined for system-scoped
> > + * mem_enc_ioctl().
> > + */
> > + if (cmd.id != KVM_TDX_CAPABILITIES)
> > + return -EINVAL;
> > +
> > + tdsysinfo = tdx_get_sysinfo();
> > + if (!tdsysinfo)
> > + return -ENOTSUPP;
> > +
> > + user_caps = (void __user *)cmd.data;
> > + if (copy_from_user(&caps, user_caps, sizeof(caps)))
> > + return -EFAULT;
> > +
> > + if (caps.nr_cpuid_configs < tdsysinfo->num_cpuid_config)
> > + return -E2BIG;
> > +
> > + caps = (struct kvm_tdx_capabilities) {
> > + .attrs_fixed0 = tdsysinfo->attributes_fixed0,
> > + .attrs_fixed1 = tdsysinfo->attributes_fixed1,
> > + .xfam_fixed0 = tdsysinfo->xfam_fixed0,
> > + .xfam_fixed1 = tdsysinfo->xfam_fixed1,
> > + .nr_cpuid_configs = tdsysinfo->num_cpuid_config,
> > + .padding = 0,
> > + };
> > +
> > + if (copy_to_user(user_caps, &caps, sizeof(caps)))
> > + return -EFAULT;
> > + if (copy_to_user(user_caps->cpuid_configs, &tdsysinfo->cpuid_configs,
> > + tdsysinfo->num_cpuid_config *
> > + sizeof(struct tdx_cpuid_config)))
> > + return -EFAULT;
> > +
> > + return 0;
> > +}
> > +
> > static int __init tdx_module_setup(void)
> > {
> > const struct tdsysinfo_struct *tdsysinfo;
> > diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> > index b2c74c1b5bbd..78c5537e23a1 100644
> > --- a/arch/x86/kvm/vmx/x86_ops.h
> > +++ b/arch/x86/kvm/vmx/x86_ops.h
> > @@ -141,10 +141,12 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
> > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> > int tdx_hardware_enable(void);
> > bool tdx_is_vm_type_supported(unsigned long type);
> > +int tdx_dev_ioctl(void __user *argp);
> > #else
> > static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> > static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> > static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> > +static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
> > #endif
> >
> > #endif /* __KVM_X86_VMX_X86_OPS_H */
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 27ab684f8374..a3dc32e33aca 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -4718,6 +4718,12 @@ long kvm_arch_dev_ioctl(struct file *filp,
> > r = kvm_x86_dev_has_attr(&attr);
> > break;
> > }
> > + case KVM_MEMORY_ENCRYPT_OP:
> > + r = -EINVAL;
> > + if (!kvm_x86_ops.dev_mem_enc_ioctl)
> > + goto out;
> > + r = static_call(kvm_x86_dev_mem_enc_ioctl)(argp);
> > + break;
> > default:
> > r = -EINVAL;
> > break;
> > diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
> > index 6afbfbb32d56..af4c5bd0af1c 100644
> > --- a/tools/arch/x86/include/uapi/asm/kvm.h
> > +++ b/tools/arch/x86/include/uapi/asm/kvm.h
> > @@ -562,4 +562,52 @@ struct kvm_pmu_event_filter {
> > #define KVM_X86_DEFAULT_VM 0
> > #define KVM_X86_PROTECTED_VM 1
> >
> > +/* Trust Domain eXtension sub-ioctl() commands. */
> > +enum kvm_tdx_cmd_id {
> > + KVM_TDX_CAPABILITIES = 0,
> > +
> > + KVM_TDX_CMD_NR_MAX,
> > +};
> > +
> > +struct kvm_tdx_cmd {
> > + /* enum kvm_tdx_cmd_id */
> > + __u32 id;
> > + /* flags for sub-commend. If sub-command doesn't use this, set zero. */
> > + __u32 flags;
> > + /*
> > + * data for each sub-command. An immediate or a pointer to the actual
> > + * data in process virtual address. If sub-command doesn't use it,
> > + * set zero.
> > + */
> > + __u64 data;
> > + /*
> > + * Auxiliary error code. The sub-command may return TDX SEAMCALL
> > + * status code in addition to -Exxx.
> > + * Defined for consistency with struct kvm_sev_cmd.
> > + */
> > + __u64 error;
> > + /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
> > + __u64 unused;
> > +};
> > +
> > +struct kvm_tdx_cpuid_config {
> > + __u32 leaf;
> > + __u32 sub_leaf;
> > + __u32 eax;
> > + __u32 ebx;
> > + __u32 ecx;
> > + __u32 edx;
> > +};
> > +
> > +struct kvm_tdx_capabilities {
> > + __u64 attrs_fixed0;
> > + __u64 attrs_fixed1;
> > + __u64 xfam_fixed0;
> > + __u64 xfam_fixed1;
> > +
> > + __u32 nr_cpuid_configs;
> > + __u32 padding;
> > + struct kvm_tdx_cpuid_config cpuid_configs[0];
> > +};
> > +
> > #endif /* _ASM_X86_KVM_H */
>
--
Isaku Yamahata <[email protected]>
On Wed, 2023-03-29 at 14:56 -0700, Isaku Yamahata wrote:
> On Wed, Mar 29, 2023 at 01:13:45AM +0000,
> "Huang, Kai" <[email protected]> wrote:
>
> > >
> > > > >
> > > > > + /*
> > > > > + * TDX requires those methods to enable VMXON by
> > > > > + * kvm_hardware_enable/disable_all()
> > > > > + */
> > > > > + static_call_update(kvm_x86_check_processor_compatibility,
> > > > > + ops->runtime_ops->check_processor_compatibility);
> > > > > + static_call_update(kvm_x86_hardware_enable,
> > > > > + ops->runtime_ops->hardware_enable);
> > > > > + static_call_update(kvm_x86_hardware_disable,
> > > > > + ops->runtime_ops->hardware_disable);
> > > > > r = ops->hardware_setup();
> > > > > if (r != 0)
> > > > > goto out_mmu_exit;
> > > >
> > > > Hmm.. I think this is ugly. Perhaps we should never do any
> > > > static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> > > > called before kvm_ops_update() and may update vendor's kvm_x86_ops.
> > > >
> > > > So probably use hardware_enable_all() in hardware_setup() is a bad idea.
> > > >
> > > > I think we have below options on how to handle:
> > > >
> > > > 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> > > > something like below:
> > > >
> > > > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > > > {
> > > > ...
> > > >
> > > > cpus_read_lock();
> > > > r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> > > > if (!r)
> > > > r = tdx_module_setup();
> > > > on_each_cpu(vt_x86_ops.hardware_disable, ...);
> > > > cpus_read_unlock();
> > > >
> > > > ...
> > > > }
> > > >
> > > > But this doesn't clean up nicely when there's some particular cpus fail to do
> > > > hardware_enable(). To clean up nicely, we do need additional things similar to
> > > > the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> > > > wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> > > > hardware_enable() successfully.
> > > >
> > > > 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> > > > code self-contained. But this would require exposing kvm_x86_ops as symbol,
> > > > which isn't nice either.
> > > >
> > > > 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> > > > after kvm_ops_update().
> > > >
> > > > Personally, I think 3) perhaps is the most elegant one, but not sure whether
> > > > Sean/Paolo has any opinion.
> > >
> > > I think we can simply update the ops before calling hardware_enable() and
> > > clean up ops on failure.
> > >
> > >
> >
> > This doesn't work because hardware_setup() may update vendor's kvm_x86_ops.
> >
> > If you do kvm_ops_update() before hardware_setup(), you need to manually update
> > those updated (in hardware_setup()) callbacks again after.
>
> We can call kvm_ops_update() twice before and after hardware_setup().
>
Personally I think it's too ugly.
On Sat, Mar 25, 2023 at 11:05:50AM +0200,
Zhi Wang <[email protected]> wrote:
> > diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
> > index b46dcac078b2..58fbaa05fc8c 100644
> > --- a/arch/x86/include/asm/kvm-x86-ops.h
> > +++ b/arch/x86/include/asm/kvm-x86-ops.h
> > @@ -117,7 +117,7 @@ KVM_X86_OP(enter_smm)
> > KVM_X86_OP(leave_smm)
> > KVM_X86_OP(enable_smi_window)
> > #endif
> > -KVM_X86_OP_OPTIONAL(dev_mem_enc_ioctl)
> > +KVM_X86_OP(dev_mem_enc_ioctl)
>
> I guess it should be KVM_X86_OP(mem_enc_ioctl) here.
Yes, thanks for catching it.
--
Isaku Yamahata <[email protected]>
On Sat, Mar 25, 2023 at 08:13:26PM +0200,
Zhi Wang <[email protected]> wrote:
> On Sun, 12 Mar 2023 10:55:42 -0700
> [email protected] wrote:
>
> > From: Isaku Yamahata <[email protected]>
> >
> > TDX has its own limitation on the maximum number of vcpus that the guest
> > can accommodate. Allow x86 kvm backend to implement its own KVM_ENABLE_CAP
> > handler and implement TDX backend for KVM_CAP_MAX_VCPUS. user space VMM,
> > e.g. qemu, can specify its value instead of KVM_MAX_VCPUS.
> >
>
> I think enabling the cap here is actually "configuring the cap". KVM_CAP_MAX
> _VCPUS is actually always enabled whether userspace enables it or not. It
> would be nice to configure of the max VCPUS in kvm_arch_vm_ioctl() where
> routines of configuring a VM should belong. E.g. KVM_SET_MAX_VCPUS.
I'm not sure I understand your point. Although KVM_ENABLE_CAP sounds like
only on/off feature, but it isn't. It's also used to set parameters. For
example, KVM_CAP_MAX_VCPU_ID.
KVM_SET_XXX is for run time feature. But the maxium number of vcpus is not
runtime changable. Set it at vm creation.
--
Isaku Yamahata <[email protected]>
On Tue, Mar 28, 2023 at 10:39:12AM +0800,
Xu Yilun <[email protected]> wrote:
> On 2023-03-12 at 10:56:03 -0700, [email protected] wrote:
> > From: Chao Gao <[email protected]>
> >
> > Current TD guest doesn't invoke MAP_GPA to convert MMIO range to shared
> > before accessing it. It implies that current TD guest assumes MMIOs are
> > shared.
> >
> > When TD tries to access assigned device's MMIO as shared, an EPT violation
>
> Seems the patch is dealing with emulated MMIO, not assigned device's MMIO.
That's right. Here I'm discussing about virtual device. Will drop "assigned"
word.
> > is raised first. kvm_mem_is_private() checks the page shared or private
> > attribute against the access type (shared bit in GPA). Then since no
> > MAP_GPA is called for the MMIO, KVM thinks the MMIO is private and refuses
> > shared access and doesn't set up shared EPT. Then KVM returns to TD and TD
> > just retries and this causes an infinite loop.
> >
> > Instead of requiring guest to invoke MAP_GPA for MMIOs, assume guest MMIOs
> > are shared in KVM as well and don't expect explicit calls of MAP_GAP for
> > guest MMIOs (i.e., GPAs either have no kvm_memory_slot or are backed by
> > host MMIOs). So, allow shared access to guest MMIOs and move the page type
> > check after the corresponding pfn is available.
>
> Didn't see the movement.
>
> Seems the commit message needs update.
Will update.
> > Signed-off-by: Chao Gao <[email protected]>
> > ---
> > arch/x86/kvm/mmu/mmu.c | 7 ++++++-
> > 1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> > index 5883ab95ff07..ce8a896a3cfa 100644
> > --- a/arch/x86/kvm/mmu/mmu.c
> > +++ b/arch/x86/kvm/mmu/mmu.c
> > @@ -4314,7 +4314,12 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
> > return RET_PF_EMULATE;
> > }
> >
> > - if (fault->is_private != kvm_mem_is_private(vcpu->kvm, fault->gfn))
> > + /*
> > + * !fault->slot means MMIO. Don't require explicit GPA conversion for
> > + * MMIO because MMIO is assigned at the boot time.
> > + */
> > + if (fault->slot &&
>
> This only exempts emulated MMIO, how about the passthrough device's MMIO?
This patch is for virtual MMIO. If physical device is assigned to shared
region, KVM memory slot is assigned. EPT entry is setup to point to the HPA.
--
Isaku Yamahata <[email protected]>
Hi, thanks for review.
On Sun, Mar 26, 2023 at 02:09:36PM +0300,
Zhi Wang <[email protected]> wrote:
> On Sun, 12 Mar 2023 10:55:43 -0700
> [email protected] wrote:
> > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > index 8b02e605cfb5..3ede8a726b47 100644
> > --- a/arch/x86/kvm/vmx/tdx.c
> > +++ b/arch/x86/kvm/vmx/tdx.c
> > @@ -5,8 +5,9 @@
> >
> > #include "capabilities.h"
> > #include "x86_ops.h"
> > -#include "x86.h"
> > #include "tdx.h"
> > +#include "tdx_ops.h"
> > +#include "x86.h"
> >
> > #undef pr_fmt
> > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> > @@ -46,11 +47,276 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> > return r;
> > }
> >
> > +struct tdx_info {
> > + u8 nr_tdcs_pages;
> > +};
> > +
> > +/* Info about the TDX module. */
> > +static struct tdx_info tdx_info;
> > +
> > +/*
> > + * Some TDX SEAMCALLs (TDH.MNG.CREATE, TDH.PHYMEM.CACHE.WB,
> > + * TDH.MNG.KEY.RECLAIMID, TDH.MNG.KEY.FREEID etc) tries to acquire a global lock
> > + * internally in TDX module. If failed, TDX_OPERAND_BUSY is returned without
> > + * spinning or waiting due to a constraint on execution time. It's caller's
> > + * responsibility to avoid race (or retry on TDX_OPERAND_BUSY). Use this mutex
> > + * to avoid race in TDX module because the kernel knows better about scheduling.
> > + */
> > +static DEFINE_MUTEX(tdx_lock);
> > +static struct mutex *tdx_mng_key_config_lock;
> > +
> > +static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
> > +{
> > + return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
> > +}
> > +
> > +static inline bool is_td_created(struct kvm_tdx *kvm_tdx)
> > +{
> > + return kvm_tdx->tdr_pa;
> > +}
> > +
> > +static inline void tdx_hkid_free(struct kvm_tdx *kvm_tdx)
> > +{
> > + tdx_guest_keyid_free(kvm_tdx->hkid);
> > + kvm_tdx->hkid = 0;
> > +}
> > +
> > +static inline bool is_hkid_assigned(struct kvm_tdx *kvm_tdx)
> > +{
> > + return kvm_tdx->hkid > 0;
> > +}
> > +
> > int tdx_hardware_enable(void)
> > {
> > return tdx_cpu_enable();
> > }
> >
> > +static void tdx_clear_page(unsigned long page_pa)
> > +{
> > + const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
> > + void *page = __va(page_pa);
> > + unsigned long i;
> > +
> > + if (!cpu_feature_enabled(X86_FEATURE_MOVDIR64B)) {
> > + clear_page(page);
> > + return;
> > + }
>
> Is it possbile to have a TDX machine without MOVDIR64B support? I am not sure
> if there is any other way for the kernel to clear the posioned cache line.
>
> If not, there should be a warn/bug at least and check if MOVDIR64B support
> when initializing the TDX.
Because the latest TDX specification uses movdir64b, it's safe for TDX
to assume movdir64b.
I'll add the check to TDX initialization part and drop it from here.
> > +void tdx_mmu_release_hkid(struct kvm *kvm)
> > +{
> > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > + cpumask_var_t packages;
> > + bool cpumask_allocated;
> > + u64 err;
> > + int ret;
> > + int i;
> > +
> > + if (!is_hkid_assigned(kvm_tdx))
> > + return;
> > +
> > + if (!is_td_created(kvm_tdx))
> > + goto free_hkid;
> > +
> > + cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
> > + cpus_read_lock();
> > + for_each_online_cpu(i) {
> > + if (cpumask_allocated &&
> > + cpumask_test_and_set_cpu(topology_physical_package_id(i),
> > + packages))
> > + continue;
>
> Is this necessary to check cpumask_allocated in the while loop? if cpumask
> is not succefully allocated, wouldn't it be better to bail out just after
> it?
No because we can't return error here. It's better to do in-efficiently freeing
resources instead of leak.
We can move the check out of loop. But it would be ugly
(if () {cpu loop} else {cpu loop} ) and this function isn't performance
critical. Also I think it's okay to depend on compiler optimization for loop
invariant. My compiler didn't optimize it in this case, though.
> > +
> > + /*
> > + * We can destroy multiple the guest TDs simultaneously.
> > + * Prevent tdh_phymem_cache_wb from returning TDX_BUSY by
> > + * serialization.
> > + */
> > + mutex_lock(&tdx_lock);
> > + ret = smp_call_on_cpu(i, tdx_do_tdh_phymem_cache_wb, NULL, 1);
> > + mutex_unlock(&tdx_lock);
> > + if (ret)
> > + break;
> > + }
> > + cpus_read_unlock();
> > + free_cpumask_var(packages);
> > +
> > + mutex_lock(&tdx_lock);
> > + err = tdh_mng_key_freeid(kvm_tdx->tdr_pa);
> > + mutex_unlock(&tdx_lock);
> > + if (WARN_ON_ONCE(err)) {
> > + pr_tdx_error(TDH_MNG_KEY_FREEID, err, NULL);
> > + pr_err("tdh_mng_key_freeid failed. HKID %d is leaked.\n",
> > + kvm_tdx->hkid);
> > + return;
> > + }
> > +
> > +free_hkid:
> > + tdx_hkid_free(kvm_tdx);
> > +}
> > +
> > +void tdx_vm_free(struct kvm *kvm)
> > +{
> > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > + int i;
> > +
> > + /* Can't reclaim or free TD pages if teardown failed. */
> > + if (is_hkid_assigned(kvm_tdx))
> > + return;
> > +
>
> Better to explain why, as it is common to think even the teardown failed, we
> should still try to reclaim the pages as many as we can.
Ok, here is the updated comment.
/*
* tdx_mmu_release_hkid() failed to reclaim HKID. Something went wrong
* heavily with TDX module. Give up freeing TD pages. As the function
* already warned, don't warn it again.
*/
--
Isaku Yamahata <[email protected]>
On Wed, Mar 29, 2023 at 11:17:31PM +0000,
"Huang, Kai" <[email protected]> wrote:
> On Wed, 2023-03-29 at 14:56 -0700, Isaku Yamahata wrote:
> > On Wed, Mar 29, 2023 at 01:13:45AM +0000,
> > "Huang, Kai" <[email protected]> wrote:
> >
> > > >
> > > > > >
> > > > > > + /*
> > > > > > + * TDX requires those methods to enable VMXON by
> > > > > > + * kvm_hardware_enable/disable_all()
> > > > > > + */
> > > > > > + static_call_update(kvm_x86_check_processor_compatibility,
> > > > > > + ops->runtime_ops->check_processor_compatibility);
> > > > > > + static_call_update(kvm_x86_hardware_enable,
> > > > > > + ops->runtime_ops->hardware_enable);
> > > > > > + static_call_update(kvm_x86_hardware_disable,
> > > > > > + ops->runtime_ops->hardware_disable);
> > > > > > r = ops->hardware_setup();
> > > > > > if (r != 0)
> > > > > > goto out_mmu_exit;
> > > > >
> > > > > Hmm.. I think this is ugly. Perhaps we should never do any
> > > > > static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> > > > > called before kvm_ops_update() and may update vendor's kvm_x86_ops.
> > > > >
> > > > > So probably use hardware_enable_all() in hardware_setup() is a bad idea.
> > > > >
> > > > > I think we have below options on how to handle:
> > > > >
> > > > > 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> > > > > something like below:
> > > > >
> > > > > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > > > > {
> > > > > ...
> > > > >
> > > > > cpus_read_lock();
> > > > > r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> > > > > if (!r)
> > > > > r = tdx_module_setup();
> > > > > on_each_cpu(vt_x86_ops.hardware_disable, ...);
> > > > > cpus_read_unlock();
> > > > >
> > > > > ...
> > > > > }
> > > > >
> > > > > But this doesn't clean up nicely when there's some particular cpus fail to do
> > > > > hardware_enable(). To clean up nicely, we do need additional things similar to
> > > > > the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> > > > > wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> > > > > hardware_enable() successfully.
> > > > >
> > > > > 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> > > > > code self-contained. But this would require exposing kvm_x86_ops as symbol,
> > > > > which isn't nice either.
> > > > >
> > > > > 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> > > > > after kvm_ops_update().
> > > > >
> > > > > Personally, I think 3) perhaps is the most elegant one, but not sure whether
> > > > > Sean/Paolo has any opinion.
> > > >
> > > > I think we can simply update the ops before calling hardware_enable() and
> > > > clean up ops on failure.
> > > >
> > > >
> > >
> > > This doesn't work because hardware_setup() may update vendor's kvm_x86_ops.
> > >
> > > If you do kvm_ops_update() before hardware_setup(), you need to manually update
> > > those updated (in hardware_setup()) callbacks again after.
> >
> > We can call kvm_ops_update() twice before and after hardware_setup().
> >
>
> Personally I think it's too ugly.
So you prefer the option 3 to calling kvm_ops_update() twice. Okay, I'll update
the patch.
--
Isaku Yamahata <[email protected]>
On Mon, Mar 27, 2023 at 09:54:40AM +0000,
"Huang, Kai" <[email protected]> wrote:
> > diff -u b/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > --- b/arch/x86/kvm/vmx/tdx.c
> > +++ b/arch/x86/kvm/vmx/tdx.c
> > @@ -347,6 +347,25 @@
> > return 0;
> > }
> >
> > +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> > +{
> > + /* TDX private GPA is always WB. */
> > + if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
>
> Are you still passing a "raw" GFN? Could you explain why you choose this way?
>
> > + /* MMIO is only for shared GPA. */
> > + WARN_ON_ONCE(is_mmio);
> > + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
>
> I guess it's better to include VMX_EPT_IPAT_BIT bit.
On second thought, there is no need to check it. We can simply drop this check.
u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
{
if (is_mmio)
return MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT;
if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))
return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;
/* TDX enforces CR0.CD = 0 and KVM MTRR emulation enforces writeback. */
return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
}
--
Isaku Yamahata <[email protected]>
On Wed, 2023-03-29 at 18:15 -0700, Isaku Yamahata wrote:
> On Mon, Mar 27, 2023 at 09:54:40AM +0000,
> "Huang, Kai" <[email protected]> wrote:
>
> > > diff -u b/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > > --- b/arch/x86/kvm/vmx/tdx.c
> > > +++ b/arch/x86/kvm/vmx/tdx.c
> > > @@ -347,6 +347,25 @@
> > > return 0;
> > > }
> > >
> > > +u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> > > +{
> > > + /* TDX private GPA is always WB. */
> > > + if (!(gfn & kvm_gfn_shared_mask(vcpu->kvm))) {
> >
> > Are you still passing a "raw" GFN? Could you explain why you choose this way?
> >
> > > + /* MMIO is only for shared GPA. */
> > > + WARN_ON_ONCE(is_mmio);
> > > + return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
> >
> > I guess it's better to include VMX_EPT_IPAT_BIT bit.
>
> On second thought, there is no need to check it. We can simply drop this check.
>
> u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)
> {
> if (is_mmio)
> return MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT;
>
> if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))
> return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;
>
> /* TDX enforces CR0.CD = 0 and KVM MTRR emulation enforces writeback. */
> return MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT;
> }
>
>
I think for private page, _theoretically_, you should include VMX_EPT_IPAT_BIT
(because the TDX module spec says the "access semantics for private is WB", but
not "private is _mapped_ as WB"). But in practice this doesn't matter because
the mirrored-EPT is never used by hardware.
While for shared page, when guest has non-coherent DMA, IIUC your intention is
you still want to horner guest's PAT, so you omitted the VMX_EPT_IPAT_BIT.
On Wed, Mar 29, 2023 at 04:17:22PM -0700,
Isaku Yamahata <[email protected]> wrote:
> On Sat, Mar 25, 2023 at 10:43:06AM +0200,
> Zhi Wang <[email protected]> wrote:
>
> > On Sun, 12 Mar 2023 10:55:40 -0700
> > [email protected] wrote:
> >
> > Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> > does not use it at all and all the system-scoped ioctl of SNP going through
> > the CCP driver. So getting system-scope information of TDX/SNP will end up
> > differently.
> >
> > Any thought, Sean? Moving getting SNP system-wide information to
> > KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> > CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
>
> We only need global parameters of the TDX module, and we don't interact with TDX
> module at this point. One alternative is to export those parameters via sysfs.
> Also the existence of the sysfs node indicates that the TDX module is
> loaded(initialized?) or not in addition to boot log. Thus we can drop system
> scope one.
> What do you think?
>
> Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
> KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
> I don't think it can be split out to independent driver.
Here is the patch to export those info via sysfs.
From e0744e506eb92e47d8317e489945a3ba804edfa7 Mon Sep 17 00:00:00 2001
Message-Id: <e0744e506eb92e47d8317e489945a3ba804edfa7.1680221730.git.isaku.yamahata@intel.com>
In-Reply-To: <8e0bc0e8e5d435f54f10c7642a862629ef2acb89.1680221729.git.isaku.yamahata@intel.com>
References: <8e0bc0e8e5d435f54f10c7642a862629ef2acb89.1680221729.git.isaku.yamahata@intel.com>
From: Isaku Yamahata <[email protected]>
Date: Thu, 30 Mar 2023 00:05:03 -0700
Subject: [PATCH] x86/virt/tdx: Export TD config params of TDX module via sysfs
TDX module has parameters for VMM to configure TD. User space VMM, e.g.
qemu, needs to know it. Export them to user space via sysfs.
TDX 1.0 provides TDH.SYS.INFO to provide system information in
TDSYSINFO_STRUCT. Its future extensibility is limited because of its
struct. From TDX 1.5, TDH.SYS.RD(metadata field_id) to read the info
specified by field id. So instead of exporting TDSYSINFO_STRUCT, adapt
metadata way to export those system information.
Signed-off-by: Isaku Yamahata <[email protected]>
---
Documentation/ABI/testing/sysfs-firmware-tdx | 23 +++
arch/x86/include/asm/tdx.h | 33 ++++
arch/x86/virt/vmx/tdx/tdx.c | 164 +++++++++++++++++++
arch/x86/virt/vmx/tdx/tdx.h | 18 ++
4 files changed, 238 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-firmware-tdx
diff --git a/Documentation/ABI/testing/sysfs-firmware-tdx b/Documentation/ABI/testing/sysfs-firmware-tdx
new file mode 100644
index 000000000000..1f26fb178144
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-tdx
@@ -0,0 +1,23 @@
+What: /sys/firmware/tdx/tdx_module/metadata
+Date: March 2023
+KernelVersion: 6.3
+Contact: Isaku Yamahata <[email protected]>, [email protected]
+Users: qemu, libvirt
+Description:
+ The TDX feature requires a firmware that is known as the TDX
+ module. The TDX module exposes its metadata in the following
+ read-only files. The information corresponds to the TDX global
+ metadata specified by 64bit field id. The file name is hex
+ string in lower case. The value is binary.
+ User space VMM like qemu needs refer to them to determine what
+ parameters are needed or allowed to configure guest TDs.
+
+ ================== ============================================
+ 1900000300000000 ATTRIBUTES_FIXED0
+ 1900000300000001 ATTRIBUTES_FIXED1
+ 1900000300000002 XFAM_FIXED0
+ 1900000300000003 XFAM_FIXED1
+ 9900000100000004 NUM_CPUID_CONFIG
+ 9900000300000400 CPUID_LEAVES
+ 9900000300000500 CPUID_VALUES
+ ================== ============================================
\ No newline at end of file
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 05870e5ed131..c650ac22a916 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -110,6 +110,39 @@ struct tdx_cpuid_config {
u32 edx;
} __packed;
+struct tdx_cpuid_config_leaf {
+ u32 leaf;
+ u32 sub_leaf;
+} __packed;
+static_assert(offsetof(struct tdx_cpuid_config, leaf) ==
+ offsetof(struct tdx_cpuid_config_leaf, leaf));
+static_assert(offsetof(struct tdx_cpuid_config, sub_leaf) ==
+ offsetof(struct tdx_cpuid_config_leaf, sub_leaf));
+static_assert(offsetofend(struct tdx_cpuid_config, sub_leaf) ==
+ sizeof(struct tdx_cpuid_config_leaf));
+
+struct tdx_cpuid_config_value {
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+ u32 edx;
+} __packed;
+static_assert(offsetof(struct tdx_cpuid_config, eax) -
+ offsetof(struct tdx_cpuid_config, eax) ==
+ offsetof(struct tdx_cpuid_config_value, eax));
+static_assert(offsetof(struct tdx_cpuid_config, ebx) -
+ offsetof(struct tdx_cpuid_config, eax) ==
+ offsetof(struct tdx_cpuid_config_value, ebx));
+static_assert(offsetof(struct tdx_cpuid_config, ecx) -
+ offsetof(struct tdx_cpuid_config, eax) ==
+ offsetof(struct tdx_cpuid_config_value, ecx));
+static_assert(offsetof(struct tdx_cpuid_config, edx) -
+ offsetof(struct tdx_cpuid_config, eax) ==
+ offsetof(struct tdx_cpuid_config_value, edx));
+static_assert(offsetofend(struct tdx_cpuid_config, edx) -
+ offsetof(struct tdx_cpuid_config, eax) ==
+ sizeof(struct tdx_cpuid_config_value));
+
#define TDSYSINFO_STRUCT_SIZE 1024
#define TDSYSINFO_STRUCT_ALIGNMENT 1024
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index f9f9c1b76501..56ca520d67d6 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -33,6 +33,12 @@
#include <asm/tdx.h>
#include "tdx.h"
+#ifdef CONFIG_SYSFS
+static int tdx_sysfs_init(void);
+#else
+static inline int tdx_sysfs_init(void) { return 0;}
+#endif
+
u32 tdx_global_keyid __ro_after_init;
EXPORT_SYMBOL_GPL(tdx_global_keyid);
static u32 tdx_guest_keyid_start __ro_after_init;
@@ -399,6 +405,10 @@ static int __tdx_get_sysinfo(struct tdsysinfo_struct *sysinfo,
if (ret)
return ret;
+ ret = tdx_sysfs_init();
+ if (ret)
+ return ret;
+
pr_info("TDX module: atributes 0x%x, vendor_id 0x%x, major_version %u, minor_version %u, build_date %u, build_num %u",
sysinfo->attributes, sysinfo->vendor_id,
sysinfo->major_version, sysinfo->minor_version,
@@ -1367,3 +1377,157 @@ int tdx_enable(void)
return ret;
}
EXPORT_SYMBOL_GPL(tdx_enable);
+
+#ifdef CONFIG_SYSFS
+
+static struct kobject *tdx_kobj;
+static struct kobject *tdx_module_kobj;
+static struct kobject *tdx_metadata_kobj;
+
+#define TDX_METADATA_ATTR(_name, field_id_name, _size) \
+static struct bin_attribute tdx_metadata_ ## _name = { \
+ .attr = { \
+ .name = field_id_name, \
+ .mode = 0444, \
+ }, \
+ .size = _size, \
+ .read = tdx_metadata_ ## _name ## _show, \
+}
+
+#define TDX_METADATA_ATTR_SHOW(_name, field_id_name) \
+static ssize_t tdx_metadata_ ## _name ## _show(struct file *filp, struct kobject *kobj, \
+ struct bin_attribute *bin_attr, \
+ char *buf, loff_t offset, size_t count) \
+{ \
+ struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo); \
+ \
+ return memory_read_from_buffer(buf, count, &offset, \
+ &sysinfo->_name, \
+ sizeof(sysinfo->_name)); \
+} \
+TDX_METADATA_ATTR(_name, field_id_name, sizeof_field(struct tdsysinfo_struct, _name))
+
+TDX_METADATA_ATTR_SHOW(attributes_fixed0, TDX_METADATA_ATTRIBUTES_FIXED0_NAME);
+TDX_METADATA_ATTR_SHOW(attributes_fixed1, TDX_METADATA_ATTRIBUTES_FIXED1_NAME);
+TDX_METADATA_ATTR_SHOW(xfam_fixed0, TDX_METADATA_XFAM_FIXED0_NAME);
+TDX_METADATA_ATTR_SHOW(xfam_fixed1, TDX_METADATA_XFAM_FIXED1_NAME);
+
+static ssize_t tdx_metadata_num_cpuid_config_show(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t offset, size_t count)
+{
+ struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
+ /*
+ * Although tdsysinfo_struct.num_cpuid_config is defined as u32 for
+ * alignment, TDX 1.5 defines metadata NUM_CONFIG_CPUID as u16.
+ */
+ u16 tmp = (u16)sysinfo->num_cpuid_config;
+
+ WARN_ON_ONCE(tmp != sysinfo->num_cpuid_config);
+ return memory_read_from_buffer(buf, count, &offset, &tmp, sizeof(tmp));
+}
+TDX_METADATA_ATTR(num_cpuid_config, TDX_METADATA_NUM_CPUID_CONFIG_NAME, sizeof(u16));
+
+static ssize_t tdx_metadata_cpuid_leaves_show(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t offset, size_t count)
+{
+ struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
+ ssize_t r;
+ struct tdx_cpuid_config_leaf *tmp;
+ u32 i;
+
+ tmp = kmalloc(bin_attr->size, GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ for (i = 0; i < sysinfo->num_cpuid_config; i++) {
+ struct tdx_cpuid_config *c = &sysinfo->cpuid_configs[i];
+ struct tdx_cpuid_config_leaf *leaf = (struct tdx_cpuid_config_leaf *)c;
+
+ memcpy(tmp + i, leaf, sizeof(*leaf));
+ }
+
+ r = memory_read_from_buffer(buf, count, &offset, tmp, bin_attr->size);
+ kfree(tmp);
+ return r;
+}
+
+TDX_METADATA_ATTR(cpuid_leaves, TDX_METADATA_CPUID_LEAVES_NAME, 0);
+
+static ssize_t tdx_metadata_cpuid_values_show(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t offset, size_t count)
+{
+ struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
+ struct tdx_cpuid_config_value *tmp;
+ ssize_t r;
+ u32 i;
+
+ tmp = kmalloc(bin_attr->size, GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ for (i = 0; i < sysinfo->num_cpuid_config; i++) {
+ struct tdx_cpuid_config *c = &sysinfo->cpuid_configs[i];
+ struct tdx_cpuid_config_value *value = (struct tdx_cpuid_config_value *)&c->eax;
+
+ memcpy(tmp + i, value, sizeof(*value));
+ }
+
+ r = memory_read_from_buffer(buf, count, &offset, tmp, bin_attr->size);
+ kfree(tmp);
+ return r;
+}
+
+TDX_METADATA_ATTR(cpuid_values, TDX_METADATA_CPUID_VALUES_NAME, 0);
+
+static struct bin_attribute *tdx_metadata_attrs[] = {
+ &tdx_metadata_attributes_fixed0,
+ &tdx_metadata_attributes_fixed1,
+ &tdx_metadata_xfam_fixed0,
+ &tdx_metadata_xfam_fixed1,
+ &tdx_metadata_num_cpuid_config,
+ &tdx_metadata_cpuid_leaves,
+ &tdx_metadata_cpuid_values,
+ NULL,
+};
+
+static const struct attribute_group tdx_metadata_attr_group = {
+ .bin_attrs = tdx_metadata_attrs,
+};
+
+static int tdx_sysfs_init(void)
+{
+ struct tdsysinfo_struct *sysinfo;
+ int ret;
+
+ tdx_kobj = kobject_create_and_add("tdx", firmware_kobj);
+ if (!tdx_kobj) {
+ pr_err("kobject_create_and_add tdx failed\n");
+ return -EINVAL;
+ }
+
+ tdx_module_kobj = kobject_create_and_add("tdx_module", tdx_kobj);
+ if (!tdx_module_kobj) {
+ pr_err("kobject_create_and_add tdx_module failed\n");
+ return -EINVAL;
+ }
+ tdx_metadata_kobj = kobject_create_and_add("metadata", tdx_module_kobj);
+ if (!tdx_metadata_kobj) {
+ pr_err("Sysfs exporting tdx global metadata failed %d\n", ret);
+ return -EINVAL;
+ }
+
+ sysinfo = &PADDED_STRUCT(tdsysinfo);
+ tdx_metadata_cpuid_leaves.size = sysinfo->num_cpuid_config *
+ sizeof(struct tdx_cpuid_config_leaf);
+ tdx_metadata_cpuid_values.size = sysinfo->num_cpuid_config *
+ sizeof(struct tdx_cpuid_config_value);
+ ret = sysfs_create_group(tdx_metadata_kobj, &tdx_metadata_attr_group);
+ if (ret)
+ pr_err("Sysfs exporting tdx module attributes failed %d\n", ret);
+
+ return ret;
+}
+#endif
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index db0cbcceb5b3..a48f38fe6cc4 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -93,4 +93,22 @@ struct tdmr_info_list {
int max_tdmrs; /* How many 'tdmr_info's are allocated */
};
+/* TDX metadata base field id. */
+#define TDX_METADATA_ATTRIBUTES_FIXED0 0x1900000300000000ULL
+#define TDX_METADATA_ATTRIBUTES_FIXED1 0x1900000300000001ULL
+#define TDX_METADATA_XFAM_FIXED0 0x1900000300000002ULL
+#define TDX_METADATA_XFAM_FIXED1 0x1900000300000003ULL
+#define TDX_METADATA_NUM_CPUID_CONFIG 0x9900000100000004ULL
+#define TDX_METADATA_CPUID_LEAVES 0x9900000300000400ULL
+#define TDX_METADATA_CPUID_VALUES 0x9900000300000500ULL
+
+/* File name for sysfs: hex with lower case. */
+#define TDX_METADATA_ATTRIBUTES_FIXED0_NAME "1900000300000000"
+#define TDX_METADATA_ATTRIBUTES_FIXED1_NAME "1900000300000001"
+#define TDX_METADATA_XFAM_FIXED0_NAME "1900000300000002"
+#define TDX_METADATA_XFAM_FIXED1_NAME "1900000300000003"
+#define TDX_METADATA_NUM_CPUID_CONFIG_NAME "9900000100000004"
+#define TDX_METADATA_CPUID_LEAVES_NAME "9900000300000400"
+#define TDX_METADATA_CPUID_VALUES_NAME "9900000300000500"
+
#endif
--
2.25.1
--
Isaku Yamahata <[email protected]>
On 3/25/2023 4:43 PM, Zhi Wang wrote:
> On Sun, 12 Mar 2023 10:55:40 -0700
> [email protected] wrote:
>
> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> does not use it at all and all the system-scoped ioctl of SNP going through
> the CCP driver. So getting system-scope information of TDX/SNP will end up
> differently.
>
> Any thought, Sean? Moving getting SNP system-wide information to
> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
What's the real different of it? For me, it's just renaming
KVM_MEMORY_ENCRYPT_OP to KVM_TDX_DEV_OP and maybe add some error message
if the IOCTL is issued for AMD plaform.
On Fri, 31 Mar 2023 14:59:18 +0800
Xiaoyao Li <[email protected]> wrote:
> On 3/25/2023 4:43 PM, Zhi Wang wrote:
> > On Sun, 12 Mar 2023 10:55:40 -0700
> > [email protected] wrote:
> >
> > Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> > does not use it at all and all the system-scoped ioctl of SNP going through
> > the CCP driver. So getting system-scope information of TDX/SNP will end up
> > differently.
> >
> > Any thought, Sean? Moving getting SNP system-wide information to
> > KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> > CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
>
> What's the real different of it? For me, it's just renaming
> KVM_MEMORY_ENCRYPT_OP to KVM_TDX_DEV_OP and maybe add some error message
> if the IOCTL is issued for AMD plaform.
>
Hi:
The ioctl is the API for the userspace. The purpose is to be orthogonal,
avoid confusion and reflect its nature. A "generic" name with only one
implementation is fine in the early design. But if the other implementation
at the same level is pretty sure not going to use it, then the abstraction,
which is only abstracted for one implementation, is just confusing.
The possible strategies are:
1) Re-factor the other implementation to fit the current abstraction.
2) Give up the abstraction. Go "specific".
For 1), it seems not realistic due to the efforts of re-factoring the SEV
driver.
For 2), there can be several ways: a. renaming it, let the name reflect
its nature. IMO, KVM_TDX_DEV_OP is not ideal as well, but I don't have a
better one. b. moving it to a proper layer of the implementation. But
it is also not realistic to have a "TDX" driver because of it. That's why
I am torn here.
On Thu, 30 Mar 2023 17:18:03 -0700
Isaku Yamahata <[email protected]> wrote:
> On Wed, Mar 29, 2023 at 04:17:22PM -0700,
> Isaku Yamahata <[email protected]> wrote:
>
> > On Sat, Mar 25, 2023 at 10:43:06AM +0200,
> > Zhi Wang <[email protected]> wrote:
> >
> > > On Sun, 12 Mar 2023 10:55:40 -0700
> > > [email protected] wrote:
> > >
> > > Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> > > does not use it at all and all the system-scoped ioctl of SNP going through
> > > the CCP driver. So getting system-scope information of TDX/SNP will end up
> > > differently.
> > >
> > > Any thought, Sean? Moving getting SNP system-wide information to
> > > KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> > > CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
> >
> > We only need global parameters of the TDX module, and we don't interact with TDX
> > module at this point. One alternative is to export those parameters via sysfs.
> > Also the existence of the sysfs node indicates that the TDX module is
> > loaded(initialized?) or not in addition to boot log. Thus we can drop system
> > scope one.
> > What do you think?
> >
I like this idea and the patch below, it feels right for me now. It would be nice
if more folks can chime in and comment.
> > Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
> > KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
> > I don't think it can be split out to independent driver.
>
They can stay in KVM as they are KVM-specific. SNP also has KVM-specific ioctls
which wraps the SEV driver calls. At this level, both TDX and SNP go their specific
implementation without more abstraction other than KVM_ENCRYPT_MEMORY_OP. Their
strategies are aligned.
The problem of the previous approach was the abstraction that no other implementation
is using it. It is like, TDX wants a higher abstraction to cover both TDX and SNP,
but SNP is not using it, which makes the abstraction looks strange.
> Here is the patch to export those info via sysfs.
>
> From e0744e506eb92e47d8317e489945a3ba804edfa7 Mon Sep 17 00:00:00 2001
> Message-Id: <e0744e506eb92e47d8317e489945a3ba804edfa7.1680221730.git.isaku.yamahata@intel.com>
> In-Reply-To: <8e0bc0e8e5d435f54f10c7642a862629ef2acb89.1680221729.git.isaku.yamahata@intel.com>
> References: <8e0bc0e8e5d435f54f10c7642a862629ef2acb89.1680221729.git.isaku.yamahata@intel.com>
> From: Isaku Yamahata <[email protected]>
> Date: Thu, 30 Mar 2023 00:05:03 -0700
> Subject: [PATCH] x86/virt/tdx: Export TD config params of TDX module via sysfs
>
> TDX module has parameters for VMM to configure TD. User space VMM, e.g.
> qemu, needs to know it. Export them to user space via sysfs.
>
> TDX 1.0 provides TDH.SYS.INFO to provide system information in
> TDSYSINFO_STRUCT. Its future extensibility is limited because of its
> struct. From TDX 1.5, TDH.SYS.RD(metadata field_id) to read the info
> specified by field id. So instead of exporting TDSYSINFO_STRUCT, adapt
> metadata way to export those system information.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> Documentation/ABI/testing/sysfs-firmware-tdx | 23 +++
> arch/x86/include/asm/tdx.h | 33 ++++
> arch/x86/virt/vmx/tdx/tdx.c | 164 +++++++++++++++++++
> arch/x86/virt/vmx/tdx/tdx.h | 18 ++
> 4 files changed, 238 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-firmware-tdx
>
> diff --git a/Documentation/ABI/testing/sysfs-firmware-tdx b/Documentation/ABI/testing/sysfs-firmware-tdx
> new file mode 100644
> index 000000000000..1f26fb178144
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-firmware-tdx
> @@ -0,0 +1,23 @@
> +What: /sys/firmware/tdx/tdx_module/metadata
> +Date: March 2023
> +KernelVersion: 6.3
> +Contact: Isaku Yamahata <[email protected]>, [email protected]
> +Users: qemu, libvirt
> +Description:
> + The TDX feature requires a firmware that is known as the TDX
> + module. The TDX module exposes its metadata in the following
> + read-only files. The information corresponds to the TDX global
> + metadata specified by 64bit field id. The file name is hex
> + string in lower case. The value is binary.
> + User space VMM like qemu needs refer to them to determine what
> + parameters are needed or allowed to configure guest TDs.
> +
> + ================== ============================================
> + 1900000300000000 ATTRIBUTES_FIXED0
> + 1900000300000001 ATTRIBUTES_FIXED1
> + 1900000300000002 XFAM_FIXED0
> + 1900000300000003 XFAM_FIXED1
> + 9900000100000004 NUM_CPUID_CONFIG
> + 9900000300000400 CPUID_LEAVES
> + 9900000300000500 CPUID_VALUES
> + ================== ============================================
> \ No newline at end of file
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index 05870e5ed131..c650ac22a916 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -110,6 +110,39 @@ struct tdx_cpuid_config {
> u32 edx;
> } __packed;
>
> +struct tdx_cpuid_config_leaf {
> + u32 leaf;
> + u32 sub_leaf;
> +} __packed;
> +static_assert(offsetof(struct tdx_cpuid_config, leaf) ==
> + offsetof(struct tdx_cpuid_config_leaf, leaf));
> +static_assert(offsetof(struct tdx_cpuid_config, sub_leaf) ==
> + offsetof(struct tdx_cpuid_config_leaf, sub_leaf));
> +static_assert(offsetofend(struct tdx_cpuid_config, sub_leaf) ==
> + sizeof(struct tdx_cpuid_config_leaf));
> +
> +struct tdx_cpuid_config_value {
> + u32 eax;
> + u32 ebx;
> + u32 ecx;
> + u32 edx;
> +} __packed;
> +static_assert(offsetof(struct tdx_cpuid_config, eax) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, eax));
> +static_assert(offsetof(struct tdx_cpuid_config, ebx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, ebx));
> +static_assert(offsetof(struct tdx_cpuid_config, ecx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, ecx));
> +static_assert(offsetof(struct tdx_cpuid_config, edx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, edx));
> +static_assert(offsetofend(struct tdx_cpuid_config, edx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + sizeof(struct tdx_cpuid_config_value));
> +
> #define TDSYSINFO_STRUCT_SIZE 1024
> #define TDSYSINFO_STRUCT_ALIGNMENT 1024
>
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index f9f9c1b76501..56ca520d67d6 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -33,6 +33,12 @@
> #include <asm/tdx.h>
> #include "tdx.h"
>
> +#ifdef CONFIG_SYSFS
> +static int tdx_sysfs_init(void);
> +#else
> +static inline int tdx_sysfs_init(void) { return 0;}
> +#endif
> +
> u32 tdx_global_keyid __ro_after_init;
> EXPORT_SYMBOL_GPL(tdx_global_keyid);
> static u32 tdx_guest_keyid_start __ro_after_init;
> @@ -399,6 +405,10 @@ static int __tdx_get_sysinfo(struct tdsysinfo_struct *sysinfo,
> if (ret)
> return ret;
>
> + ret = tdx_sysfs_init();
> + if (ret)
> + return ret;
> +
> pr_info("TDX module: atributes 0x%x, vendor_id 0x%x, major_version %u, minor_version %u, build_date %u, build_num %u",
> sysinfo->attributes, sysinfo->vendor_id,
> sysinfo->major_version, sysinfo->minor_version,
> @@ -1367,3 +1377,157 @@ int tdx_enable(void)
> return ret;
> }
> EXPORT_SYMBOL_GPL(tdx_enable);
> +
> +#ifdef CONFIG_SYSFS
> +
> +static struct kobject *tdx_kobj;
> +static struct kobject *tdx_module_kobj;
> +static struct kobject *tdx_metadata_kobj;
> +
> +#define TDX_METADATA_ATTR(_name, field_id_name, _size) \
> +static struct bin_attribute tdx_metadata_ ## _name = { \
> + .attr = { \
> + .name = field_id_name, \
> + .mode = 0444, \
> + }, \
> + .size = _size, \
> + .read = tdx_metadata_ ## _name ## _show, \
> +}
> +
> +#define TDX_METADATA_ATTR_SHOW(_name, field_id_name) \
> +static ssize_t tdx_metadata_ ## _name ## _show(struct file *filp, struct kobject *kobj, \
> + struct bin_attribute *bin_attr, \
> + char *buf, loff_t offset, size_t count) \
> +{ \
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo); \
> + \
> + return memory_read_from_buffer(buf, count, &offset, \
> + &sysinfo->_name, \
> + sizeof(sysinfo->_name)); \
> +} \
> +TDX_METADATA_ATTR(_name, field_id_name, sizeof_field(struct tdsysinfo_struct, _name))
> +
> +TDX_METADATA_ATTR_SHOW(attributes_fixed0, TDX_METADATA_ATTRIBUTES_FIXED0_NAME);
> +TDX_METADATA_ATTR_SHOW(attributes_fixed1, TDX_METADATA_ATTRIBUTES_FIXED1_NAME);
> +TDX_METADATA_ATTR_SHOW(xfam_fixed0, TDX_METADATA_XFAM_FIXED0_NAME);
> +TDX_METADATA_ATTR_SHOW(xfam_fixed1, TDX_METADATA_XFAM_FIXED1_NAME);
> +
> +static ssize_t tdx_metadata_num_cpuid_config_show(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr,
> + char *buf, loff_t offset, size_t count)
> +{
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
> + /*
> + * Although tdsysinfo_struct.num_cpuid_config is defined as u32 for
> + * alignment, TDX 1.5 defines metadata NUM_CONFIG_CPUID as u16.
> + */
> + u16 tmp = (u16)sysinfo->num_cpuid_config;
> +
> + WARN_ON_ONCE(tmp != sysinfo->num_cpuid_config);
> + return memory_read_from_buffer(buf, count, &offset, &tmp, sizeof(tmp));
> +}
> +TDX_METADATA_ATTR(num_cpuid_config, TDX_METADATA_NUM_CPUID_CONFIG_NAME, sizeof(u16));
> +
> +static ssize_t tdx_metadata_cpuid_leaves_show(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr, char *buf,
> + loff_t offset, size_t count)
> +{
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
> + ssize_t r;
> + struct tdx_cpuid_config_leaf *tmp;
> + u32 i;
> +
> + tmp = kmalloc(bin_attr->size, GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
> +
> + for (i = 0; i < sysinfo->num_cpuid_config; i++) {
> + struct tdx_cpuid_config *c = &sysinfo->cpuid_configs[i];
> + struct tdx_cpuid_config_leaf *leaf = (struct tdx_cpuid_config_leaf *)c;
> +
> + memcpy(tmp + i, leaf, sizeof(*leaf));
> + }
> +
> + r = memory_read_from_buffer(buf, count, &offset, tmp, bin_attr->size);
> + kfree(tmp);
> + return r;
> +}
> +
> +TDX_METADATA_ATTR(cpuid_leaves, TDX_METADATA_CPUID_LEAVES_NAME, 0);
> +
> +static ssize_t tdx_metadata_cpuid_values_show(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr, char *buf,
> + loff_t offset, size_t count)
> +{
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
> + struct tdx_cpuid_config_value *tmp;
> + ssize_t r;
> + u32 i;
> +
> + tmp = kmalloc(bin_attr->size, GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
> +
> + for (i = 0; i < sysinfo->num_cpuid_config; i++) {
> + struct tdx_cpuid_config *c = &sysinfo->cpuid_configs[i];
> + struct tdx_cpuid_config_value *value = (struct tdx_cpuid_config_value *)&c->eax;
> +
> + memcpy(tmp + i, value, sizeof(*value));
> + }
> +
> + r = memory_read_from_buffer(buf, count, &offset, tmp, bin_attr->size);
> + kfree(tmp);
> + return r;
> +}
> +
> +TDX_METADATA_ATTR(cpuid_values, TDX_METADATA_CPUID_VALUES_NAME, 0);
> +
> +static struct bin_attribute *tdx_metadata_attrs[] = {
> + &tdx_metadata_attributes_fixed0,
> + &tdx_metadata_attributes_fixed1,
> + &tdx_metadata_xfam_fixed0,
> + &tdx_metadata_xfam_fixed1,
> + &tdx_metadata_num_cpuid_config,
> + &tdx_metadata_cpuid_leaves,
> + &tdx_metadata_cpuid_values,
> + NULL,
> +};
> +
> +static const struct attribute_group tdx_metadata_attr_group = {
> + .bin_attrs = tdx_metadata_attrs,
> +};
> +
> +static int tdx_sysfs_init(void)
> +{
> + struct tdsysinfo_struct *sysinfo;
> + int ret;
> +
> + tdx_kobj = kobject_create_and_add("tdx", firmware_kobj);
> + if (!tdx_kobj) {
> + pr_err("kobject_create_and_add tdx failed\n");
> + return -EINVAL;
> + }
> +
> + tdx_module_kobj = kobject_create_and_add("tdx_module", tdx_kobj);
> + if (!tdx_module_kobj) {
> + pr_err("kobject_create_and_add tdx_module failed\n");
> + return -EINVAL;
> + }
> + tdx_metadata_kobj = kobject_create_and_add("metadata", tdx_module_kobj);
> + if (!tdx_metadata_kobj) {
> + pr_err("Sysfs exporting tdx global metadata failed %d\n", ret);
> + return -EINVAL;
> + }
> +
> + sysinfo = &PADDED_STRUCT(tdsysinfo);
> + tdx_metadata_cpuid_leaves.size = sysinfo->num_cpuid_config *
> + sizeof(struct tdx_cpuid_config_leaf);
> + tdx_metadata_cpuid_values.size = sysinfo->num_cpuid_config *
> + sizeof(struct tdx_cpuid_config_value);
> + ret = sysfs_create_group(tdx_metadata_kobj, &tdx_metadata_attr_group);
> + if (ret)
> + pr_err("Sysfs exporting tdx module attributes failed %d\n", ret);
> +
> + return ret;
> +}
> +#endif
> diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
> index db0cbcceb5b3..a48f38fe6cc4 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.h
> +++ b/arch/x86/virt/vmx/tdx/tdx.h
> @@ -93,4 +93,22 @@ struct tdmr_info_list {
> int max_tdmrs; /* How many 'tdmr_info's are allocated */
> };
>
> +/* TDX metadata base field id. */
> +#define TDX_METADATA_ATTRIBUTES_FIXED0 0x1900000300000000ULL
> +#define TDX_METADATA_ATTRIBUTES_FIXED1 0x1900000300000001ULL
> +#define TDX_METADATA_XFAM_FIXED0 0x1900000300000002ULL
> +#define TDX_METADATA_XFAM_FIXED1 0x1900000300000003ULL
> +#define TDX_METADATA_NUM_CPUID_CONFIG 0x9900000100000004ULL
> +#define TDX_METADATA_CPUID_LEAVES 0x9900000300000400ULL
> +#define TDX_METADATA_CPUID_VALUES 0x9900000300000500ULL
> +
> +/* File name for sysfs: hex with lower case. */
> +#define TDX_METADATA_ATTRIBUTES_FIXED0_NAME "1900000300000000"
> +#define TDX_METADATA_ATTRIBUTES_FIXED1_NAME "1900000300000001"
> +#define TDX_METADATA_XFAM_FIXED0_NAME "1900000300000002"
> +#define TDX_METADATA_XFAM_FIXED1_NAME "1900000300000003"
> +#define TDX_METADATA_NUM_CPUID_CONFIG_NAME "9900000100000004"
> +#define TDX_METADATA_CPUID_LEAVES_NAME "9900000300000400"
> +#define TDX_METADATA_CPUID_VALUES_NAME "9900000300000500"
> +
> #endif
On Wed, 29 Mar 2023 16:32:58 -0700
Isaku Yamahata <[email protected]> wrote:
> On Sat, Mar 25, 2023 at 08:13:26PM +0200,
> Zhi Wang <[email protected]> wrote:
>
> > On Sun, 12 Mar 2023 10:55:42 -0700
> > [email protected] wrote:
> >
> > > From: Isaku Yamahata <[email protected]>
> > >
> > > TDX has its own limitation on the maximum number of vcpus that the guest
> > > can accommodate. Allow x86 kvm backend to implement its own KVM_ENABLE_CAP
> > > handler and implement TDX backend for KVM_CAP_MAX_VCPUS. user space VMM,
> > > e.g. qemu, can specify its value instead of KVM_MAX_VCPUS.
> > >
> >
> > I think enabling the cap here is actually "configuring the cap". KVM_CAP_MAX
> > _VCPUS is actually always enabled whether userspace enables it or not. It
> > would be nice to configure of the max VCPUS in kvm_arch_vm_ioctl() where
> > routines of configuring a VM should belong. E.g. KVM_SET_MAX_VCPUS.
>
> I'm not sure I understand your point. Although KVM_ENABLE_CAP sounds like
> only on/off feature, but it isn't. It's also used to set parameters. For
> example, KVM_CAP_MAX_VCPU_ID.
>
Yes, I understand your point. But what has been there might not be right as
well. That doesn't smell right as "enable" is for something which is previously
"disabled". I understand that there can be some caps require configuration
when being enabled. But later, for those caps which don't have "on/off"
state, KVM_ENABLE_CAP doesn't actually enable a feature, it is just
configuring a feature. It seems like the KVM_ENABLE_CAP has been mis-used
little by little in the history. Also, I don't find KVM_DISABLE_CAP
accordingly. So KVM_ENABLE_CAP is actually used as "KVM_SET_CAP".
I realize it is not realistic to solve the problem in this patch series.
You can keep the current approach.
> KVM_SET_XXX is for run time feature. But the maxium number of vcpus is not
> runtime changable. Set it at vm creation.
Hi Like:
Would you mind to take a look on this patch? It would be nice to have
a r-b also from you. :)
On Sun, 12 Mar 2023 10:55:45 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> Because TDX KVM doesn't support PMU yet (it's future work of TDX KVM
> support as another patch series) and pmu_intel.c touches vmx specific
> structure in vcpu initialization, as workaround add dummy structure to
> struct vcpu_tdx and pmu_intel.c can ignore TDX case.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/kvm/vmx/pmu_intel.c | 46 +++++++++++++++++++++++++++++++++++-
> arch/x86/kvm/vmx/pmu_intel.h | 28 ++++++++++++++++++++++
> arch/x86/kvm/vmx/tdx.h | 8 ++++++-
> arch/x86/kvm/vmx/vmx.c | 2 +-
> arch/x86/kvm/vmx/vmx.h | 32 +------------------------
> 5 files changed, 82 insertions(+), 34 deletions(-)
> create mode 100644 arch/x86/kvm/vmx/pmu_intel.h
>
> diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
> index e8a3be0b9df9..df1f4ddfa72d 100644
> --- a/arch/x86/kvm/vmx/pmu_intel.c
> +++ b/arch/x86/kvm/vmx/pmu_intel.c
> @@ -19,6 +19,7 @@
> #include "lapic.h"
> #include "nested.h"
> #include "pmu.h"
> +#include "tdx.h"
>
> #define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
>
> @@ -40,6 +41,26 @@ static struct {
> /* mapping between fixed pmc index and intel_arch_events array */
> static int fixed_pmc_events[] = {1, 0, 7};
>
> +struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu)
> +{
> +#ifdef CONFIG_INTEL_TDX_HOST
> + if (is_td_vcpu(vcpu))
> + return &to_tdx(vcpu)->lbr_desc;
> +#endif
> +
> + return &to_vmx(vcpu)->lbr_desc;
> +}
> +
> +struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
> +{
> +#ifdef CONFIG_INTEL_TDX_HOST
> + if (is_td_vcpu(vcpu))
> + return &to_tdx(vcpu)->lbr_desc.records;
> +#endif
> +
> + return &to_vmx(vcpu)->lbr_desc.records;
> +}
> +
> static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
> {
> struct kvm_pmc *pmc;
> @@ -172,6 +193,23 @@ static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
> return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
> }
>
> +bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu)
> +{
> + if (is_td_vcpu(vcpu))
> + return false;
> + return cpuid_model_is_consistent(vcpu);
> +}
> +
> +bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
> +{
> + struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
> +
> + if (is_td_vcpu(vcpu))
> + return false;
> +
> + return lbr->nr && (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_LBR_FMT);
> +}
> +
> static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index)
> {
> struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu);
> @@ -282,6 +320,9 @@ int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu)
> PERF_SAMPLE_BRANCH_USER,
> };
>
> + if (WARN_ON_ONCE(is_td_vcpu(vcpu)))
> + return 0;
> +
> if (unlikely(lbr_desc->event)) {
> __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
> return 0;
> @@ -591,7 +632,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
> INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
>
> perf_capabilities = vcpu_get_perf_capabilities(vcpu);
> - if (cpuid_model_is_consistent(vcpu) &&
> + if (intel_pmu_lbr_is_compatible(vcpu) &&
> (perf_capabilities & PMU_CAP_LBR_FMT))
> x86_perf_get_lbr(&lbr_desc->records);
> else
> @@ -647,6 +688,9 @@ static void intel_pmu_reset(struct kvm_vcpu *vcpu)
> struct kvm_pmc *pmc = NULL;
> int i;
>
> + if (is_td_vcpu(vcpu))
> + return;
> +
> for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) {
> pmc = &pmu->gp_counters[i];
>
> diff --git a/arch/x86/kvm/vmx/pmu_intel.h b/arch/x86/kvm/vmx/pmu_intel.h
> new file mode 100644
> index 000000000000..66bba47c1269
> --- /dev/null
> +++ b/arch/x86/kvm/vmx/pmu_intel.h
> @@ -0,0 +1,28 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __KVM_X86_VMX_PMU_INTEL_H
> +#define __KVM_X86_VMX_PMU_INTEL_H
> +
> +struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu);
> +struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu);
> +
> +bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu);
> +bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu);
> +int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu);
> +
> +struct lbr_desc {
> + /* Basic info about guest LBR records. */
> + struct x86_pmu_lbr records;
> +
> + /*
> + * Emulate LBR feature via passthrough LBR registers when the
> + * per-vcpu guest LBR event is scheduled on the current pcpu.
> + *
> + * The records may be inaccurate if the host reclaims the LBR.
> + */
> + struct perf_event *event;
> +
> + /* True if LBRs are marked as not intercepted in the MSR bitmap */
> + bool msr_passthrough;
> +};
> +
> +#endif /* __KVM_X86_VMX_PMU_INTEL_H */
> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
> index 1e00e75b1c5e..5728820fed5e 100644
> --- a/arch/x86/kvm/vmx/tdx.h
> +++ b/arch/x86/kvm/vmx/tdx.h
> @@ -4,6 +4,7 @@
>
> #ifdef CONFIG_INTEL_TDX_HOST
>
> +#include "pmu_intel.h"
> #include "tdx_ops.h"
>
> struct kvm_tdx {
> @@ -21,7 +22,12 @@ struct kvm_tdx {
>
> struct vcpu_tdx {
> struct kvm_vcpu vcpu;
> - /* TDX specific members follow. */
> +
> + /*
> + * Dummy to make pmu_intel not corrupt memory.
> + * TODO: Support PMU for TDX. Future work.
> + */
> + struct lbr_desc lbr_desc;
> };
>
> static inline bool is_td(struct kvm *kvm)
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index d23830d92f61..f9e9fd7fde2c 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -2432,7 +2432,7 @@ int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> if ((data & PMU_CAP_LBR_FMT) !=
> (kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT))
> return 1;
> - if (!cpuid_model_is_consistent(vcpu))
> + if (!intel_pmu_lbr_is_compatible(vcpu))
> return 1;
> }
> if (data & PERF_CAP_PEBS_FORMAT) {
> diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
> index 2acdc54bc34b..1d15c3c2751b 100644
> --- a/arch/x86/kvm/vmx/vmx.h
> +++ b/arch/x86/kvm/vmx/vmx.h
> @@ -11,6 +11,7 @@
> #include "capabilities.h"
> #include "../kvm_cache_regs.h"
> #include "posted_intr.h"
> +#include "pmu_intel.h"
> #include "vmcs.h"
> #include "vmx_ops.h"
> #include "../cpuid.h"
> @@ -105,22 +106,6 @@ static inline bool intel_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
> return pmu->version > 1;
> }
>
> -struct lbr_desc {
> - /* Basic info about guest LBR records. */
> - struct x86_pmu_lbr records;
> -
> - /*
> - * Emulate LBR feature via passthrough LBR registers when the
> - * per-vcpu guest LBR event is scheduled on the current pcpu.
> - *
> - * The records may be inaccurate if the host reclaims the LBR.
> - */
> - struct perf_event *event;
> -
> - /* True if LBRs are marked as not intercepted in the MSR bitmap */
> - bool msr_passthrough;
> -};
> -
> /*
> * The nested_vmx structure is part of vcpu_vmx, and holds information we need
> * for correct emulation of VMX (i.e., nested VMX) on this vcpu.
> @@ -650,21 +635,6 @@ static __always_inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
> return container_of(vcpu, struct vcpu_vmx, vcpu);
> }
>
> -static inline struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu)
> -{
> - return &to_vmx(vcpu)->lbr_desc;
> -}
> -
> -static inline struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
> -{
> - return &vcpu_to_lbr_desc(vcpu)->records;
> -}
> -
> -static inline bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
> -{
> - return !!vcpu_to_lbr_records(vcpu)->nr;
> -}
> -
> void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu);
> int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu);
> void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu);
On Wed, 29 Mar 2023 18:01:53 -0700
Isaku Yamahata <[email protected]> wrote:
> Hi, thanks for review.
>
> On Sun, Mar 26, 2023 at 02:09:36PM +0300,
> Zhi Wang <[email protected]> wrote:
>
> > On Sun, 12 Mar 2023 10:55:43 -0700
> > [email protected] wrote:
>
> > > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > > index 8b02e605cfb5..3ede8a726b47 100644
> > > --- a/arch/x86/kvm/vmx/tdx.c
> > > +++ b/arch/x86/kvm/vmx/tdx.c
> > > @@ -5,8 +5,9 @@
> > >
> > > #include "capabilities.h"
> > > #include "x86_ops.h"
> > > -#include "x86.h"
> > > #include "tdx.h"
> > > +#include "tdx_ops.h"
> > > +#include "x86.h"
> > >
> > > #undef pr_fmt
> > > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> > > @@ -46,11 +47,276 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
> > > return r;
> > > }
> > >
> > > +struct tdx_info {
> > > + u8 nr_tdcs_pages;
> > > +};
> > > +
> > > +/* Info about the TDX module. */
> > > +static struct tdx_info tdx_info;
> > > +
> > > +/*
> > > + * Some TDX SEAMCALLs (TDH.MNG.CREATE, TDH.PHYMEM.CACHE.WB,
> > > + * TDH.MNG.KEY.RECLAIMID, TDH.MNG.KEY.FREEID etc) tries to acquire a global lock
> > > + * internally in TDX module. If failed, TDX_OPERAND_BUSY is returned without
> > > + * spinning or waiting due to a constraint on execution time. It's caller's
> > > + * responsibility to avoid race (or retry on TDX_OPERAND_BUSY). Use this mutex
> > > + * to avoid race in TDX module because the kernel knows better about scheduling.
> > > + */
> > > +static DEFINE_MUTEX(tdx_lock);
> > > +static struct mutex *tdx_mng_key_config_lock;
> > > +
> > > +static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
> > > +{
> > > + return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
> > > +}
> > > +
> > > +static inline bool is_td_created(struct kvm_tdx *kvm_tdx)
> > > +{
> > > + return kvm_tdx->tdr_pa;
> > > +}
> > > +
> > > +static inline void tdx_hkid_free(struct kvm_tdx *kvm_tdx)
> > > +{
> > > + tdx_guest_keyid_free(kvm_tdx->hkid);
> > > + kvm_tdx->hkid = 0;
> > > +}
> > > +
> > > +static inline bool is_hkid_assigned(struct kvm_tdx *kvm_tdx)
> > > +{
> > > + return kvm_tdx->hkid > 0;
> > > +}
> > > +
> > > int tdx_hardware_enable(void)
> > > {
> > > return tdx_cpu_enable();
> > > }
> > >
> > > +static void tdx_clear_page(unsigned long page_pa)
> > > +{
> > > + const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
> > > + void *page = __va(page_pa);
> > > + unsigned long i;
> > > +
> > > + if (!cpu_feature_enabled(X86_FEATURE_MOVDIR64B)) {
> > > + clear_page(page);
> > > + return;
> > > + }
> >
> > Is it possbile to have a TDX machine without MOVDIR64B support? I am not sure
> > if there is any other way for the kernel to clear the posioned cache line.
> >
> > If not, there should be a warn/bug at least and check if MOVDIR64B support
> > when initializing the TDX.
>
> Because the latest TDX specification uses movdir64b, it's safe for TDX
> to assume movdir64b.
> I'll add the check to TDX initialization part and drop it from here.
>
>
> > > +void tdx_mmu_release_hkid(struct kvm *kvm)
> > > +{
> > > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > > + cpumask_var_t packages;
> > > + bool cpumask_allocated;
> > > + u64 err;
> > > + int ret;
> > > + int i;
> > > +
> > > + if (!is_hkid_assigned(kvm_tdx))
> > > + return;
> > > +
> > > + if (!is_td_created(kvm_tdx))
> > > + goto free_hkid;
> > > +
> > > + cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
> > > + cpus_read_lock();
> > > + for_each_online_cpu(i) {
> > > + if (cpumask_allocated &&
> > > + cpumask_test_and_set_cpu(topology_physical_package_id(i),
> > > + packages))
> > > + continue;
> >
> > Is this necessary to check cpumask_allocated in the while loop? if cpumask
> > is not succefully allocated, wouldn't it be better to bail out just after
> > it?
>
> No because we can't return error here. It's better to do in-efficiently freeing
> resources instead of leak.
>
> We can move the check out of loop. But it would be ugly
> (if () {cpu loop} else {cpu loop} ) and this function isn't performance
> critical. Also I think it's okay to depend on compiler optimization for loop
> invariant. My compiler didn't optimize it in this case, though.
>
Do you mean the tdh_mng_key_freeid() is still required if failing to allocate
the cpumask var and do TDH.PHYMEM_CACHE_WB(WBINVD) on each CPU?
Out of curiosity, I took a look on the TDX module source code [1], it seems TDX
module has an additional check in TDH.MNG.KEY.FREEID. TDH.MNG.VPFLUSHDONE [2]
will mark the pending wbinvd in a bitmap:
...
/**
* Create the WBINVD_BITMAP per-package.
* Set to 1 num_of_pkgs bits from the LSB
*/
global_data_ptr->kot.entries[curr_hkid].wbinvd_bitmap = global_data_ptr->pkg_config_bitmap; /* <----HERE */
// Set new TD life cycle state
tdr_ptr->management_fields.lifecycle_state = TD_BLOCKED;
// Set the proper new KOT entry state
global_data_ptr->kot.entries[curr_hkid].state = (uint8_t)KOT_STATE_HKID_FLUSHED;
...
And TDH.MNG.KEY.FREEID [3] will check if the pending WBINVD has been performed:
...
/**
* If TDH_PHYMEM_CACHE_WB was executed on all packages/cores,
* set the KOT entry, set the KOT entry state to HKID_FREE.
*/
curr_hkid = tdr_ptr->key_management_fields.hkid;
tdx_debug_assert(global_data_ptr->kot.entr/ies[curr_hkid].state == KOT_STATE_HKID_FLUSHED);
if (global_data_ptr->kot.entries[curr_hkid].wbinvd_bitmap != 0) /* HERE */
{
TDX_ERROR("CACHEWB is not complete for this HKID (=%x)\n", curr_hkid);
return_val = TDX_WBCACHE_NOT_COMPLETE;
goto EXIT;
}
...
Guess the conclusion is: if TDH.PHYMEM.CACHE.WB is not performed on each
required CPU correctly, TDH.MNG.KEY.FREEID will fail as well. A leak seems
the only option (none of us likes a leak, but...).
It would be better that:
1) Leave a comment about the finding above in the code to explain why leak
happens (It is always nice to explain the reason of a leak). One sentence
will be good enough.
2) If failing to allocate the cpumask, bail out (with the findings above)
...
cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
if (!cpumask_allocated)
return;
...
3) As the reason of the leak will be explained in tdx_mmu_release_hkid(),
leaving a pointer in the comment in tdx_vm_free() to refer to
tdx_mmu_release_hkid() would be enough, like:
...
/*
* Can't reclaim or free TD pages if teardown failed in
* tdx_mmu_release_hkid().
*/
if (is_hkid_assigned(kvm_tdx))
return;
...
[1] https://downloadmirror.intel.com/738876/tdx-module-v1.0.01.01.zip
[2] tdx-module/src/vmm_dispatcher/api_calls/tdh_mng_vpflushdone.c
[3] tdx-module/src/vmm_dispatcher/api_calls/tdh_mng_key_freeid.c
>
> > > +
> > > + /*
> > > + * We can destroy multiple the guest TDs simultaneously.
> > > + * Prevent tdh_phymem_cache_wb from returning TDX_BUSY by
> > > + * serialization.
> > > + */
> > > + mutex_lock(&tdx_lock);
> > > + ret = smp_call_on_cpu(i, tdx_do_tdh_phymem_cache_wb, NULL, 1);
> > > + mutex_unlock(&tdx_lock);
> > > + if (ret)
> > > + break;
> > > + }
> > > + cpus_read_unlock();
> > > + free_cpumask_var(packages);
> > > +
> > > + mutex_lock(&tdx_lock);
> > > + err = tdh_mng_key_freeid(kvm_tdx->tdr_pa);
> > > + mutex_unlock(&tdx_lock);
> > > + if (WARN_ON_ONCE(err)) {
> > > + pr_tdx_error(TDH_MNG_KEY_FREEID, err, NULL);
> > > + pr_err("tdh_mng_key_freeid failed. HKID %d is leaked.\n",
> > > + kvm_tdx->hkid);
> > > + return;
> > > + }
> > > +
> > > +free_hkid:
> > > + tdx_hkid_free(kvm_tdx);
> > > +}
> > > +
> > > +void tdx_vm_free(struct kvm *kvm)
> > > +{
> > > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > > + int i;
> > > +
> > > + /* Can't reclaim or free TD pages if teardown failed. */
> > > + if (is_hkid_assigned(kvm_tdx))
> > > + return;
> > > +
> >
> > Better to explain why, as it is common to think even the teardown failed, we
> > should still try to reclaim the pages as many as we can.
>
> Ok, here is the updated comment.
> /*
> * tdx_mmu_release_hkid() failed to reclaim HKID. Something went wrong
> * heavily with TDX module. Give up freeing TD pages. As the function
> * already warned, don't warn it again.
> */
On 3/31/2023 8:44 PM, Zhi Wang wrote:
> On Thu, 30 Mar 2023 17:18:03 -0700
> Isaku Yamahata <[email protected]> wrote:
>
>> On Wed, Mar 29, 2023 at 04:17:22PM -0700,
>> Isaku Yamahata <[email protected]> wrote:
>>
>>> On Sat, Mar 25, 2023 at 10:43:06AM +0200,
>>> Zhi Wang <[email protected]> wrote:
>>>
>>>> On Sun, 12 Mar 2023 10:55:40 -0700
>>>> [email protected] wrote:
>>>>
>>>> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
>>>> does not use it at all and all the system-scoped ioctl of SNP going through
>>>> the CCP driver. So getting system-scope information of TDX/SNP will end up
>>>> differently.
>>>>
>>>> Any thought, Sean? Moving getting SNP system-wide information to
>>>> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
>>>> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
>>>
>>> We only need global parameters of the TDX module, and we don't interact with TDX
>>> module at this point. One alternative is to export those parameters via sysfs.
>>> Also the existence of the sysfs node indicates that the TDX module is
>>> loaded(initialized?) or not in addition to boot log. Thus we can drop system
>>> scope one.
>>> What do you think?
>>>
>
> I like this idea and the patch below, it feels right for me now. It would be nice
> if more folks can chime in and comment.
SYSFS option requires CONFIG_SYSFS, which reqiures CONFIG_KVM_TDX to
select CONFIG_SYSFS.
>>> Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
>>> KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
>>> I don't think it can be split out to independent driver.
>>
>
> They can stay in KVM as they are KVM-specific. SNP also has KVM-specific ioctls
> which wraps the SEV driver calls. At this level, both TDX and SNP go their specific
> implementation without more abstraction other than KVM_ENCRYPT_MEMORY_OP. Their
> strategies are aligned.
>
> The problem of the previous approach was the abstraction that no other implementation
> is using it. It is like, TDX wants a higher abstraction to cover both TDX and SNP,
> but SNP is not using it, which makes the abstraction looks strange.
Note, before this TDX enabling series, KVM_MEMORY_ENCRYPT_OP is a VM
scope ioctl, that only serves for SEV and no other implementation uses
it. I see no reason why cannot introduce a new IOCTL in x86 KVM that
serves only one vendor.
We choose KVM_MEMORY_ENCRYPT_OP for TDX platform scope, just because we
reuse KVM_MEMORY_ENCRYPT_OP for TDX VM-scope and extend it to TDX vcpu
scope. It's just to avoid defining a new IOCTL number.
We can rename it to KVM_GET_CC_CAPABILITIES, and even return different
capabilities based on VM type. And even, if SNP wants to use it, I think
it can wrap SNP driver calls inside this IOCTL?
kvm.ko is special that it needs to serve two vendors. Sometime it's
unaviodable that an interface is only used by one vendor.
On Mon, 3 Apr 2023 11:46:15 +0800
Xiaoyao Li <[email protected]> wrote:
> On 3/31/2023 8:44 PM, Zhi Wang wrote:
> > On Thu, 30 Mar 2023 17:18:03 -0700
> > Isaku Yamahata <[email protected]> wrote:
> >
> >> On Wed, Mar 29, 2023 at 04:17:22PM -0700,
> >> Isaku Yamahata <[email protected]> wrote:
> >>
> >>> On Sat, Mar 25, 2023 at 10:43:06AM +0200,
> >>> Zhi Wang <[email protected]> wrote:
> >>>
> >>>> On Sun, 12 Mar 2023 10:55:40 -0700
> >>>> [email protected] wrote:
> >>>>
> >>>> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> >>>> does not use it at all and all the system-scoped ioctl of SNP going through
> >>>> the CCP driver. So getting system-scope information of TDX/SNP will end up
> >>>> differently.
> >>>>
> >>>> Any thought, Sean? Moving getting SNP system-wide information to
> >>>> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> >>>> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
> >>>
> >>> We only need global parameters of the TDX module, and we don't interact with TDX
> >>> module at this point. One alternative is to export those parameters via sysfs.
> >>> Also the existence of the sysfs node indicates that the TDX module is
> >>> loaded(initialized?) or not in addition to boot log. Thus we can drop system
> >>> scope one.
> >>> What do you think?
> >>>
> >
> > I like this idea and the patch below, it feels right for me now. It would be nice
> > if more folks can chime in and comment.
>
> SYSFS option requires CONFIG_SYSFS, which reqiures CONFIG_KVM_TDX to
> select CONFIG_SYSFS.
>
> >>> Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
> >>> KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
> >>> I don't think it can be split out to independent driver.
> >>
> >
> > They can stay in KVM as they are KVM-specific. SNP also has KVM-specific ioctls
> > which wraps the SEV driver calls. At this level, both TDX and SNP go their specific
> > implementation without more abstraction other than KVM_ENCRYPT_MEMORY_OP. Their
> > strategies are aligned.
> >
> > The problem of the previous approach was the abstraction that no other implementation
> > is using it. It is like, TDX wants a higher abstraction to cover both TDX and SNP,
> > but SNP is not using it, which makes the abstraction looks strange.
>
> Note, before this TDX enabling series, KVM_MEMORY_ENCRYPT_OP is a VM
> scope ioctl, that only serves for SEV and no other implementation uses
> it. I see no reason why cannot introduce a new IOCTL in x86 KVM that
> serves only one vendor.
>
My point is: time is different. When KVM_MEMORY_ENCRYPT_OP is there,
there was *only* one vendor and SEV/SNP didn't know how the future vendor
is going to use the ioctl. That is a reasonable case an generic ioctl can
have one vendor to back up.
The background here is: now another vendor is coming and there are going to
be two vendors. The two vendors' flows are much clearer than early stage.
Like, they know which flow is going to be used by each other.
With these kept in mind, IMHO, it is not appropriate to introduce
an generic ioctl that only one vendor is going to use, meanwhile
we have already known another vendor is not going to use it.
Defining a new userspace ABI is a serious thing and it is not an early
stage anymore. Actually I think it is the best time to see how the
code infrastructure should be re-purposed at this time.
> We choose KVM_MEMORY_ENCRYPT_OP for TDX platform scope, just because we
> reuse KVM_MEMORY_ENCRYPT_OP for TDX VM-scope and extend it to TDX vcpu
> scope. It's just to avoid defining a new IOCTL number.
>
> We can rename it to KVM_GET_CC_CAPABILITIES, and even return different
> capabilities based on VM type. And even, if SNP wants to use it, I think
> it can wrap SNP driver calls inside this IOCTL?
>
I am not opposed to this option as it shows effort to improve it and it
is constructive. But this needs to be figured out with AMD folks and
maintainers. E.g. what should be the best CC ioctl scheme for KVM?
vendor-specific or generic, which brings better benefit for the userspace,
and less maintenance burden.
Back to the reason why I think a vendor-specific sysinfo interface for TDX
is necessary:
1) SEV driver has been there for quite some time. Unless people thinks an
generic CC ioctl scheme is a way to go, then there will be motivation and
efforts putting on it. The efforts is not only about wrapping SEV ioctls,
it needs a systematic spec of generic CC ioctl scheme.
2) TDX doesn't have a driver like SEV and possibly not going to have one in
the future. For those non-KVM related control flow of TDX in future, they
can re-use this and stay away from KVM interface. (If vendor-specific
scheme is the future direction.)
> kvm.ko is special that it needs to serve two vendors. Sometime it's
> unaviodable that an interface is only used by one vendor.
I am afraid that in this case it is avoidable right?
On Sun, 12 Mar 2023 10:55:44 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> TDX requires additional parameters for TDX VM for confidential execution to
> protect its confidentiality of its memory contents and its CPU state from
> any other software, including VMM. When creating guest TD VM before
> creating vcpu, the number of vcpu, TSC frequency (that is same among
> vcpus. and it can't be changed.) CPUIDs which is emulated by the TDX
^ This sentence seems broken. "
> module. It means guest can trust those CPUIDs. and sha384 values for
> measurement.
>
> Add new subcommand, KVM_TDX_INIT_VM, to pass parameters for TDX guest. It
> assigns encryption key to the TDX guest for memory encryption. TDX
> encrypts memory per-guest bases. It assigns device model passes per-VM
> parameters for the TDX guest. The maximum number of vcpus, tsc frequency
> (TDX guest has fised VM-wide TSC frequency. not per-vcpu. The TDX guest
> can not change it.), attributes (production or debug), available extended
> features (which is reflected into guest XCR0, IA32_XSS MSR), cpuids, sha384
> measurements, and etc.
>
> This subcommand is called before creating vcpu and KVM_SET_CPUID2, i.e.
> cpuids configurations aren't available yet. So CPUIDs configuration values
> needs to be passed in struct kvm_tdx_init_vm. It's device model
> responsibility to make this cpuid config for KVM_TDX_INIT_VM and
> KVM_SET_CPUID2.
>
> Signed-off-by: Xiaoyao Li <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> Changes from v11 to v12
> - ABI change. Changes struct kvm_tdx_init_vm layout
> ---
> arch/x86/include/asm/tdx.h | 3 +
> arch/x86/include/uapi/asm/kvm.h | 24 +++
> arch/x86/kvm/cpuid.c | 7 +
> arch/x86/kvm/cpuid.h | 2 +
> arch/x86/kvm/vmx/tdx.c | 247 ++++++++++++++++++++++++--
> arch/x86/kvm/vmx/tdx.h | 18 ++
> tools/arch/x86/include/uapi/asm/kvm.h | 33 ++++
> 7 files changed, 324 insertions(+), 10 deletions(-)
>
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index 05870e5ed131..bd09b03d7edd 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -101,6 +101,9 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
> #endif /* CONFIG_INTEL_TDX_GUEST && CONFIG_KVM_GUEST */
>
> #ifdef CONFIG_INTEL_TDX_HOST
> +
> +/* -1 indicates CPUID leaf with no sub-leaves. */
> +#define TDX_CPUID_NO_SUBLEAF ((u32)-1)
> struct tdx_cpuid_config {
> u32 leaf;
> u32 sub_leaf;
> diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
> index af4c5bd0af1c..68e8d544afe5 100644
> --- a/arch/x86/include/uapi/asm/kvm.h
> +++ b/arch/x86/include/uapi/asm/kvm.h
> @@ -565,6 +565,7 @@ struct kvm_pmu_event_filter {
> /* Trust Domain eXtension sub-ioctl() commands. */
> enum kvm_tdx_cmd_id {
> KVM_TDX_CAPABILITIES = 0,
> + KVM_TDX_INIT_VM,
>
> KVM_TDX_CMD_NR_MAX,
> };
> @@ -610,4 +611,27 @@ struct kvm_tdx_capabilities {
> struct kvm_tdx_cpuid_config cpuid_configs[0];
> };
>
> +struct kvm_tdx_init_vm {
> + __u64 attributes;
> + __u64 mrconfigid[6]; /* sha384 digest */
> + __u64 mrowner[6]; /* sha384 digest */
> + __u64 mrownerconfig[6]; /* sha348 digest */
> + /*
> + * For future extensibility to make sizeof(struct kvm_tdx_init_vm) = 8KB.
> + * This should be enough given sizeof(TD_PARAMS) = 1024.
> + * 8KB was chosen given because
> + * sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES(=256) = 8KB.
> + */
> + __u64 reserved[1004];
> +
> + /*
> + * KVM_TDX_INIT_VM is called before vcpu creation, thus before
> + * KVM_SET_CPUID2.
> + * This configuration supersedes KVM_SET_CPUID2s for VCPUs. The user
> + * space VMM, e.g. qemu, should make KVM_SET_CPUID2 consistent with this
> + * values.
^
It would be nice to have one more sentence to talk about the
consequence if QEMU configures different CPUIDs in KVM_TDX_INIT_VM and the later
SET_CPUID2.
> + */
> + struct kvm_cpuid2 cpuid;
> +};
> +
> #endif /* _ASM_X86_KVM_H */
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 599aebec2d52..9cda9a3a558a 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -1386,6 +1386,13 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
> return r;
> }
>
> +struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2( struct kvm_cpuid2 *cpuid,
> + u32 function, u32 index)
> +{
> + return cpuid_entry2_find(cpuid->entries, cpuid->nent, function, index);
> +}
> +EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry2);
> +
> struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
> u32 function, u32 index)
> {
> diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
> index b1658c0de847..a0e799297629 100644
> --- a/arch/x86/kvm/cpuid.h
> +++ b/arch/x86/kvm/cpuid.h
> @@ -13,6 +13,8 @@ void kvm_set_cpu_caps(void);
>
> void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
> void kvm_update_pv_runtime(struct kvm_vcpu *vcpu);
> +struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2(struct kvm_cpuid2 *cpuid,
> + u32 function, u32 index);
> struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
> u32 function, u32 index);
> struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 3ede8a726b47..496410ec6334 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -6,7 +6,6 @@
> #include "capabilities.h"
> #include "x86_ops.h"
> #include "tdx.h"
> -#include "tdx_ops.h"
> #include "x86.h"
>
> #undef pr_fmt
> @@ -303,18 +302,21 @@ static int tdx_do_tdh_mng_key_config(void *param)
> return 0;
> }
>
> -static int __tdx_td_init(struct kvm *kvm);
> -
> int tdx_vm_init(struct kvm *kvm)
> {
> + /*
> + * This function initializes only KVM software construct. It doesn't
> + * initialize TDX stuff, e.g. TDCS, TDR, TDCX, HKID etc.
> + * It is handled by KVM_TDX_INIT_VM, __tdx_td_init().
> + */
> +
> /*
> * TDX has its own limit of the number of vcpus in addition to
> * KVM_MAX_VCPUS.
> */
> kvm->max_vcpus = min(kvm->max_vcpus, TDX_MAX_VCPUS);
>
> - /* Place holder for TDX specific logic. */
> - return __tdx_td_init(kvm);
> + return 0;
> }
>
> int tdx_dev_ioctl(void __user *argp)
> @@ -368,9 +370,162 @@ int tdx_dev_ioctl(void __user *argp)
> return 0;
> }
>
> -static int __tdx_td_init(struct kvm *kvm)
> +static void setup_tdparams_eptp_controls(struct kvm_cpuid2 *cpuid, struct td_params *td_params)
> +{
> + const struct kvm_cpuid_entry2 *entry;
> + int max_pa = 36;
> +
> + entry = kvm_find_cpuid_entry2(cpuid, 0x80000008, 0);
> + if (entry)
> + max_pa = entry->eax & 0xff;
> +
> + td_params->eptp_controls = VMX_EPTP_MT_WB;
> + /*
> + * No CPU supports 4-level && max_pa > 48.
> + * "5-level paging and 5-level EPT" section 4.1 4-level EPT
> + * "4-level EPT is limited to translating 48-bit guest-physical
> + * addresses."
> + * cpu_has_vmx_ept_5levels() check is just in case.
> + */
> + if (cpu_has_vmx_ept_5levels() && max_pa > 48) {
> + td_params->eptp_controls |= VMX_EPTP_PWL_5;
> + td_params->exec_controls |= TDX_EXEC_CONTROL_MAX_GPAW;
> + } else {
> + td_params->eptp_controls |= VMX_EPTP_PWL_4;
> + }
> +}
> +
> +static void setup_tdparams_cpuids(const struct tdsysinfo_struct *tdsysinfo,
> + struct kvm_cpuid2 *cpuid,
> + struct td_params *td_params)
> +{
> + int i;
> +
> + /*
> + * td_params.cpuid_values: The number and the order of cpuid_value must
> + * be same to the one of struct tdsysinfo.{num_cpuid_config, cpuid_configs}
> + * It's assumed that td_params was zeroed.
> + */
> + for (i = 0; i < tdsysinfo->num_cpuid_config; i++) {
> + const struct tdx_cpuid_config *config = &tdsysinfo->cpuid_configs[i];
> + /* TDX_CPUID_NO_SUBLEAF in TDX CPUID_CONFIG means index = 0. */
> + u32 index = config->sub_leaf == TDX_CPUID_NO_SUBLEAF ? 0: config->sub_leaf;
> + const struct kvm_cpuid_entry2 *entry =
> + kvm_find_cpuid_entry2(cpuid, config->leaf, index);
> + struct tdx_cpuid_value *value = &td_params->cpuid_values[i];
> +
> + if (!entry)
> + continue;
> +
> + /*
> + * tdsysinfo.cpuid_configs[].{eax, ebx, ecx, edx}
> + * bit 1 means it can be configured to zero or one.
> + * bit 0 means it must be zero.
> + * Mask out non-configurable bits.
> + */
> + value->eax = entry->eax & config->eax;
> + value->ebx = entry->ebx & config->ebx;
> + value->ecx = entry->ecx & config->ecx;
> + value->edx = entry->edx & config->edx;
> + }
> +}
> +
> +static int setup_tdparams_xfam(struct kvm_cpuid2 *cpuid, struct td_params *td_params)
> +{
> + const struct kvm_cpuid_entry2 *entry;
> + u64 guest_supported_xcr0;
> + u64 guest_supported_xss;
> +
> + /* Setup td_params.xfam */
> + entry = kvm_find_cpuid_entry2(cpuid, 0xd, 0);
> + if (entry)
> + guest_supported_xcr0 = (entry->eax | ((u64)entry->edx << 32));
> + else
> + guest_supported_xcr0 = 0;
> + guest_supported_xcr0 &= kvm_caps.supported_xcr0;
> +
> + entry = kvm_find_cpuid_entry2(cpuid, 0xd, 1);
> + if (entry)
> + guest_supported_xss = (entry->ecx | ((u64)entry->edx << 32));
> + else
> + guest_supported_xss = 0;
> + /* PT can be exposed to TD guest regardless of KVM's XSS support */
> + guest_supported_xss &= (kvm_caps.supported_xss | XFEATURE_MASK_PT);
> +
> + td_params->xfam = guest_supported_xcr0 | guest_supported_xss;
> + if (td_params->xfam & XFEATURE_MASK_LBR) {
> + /*
> + * TODO: once KVM supports LBR(save/restore LBR related
> + * registers around TDENTER), remove this guard.
> + */
> + pr_warn("TD doesn't support LBR yet. KVM needs to save/restore "
> + "IA32_LBR_DEPTH properly.\n");
> + return -EOPNOTSUPP;
> + }
> +
> + if (td_params->xfam & XFEATURE_MASK_XTILE) {
> + /*
> + * TODO: once KVM supports AMX(save/restore AMX related
> + * registers around TDENTER), remove this guard.
> + */
> + pr_warn("TD doesn't support AMX yet. KVM needs to save/restore "
> + "IA32_XFD, IA32_XFD_ERR properly.\n");
> + return -EOPNOTSUPP;
> + }
> +
> + return 0;
> +}
> +
> +static int setup_tdparams(struct kvm *kvm, struct td_params *td_params,
> + struct kvm_tdx_init_vm *init_vm)
> +{
> + struct kvm_cpuid2 *cpuid = &init_vm->cpuid;
> + const struct tdsysinfo_struct *tdsysinfo;
> + int ret;
> +
> + tdsysinfo = tdx_get_sysinfo();
> + if (!tdsysinfo)
> + return -ENOTSUPP;
> + if (kvm->created_vcpus)
> + return -EBUSY;
> +
> + if (td_params->attributes & TDX_TD_ATTRIBUTE_PERFMON) {
> + /*
> + * TODO: save/restore PMU related registers around TDENTER.
> + * Once it's done, remove this guard.
> + */
> + pr_warn("TD doesn't support perfmon yet. KVM needs to save/restore "
> + "host perf registers properly.\n");
> + return -EOPNOTSUPP;
> + }
> +
> + td_params->max_vcpus = kvm->max_vcpus;
> + td_params->attributes = init_vm->attributes;
> + td_params->tsc_frequency = TDX_TSC_KHZ_TO_25MHZ(kvm->arch.default_tsc_khz);
> +
> + setup_tdparams_eptp_controls(cpuid, td_params);
> + setup_tdparams_cpuids(tdsysinfo, cpuid, td_params);
> + ret = setup_tdparams_xfam(cpuid, td_params);
> + if (ret)
> + return ret;
> +
> +#define MEMCPY_SAME_SIZE(dst, src) \
> + do { \
> + BUILD_BUG_ON(sizeof(dst) != sizeof(src)); \
> + memcpy((dst), (src), sizeof(dst)); \
> + } while (0)
> +
> + MEMCPY_SAME_SIZE(td_params->mrconfigid, init_vm->mrconfigid);
> + MEMCPY_SAME_SIZE(td_params->mrowner, init_vm->mrowner);
> + MEMCPY_SAME_SIZE(td_params->mrownerconfig, init_vm->mrownerconfig);
> +
> + return 0;
> +}
> +
> +static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params)
> {
> struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + struct tdx_module_output out;
> cpumask_var_t packages;
> unsigned long *tdcs_pa = NULL;
> unsigned long tdr_pa = 0;
> @@ -484,10 +639,13 @@ static int __tdx_td_init(struct kvm *kvm)
> }
> }
>
> - /*
> - * Note, TDH_MNG_INIT cannot be invoked here. TDH_MNG_INIT requires a dedicated
> - * ioctl() to define the configure CPUID values for the TD.
> - */
> + err = tdh_mng_init(kvm_tdx->tdr_pa, __pa(td_params), &out);
> + if (WARN_ON_ONCE(err)) {
> + pr_tdx_error(TDH_MNG_INIT, err, &out);
> + ret = -EIO;
> + goto teardown;
> + }
> +
> return 0;
>
> /*
> @@ -522,6 +680,72 @@ static int __tdx_td_init(struct kvm *kvm)
> return ret;
> }
>
> +static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd)
> +{
> + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> + struct kvm_tdx_init_vm *init_vm = NULL;
> + struct td_params *td_params = NULL;
> + int ret;
> +
> + BUILD_BUG_ON(sizeof(*init_vm) != 8 * 1024);
> + BUILD_BUG_ON(sizeof(struct td_params) != 1024);
> +
> + if (is_hkid_assigned(kvm_tdx))
> + return -EINVAL;
> +
> + if (cmd->flags)
> + return -EINVAL;
> +
> + init_vm = kzalloc(sizeof(*init_vm) +
> + sizeof(init_vm->cpuid.entries[0]) * KVM_MAX_CPUID_ENTRIES,
> + GFP_KERNEL);
> + if (!init_vm)
> + return -ENOMEM;
> + if (copy_from_user(init_vm, (void __user *)cmd->data, sizeof(*init_vm))) {
> + ret = -EFAULT;
> + goto out;
> + }
> + if (init_vm->cpuid.nent > KVM_MAX_CPUID_ENTRIES) {
> + ret = -E2BIG;
> + goto out;
> + }
> + if (copy_from_user(init_vm->cpuid.entries,
> + (void __user *)cmd->data + sizeof(*init_vm),
> + sizeof(init_vm->cpuid.entries[0]) * init_vm->cpuid.nent)) {
> + ret = -EFAULT;
> + goto out;
> + }
> +
> + if (init_vm->cpuid.padding) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + td_params = kzalloc(sizeof(struct td_params), GFP_KERNEL);
> + if (!td_params) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + ret = setup_tdparams(kvm, td_params, init_vm);
> + if (ret)
> + goto out;
> +
> + ret = __tdx_td_init(kvm, td_params);
> + if (ret)
> + goto out;
> +
> + kvm_tdx->tsc_offset = td_tdcs_exec_read64(kvm_tdx, TD_TDCS_EXEC_TSC_OFFSET);
> + kvm_tdx->attributes = td_params->attributes;
> + kvm_tdx->xfam = td_params->xfam;
> +
> +out:
> + /* kfree() accepts NULL. */
> + kfree(init_vm);
> + kfree(td_params);
> + return ret;
> +}
> +
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> {
> struct kvm_tdx_cmd tdx_cmd;
> @@ -535,6 +759,9 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> mutex_lock(&kvm->lock);
>
> switch (tdx_cmd.id) {
> + case KVM_TDX_INIT_VM:
> + r = tdx_td_init(kvm, &tdx_cmd);
> + break;
> default:
> r = -EINVAL;
> goto out;
> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
> index 4b790503e43e..1e00e75b1c5e 100644
> --- a/arch/x86/kvm/vmx/tdx.h
> +++ b/arch/x86/kvm/vmx/tdx.h
> @@ -12,7 +12,11 @@ struct kvm_tdx {
> unsigned long tdr_pa;
> unsigned long *tdcs_pa;
>
> + u64 attributes;
> + u64 xfam;
> int hkid;
> +
> + u64 tsc_offset;
> };
>
> struct vcpu_tdx {
> @@ -39,6 +43,20 @@ static inline struct vcpu_tdx *to_tdx(struct kvm_vcpu *vcpu)
> {
> return container_of(vcpu, struct vcpu_tdx, vcpu);
> }
> +
> +static __always_inline u64 td_tdcs_exec_read64(struct kvm_tdx *kvm_tdx, u32 field)
> +{
> + struct tdx_module_output out;
> + u64 err;
> +
> + err = tdh_mng_rd(kvm_tdx->tdr_pa, TDCS_EXEC(field), &out);
> + if (unlikely(err)) {
> + pr_err("TDH_MNG_RD[EXEC.0x%x] failed: 0x%llx\n", field, err);
> + return 0;
> + }
> + return out.r8;
> +}
> +
> #else
> struct kvm_tdx {
> struct kvm kvm;
> diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
> index af4c5bd0af1c..c0f011384934 100644
> --- a/tools/arch/x86/include/uapi/asm/kvm.h
> +++ b/tools/arch/x86/include/uapi/asm/kvm.h
> @@ -565,6 +565,7 @@ struct kvm_pmu_event_filter {
> /* Trust Domain eXtension sub-ioctl() commands. */
> enum kvm_tdx_cmd_id {
> KVM_TDX_CAPABILITIES = 0,
> + KVM_TDX_INIT_VM,
>
> KVM_TDX_CMD_NR_MAX,
> };
> @@ -610,4 +611,36 @@ struct kvm_tdx_capabilities {
> struct kvm_tdx_cpuid_config cpuid_configs[0];
> };
>
> +struct kvm_tdx_init_vm {
> + __u64 attributes;
> + __u32 max_vcpus;
> + __u32 padding;
> + __u64 mrconfigid[6]; /* sha384 digest */
> + __u64 mrowner[6]; /* sha384 digest */
> + __u64 mrownerconfig[6]; /* sha348 digest */
> + union {
> + /*
> + * KVM_TDX_INIT_VM is called before vcpu creation, thus before
> + * KVM_SET_CPUID2. CPUID configurations needs to be passed.
> + *
> + * This configuration supersedes KVM_SET_CPUID{,2}.
> + * The user space VMM, e.g. qemu, should make them consistent
> + * with this values.
> + * sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES(256)
> + * = 8KB.
> + */
> + struct {
> + struct kvm_cpuid2 cpuid;
> + /* 8KB with KVM_MAX_CPUID_ENTRIES. */
> + struct kvm_cpuid_entry2 entries[];
> + };
> + /*
> + * For future extensibility.
> + * The size(struct kvm_tdx_init_vm) = 16KB.
> + * This should be enough given sizeof(TD_PARAMS) = 1024
> + */
> + __u64 reserved[2028];
> + };
> +};
> +
> #endif /* _ASM_X86_KVM_H */
On Sun, 12 Mar 2023 10:55:48 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> The next step of TDX guest creation is to create vcpu. Allocate TDX vcpu
> structures, initialize it that doesn't require TDX SEAMCALL. TDX specific
> vcpu initialization will be implemented as independent KVM_TDX_INIT_VCPU
> so that when error occurs it's easy to determine which component has the
> issue, KVM or TDX.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> Changes v11 -> v12:
> - add more comments in tdx_vcpu_reset().
> - use KVM_BUG_ON()
>
> Changes v10 -> v11:
> - NULL check of kvmalloc_array() in tdx_vcpu_reset. Move it to
> tdx_vcpu_create()
> ---
> arch/x86/kvm/vmx/main.c | 44 ++++++++++++++++++++++++++++++----
> arch/x86/kvm/vmx/tdx.c | 49 ++++++++++++++++++++++++++++++++++++++
> arch/x86/kvm/vmx/x86_ops.h | 10 ++++++++
> arch/x86/kvm/x86.c | 2 ++
> 4 files changed, 101 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index e57b36902313..e9fd4e80b67d 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -97,6 +97,42 @@ static void vt_vm_free(struct kvm *kvm)
> tdx_vm_free(kvm);
> }
>
> +static int vt_vcpu_precreate(struct kvm *kvm)
> +{
> + if (is_td(kvm))
> + return 0;
> +
> + return vmx_vcpu_precreate(kvm);
> +}
> +
> +static int vt_vcpu_create(struct kvm_vcpu *vcpu)
> +{
> + if (is_td_vcpu(vcpu))
> + return tdx_vcpu_create(vcpu);
> +
> + return vmx_vcpu_create(vcpu);
> +}
> +
> +static void vt_vcpu_free(struct kvm_vcpu *vcpu)
> +{
> + if (is_td_vcpu(vcpu)) {
> + tdx_vcpu_free(vcpu);
> + return;
> + }
> +
> + vmx_vcpu_free(vcpu);
> +}
> +
> +static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> +{
> + if (is_td_vcpu(vcpu)) {
> + tdx_vcpu_reset(vcpu, init_event);
> + return;
> + }
> +
> + vmx_vcpu_reset(vcpu, init_event);
> +}
> +
> static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> {
> if (!is_td(kvm))
> @@ -137,10 +173,10 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .vm_destroy = vt_vm_destroy,
> .vm_free = vt_vm_free,
>
> - .vcpu_precreate = vmx_vcpu_precreate,
> - .vcpu_create = vmx_vcpu_create,
> - .vcpu_free = vmx_vcpu_free,
> - .vcpu_reset = vmx_vcpu_reset,
> + .vcpu_precreate = vt_vcpu_precreate,
> + .vcpu_create = vt_vcpu_create,
> + .vcpu_free = vt_vcpu_free,
> + .vcpu_reset = vt_vcpu_reset,
>
> .prepare_switch_to_guest = vmx_prepare_switch_to_guest,
> .vcpu_load = vmx_vcpu_load,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index aeec8bcf8921..4fec35f4f5b2 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -321,6 +321,55 @@ int tdx_vm_init(struct kvm *kvm)
> return 0;
> }
>
> +int tdx_vcpu_create(struct kvm_vcpu *vcpu)
> +{
> + /*
> + * On cpu creation, cpuid entry is blank. Forcibly enable
> + * X2APIC feature to allow X2APIC.
> + * Because vcpu_reset() can't return error, allocation is done here.
> + */
> + WARN_ON_ONCE(vcpu->arch.cpuid_entries);
> + WARN_ON_ONCE(vcpu->arch.cpuid_nent);
> +
> + /* TDX only supports x2APIC, which requires an in-kernel local APIC. */
> + if (!vcpu->arch.apic)
> + return -EINVAL;
> +
> + fpstate_set_confidential(&vcpu->arch.guest_fpu);
> +
> + vcpu->arch.efer = EFER_SCE | EFER_LME | EFER_LMA | EFER_NX;
> +
> + vcpu->arch.cr0_guest_owned_bits = -1ul;
> + vcpu->arch.cr4_guest_owned_bits = -1ul;
> +
> + vcpu->arch.tsc_offset = to_kvm_tdx(vcpu->kvm)->tsc_offset;
> + vcpu->arch.l1_tsc_offset = vcpu->arch.tsc_offset;
> + vcpu->arch.guest_state_protected =
> + !(to_kvm_tdx(vcpu->kvm)->attributes & TDX_TD_ATTRIBUTE_DEBUG);
> +
> + return 0;
> +}
> +
> +void tdx_vcpu_free(struct kvm_vcpu *vcpu)
> +{
> + /* This is stub for now. More logic will come. */
> +}
> +
> +void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> +{
> +
> + /* Ignore INIT silently because TDX doesn't support INIT event. */
> + if (init_event)
> + return;
> +
> + /* This is stub for now. More logic will come here. */
> +
> + /*
> + * Don't update mp_state to runnable because more initialization
> + * is needed by TDX_VCPU_INIT.
> + */
^
guess this comment belongs to the later patch.
> +}
> +
> int tdx_dev_ioctl(void __user *argp)
> {
> struct kvm_tdx_capabilities __user *user_caps;
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 544f99141f8f..1669c95d8249 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -149,7 +149,12 @@ int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
> int tdx_vm_init(struct kvm *kvm);
> void tdx_mmu_release_hkid(struct kvm *kvm);
> void tdx_vm_free(struct kvm *kvm);
> +
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> +
> +int tdx_vcpu_create(struct kvm_vcpu *vcpu);
> +void tdx_vcpu_free(struct kvm_vcpu *vcpu);
> +void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> static inline void tdx_hardware_unsetup(void) {}
> @@ -163,7 +168,12 @@ static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
> static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
> static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
> static inline void tdx_vm_free(struct kvm *kvm) {}
> +
> static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
> +
> +static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
> +static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
> +static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
> #endif
>
> #endif /* __KVM_X86_VMX_X86_OPS_H */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index a1d5d920302b..0ba15a9e126f 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -496,6 +496,7 @@ int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> kvm_recalculate_apic_map(vcpu->kvm);
> return 0;
> }
> +EXPORT_SYMBOL_GPL(kvm_set_apic_base);
>
> /*
> * Handle a fault on a hardware virtualization (VMX or SVM) instruction.
> @@ -12170,6 +12171,7 @@ bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
> {
> return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id;
> }
> +EXPORT_SYMBOL_GPL(kvm_vcpu_is_reset_bsp);
>
> bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
> {
On Sun, 12 Mar 2023 10:55:54 -0700
[email protected] wrote:
> From: Sean Christopherson <[email protected]>
>
> Add support to MMU caches for initializing a page with a custom 64-bit
> value, e.g. to pre-fill an entire page table with non-zero PTE values.
> The functionality will be used by x86 to support Intel's TDX, which needs
> to set bit 63 in all non-present PTEs in order to prevent !PRESENT page
> faults from getting reflected into the guest (Intel's EPT Violation #VE
> architecture made the less than brilliant decision of having the per-PTE
> behavior be opt-out instead of opt-in).
>
> Signed-off-by: Sean Christopherson <[email protected]>
Your Sighned-off-by is required as well.
> ---
> include/linux/kvm_types.h | 1 +
> virt/kvm/kvm_main.c | 16 ++++++++++++++--
> 2 files changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h
> index 2728d49bbdf6..7c2b9332b7c5 100644
> --- a/include/linux/kvm_types.h
> +++ b/include/linux/kvm_types.h
> @@ -94,6 +94,7 @@ struct kvm_mmu_memory_cache {
> int nobjs;
> gfp_t gfp_zero;
> gfp_t gfp_custom;
> + u64 init_value;
> struct kmem_cache *kmem_cache;
> int capacity;
> void **objects;
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index f8495e27d210..87400796df6e 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -381,12 +381,17 @@ static void kvm_flush_shadow_all(struct kvm *kvm)
> static inline void *mmu_memory_cache_alloc_obj(struct kvm_mmu_memory_cache *mc,
> gfp_t gfp_flags)
> {
> + void *page;
> +
> gfp_flags |= mc->gfp_zero;
>
> if (mc->kmem_cache)
> return kmem_cache_alloc(mc->kmem_cache, gfp_flags);
> - else
> - return (void *)__get_free_page(gfp_flags);
> +
> + page = (void *)__get_free_page(gfp_flags);
> + if (page && mc->init_value)
> + memset64(page, mc->init_value, PAGE_SIZE / sizeof(mc->init_value));
> + return page;
> }
>
> int __kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int capacity, int min)
> @@ -401,6 +406,13 @@ int __kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int capacity,
> if (WARN_ON_ONCE(!capacity))
> return -EIO;
>
> + /*
> + * Custom init values can be used only for page allocations,
> + * and obviously conflict with __GFP_ZERO.
> + */
> + if (WARN_ON_ONCE(mc->init_value && (mc->kmem_cache || mc->gfp_zero)))
> + return -EIO;
> +
> mc->objects = kvmalloc_array(sizeof(void *), capacity, gfp);
> if (!mc->objects)
> return -ENOMEM;
On Mon, Apr 03, 2023 at 05:28:35PM +0300,
Zhi Wang <[email protected]> wrote:
> On Mon, 3 Apr 2023 11:46:15 +0800
> Xiaoyao Li <[email protected]> wrote:
>
> > On 3/31/2023 8:44 PM, Zhi Wang wrote:
> > > On Thu, 30 Mar 2023 17:18:03 -0700
> > > Isaku Yamahata <[email protected]> wrote:
> > >
> > >> On Wed, Mar 29, 2023 at 04:17:22PM -0700,
> > >> Isaku Yamahata <[email protected]> wrote:
> > >>
> > >>> On Sat, Mar 25, 2023 at 10:43:06AM +0200,
> > >>> Zhi Wang <[email protected]> wrote:
> > >>>
> > >>>> On Sun, 12 Mar 2023 10:55:40 -0700
> > >>>> [email protected] wrote:
> > >>>>
> > >>>> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> > >>>> does not use it at all and all the system-scoped ioctl of SNP going through
> > >>>> the CCP driver. So getting system-scope information of TDX/SNP will end up
> > >>>> differently.
> > >>>>
> > >>>> Any thought, Sean? Moving getting SNP system-wide information to
> > >>>> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> > >>>> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
> > >>>
> > >>> We only need global parameters of the TDX module, and we don't interact with TDX
> > >>> module at this point. One alternative is to export those parameters via sysfs.
> > >>> Also the existence of the sysfs node indicates that the TDX module is
> > >>> loaded(initialized?) or not in addition to boot log. Thus we can drop system
> > >>> scope one.
> > >>> What do you think?
> > >>>
> > >
> > > I like this idea and the patch below, it feels right for me now. It would be nice
> > > if more folks can chime in and comment.
> >
> > SYSFS option requires CONFIG_SYSFS, which reqiures CONFIG_KVM_TDX to
> > select CONFIG_SYSFS.
> >
> > >>> Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
> > >>> KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
> > >>> I don't think it can be split out to independent driver.
> > >>
> > >
> > > They can stay in KVM as they are KVM-specific. SNP also has KVM-specific ioctls
> > > which wraps the SEV driver calls. At this level, both TDX and SNP go their specific
> > > implementation without more abstraction other than KVM_ENCRYPT_MEMORY_OP. Their
> > > strategies are aligned.
> > >
> > > The problem of the previous approach was the abstraction that no other implementation
> > > is using it. It is like, TDX wants a higher abstraction to cover both TDX and SNP,
> > > but SNP is not using it, which makes the abstraction looks strange.
> >
> > Note, before this TDX enabling series, KVM_MEMORY_ENCRYPT_OP is a VM
> > scope ioctl, that only serves for SEV and no other implementation uses
> > it. I see no reason why cannot introduce a new IOCTL in x86 KVM that
> > serves only one vendor.
> >
>
> My point is: time is different. When KVM_MEMORY_ENCRYPT_OP is there,
> there was *only* one vendor and SEV/SNP didn't know how the future vendor
> is going to use the ioctl. That is a reasonable case an generic ioctl can
> have one vendor to back up.
>
> The background here is: now another vendor is coming and there are going to
> be two vendors. The two vendors' flows are much clearer than early stage.
> Like, they know which flow is going to be used by each other.
>
> With these kept in mind, IMHO, it is not appropriate to introduce
> an generic ioctl that only one vendor is going to use, meanwhile
> we have already known another vendor is not going to use it.
>
> Defining a new userspace ABI is a serious thing and it is not an early
> stage anymore. Actually I think it is the best time to see how the
> code infrastructure should be re-purposed at this time.
>
> > We choose KVM_MEMORY_ENCRYPT_OP for TDX platform scope, just because we
> > reuse KVM_MEMORY_ENCRYPT_OP for TDX VM-scope and extend it to TDX vcpu
> > scope. It's just to avoid defining a new IOCTL number.
> >
> > We can rename it to KVM_GET_CC_CAPABILITIES, and even return different
> > capabilities based on VM type. And even, if SNP wants to use it, I think
> > it can wrap SNP driver calls inside this IOCTL?
> >
>
> I am not opposed to this option as it shows effort to improve it and it
> is constructive. But this needs to be figured out with AMD folks and
> maintainers. E.g. what should be the best CC ioctl scheme for KVM?
> vendor-specific or generic, which brings better benefit for the userspace,
> and less maintenance burden.
>
> Back to the reason why I think a vendor-specific sysinfo interface for TDX
> is necessary:
>
> 1) SEV driver has been there for quite some time. Unless people thinks an
> generic CC ioctl scheme is a way to go, then there will be motivation and
> efforts putting on it. The efforts is not only about wrapping SEV ioctls,
> it needs a systematic spec of generic CC ioctl scheme.
>
> 2) TDX doesn't have a driver like SEV and possibly not going to have one in
> the future. For those non-KVM related control flow of TDX in future, they
> can re-use this and stay away from KVM interface. (If vendor-specific
> scheme is the future direction.)
>
> > kvm.ko is special that it needs to serve two vendors. Sometime it's
> > unaviodable that an interface is only used by one vendor.
>
> I am afraid that in this case it is avoidable right?
We can make KVM_TDX_CAPABILITIES vm-scoped one so that devoce-scoped
KVM_EMORY_ENCRYPT_OP isn't needed. At least qemu is fine.
Do you think vm-scoped KVM_TDX_CAPABILITIES is fine?
--
Isaku Yamahata <[email protected]>
On Sun, Apr 02, 2023 at 11:41:58AM +0300,
Zhi Wang <[email protected]> wrote:
> > > > +void tdx_mmu_release_hkid(struct kvm *kvm)
> > > > +{
> > > > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > > > + cpumask_var_t packages;
> > > > + bool cpumask_allocated;
> > > > + u64 err;
> > > > + int ret;
> > > > + int i;
> > > > +
> > > > + if (!is_hkid_assigned(kvm_tdx))
> > > > + return;
> > > > +
> > > > + if (!is_td_created(kvm_tdx))
> > > > + goto free_hkid;
> > > > +
> > > > + cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
> > > > + cpus_read_lock();
> > > > + for_each_online_cpu(i) {
> > > > + if (cpumask_allocated &&
> > > > + cpumask_test_and_set_cpu(topology_physical_package_id(i),
> > > > + packages))
> > > > + continue;
> > >
> > > Is this necessary to check cpumask_allocated in the while loop? if cpumask
> > > is not succefully allocated, wouldn't it be better to bail out just after
> > > it?
> >
> > No because we can't return error here. It's better to do in-efficiently freeing
> > resources instead of leak.
> >
> > We can move the check out of loop. But it would be ugly
> > (if () {cpu loop} else {cpu loop} ) and this function isn't performance
> > critical. Also I think it's okay to depend on compiler optimization for loop
> > invariant. My compiler didn't optimize it in this case, though.
> >
>
> Do you mean the tdh_mng_key_freeid() is still required if failing to allocate
> the cpumask var and do TDH.PHYMEM_CACHE_WB(WBINVD) on each CPU?
>
> Out of curiosity, I took a look on the TDX module source code [1], it seems TDX
> module has an additional check in TDH.MNG.KEY.FREEID. TDH.MNG.VPFLUSHDONE [2]
> will mark the pending wbinvd in a bitmap:
>
> ...
> /**
> * Create the WBINVD_BITMAP per-package.
> * Set to 1 num_of_pkgs bits from the LSB
> */
> global_data_ptr->kot.entries[curr_hkid].wbinvd_bitmap = global_data_ptr->pkg_config_bitmap; /* <----HERE */
>
> // Set new TD life cycle state
> tdr_ptr->management_fields.lifecycle_state = TD_BLOCKED;
>
> // Set the proper new KOT entry state
> global_data_ptr->kot.entries[curr_hkid].state = (uint8_t)KOT_STATE_HKID_FLUSHED;
> ...
>
> And TDH.MNG.KEY.FREEID [3] will check if the pending WBINVD has been performed:
>
> ...
> /**
> * If TDH_PHYMEM_CACHE_WB was executed on all packages/cores,
> * set the KOT entry, set the KOT entry state to HKID_FREE.
> */
> curr_hkid = tdr_ptr->key_management_fields.hkid;
> tdx_debug_assert(global_data_ptr->kot.entr/ies[curr_hkid].state == KOT_STATE_HKID_FLUSHED);
> if (global_data_ptr->kot.entries[curr_hkid].wbinvd_bitmap != 0) /* HERE */
> {
> TDX_ERROR("CACHEWB is not complete for this HKID (=%x)\n", curr_hkid);
> return_val = TDX_WBCACHE_NOT_COMPLETE;
> goto EXIT;
> }
> ...
>
> Guess the conclusion is: if TDH.PHYMEM.CACHE.WB is not performed on each
> required CPU correctly, TDH.MNG.KEY.FREEID will fail as well. A leak seems
> the only option (none of us likes a leak, but...).
Why do we need to leak key? If we fails to allocate cpumask, we can issue
TDH.PHYMEM.CACHE.WB on all pCPUs instead of all packages.
If we call TDH.PHYMEM.CACHE.WB multiple times on the same package, it may return
error. It's benign. It is suboptimal, but it's much better than leaking hkid.
--
Isaku Yamahata <[email protected]>
On Tue, Apr 04, 2023 at 10:23:35PM +0300,
Zhi Wang <[email protected]> wrote:
> On Sun, 12 Mar 2023 10:55:44 -0700
> [email protected] wrote:
>
> > From: Isaku Yamahata <[email protected]>
> >
> > TDX requires additional parameters for TDX VM for confidential execution to
> > protect its confidentiality of its memory contents and its CPU state from
> > any other software, including VMM. When creating guest TD VM before
> > creating vcpu, the number of vcpu, TSC frequency (that is same among
> > vcpus. and it can't be changed.) CPUIDs which is emulated by the TDX
> ^ This sentence seems broken. "
Here is the revised one.
TDX requires additional parameters for TDX VM for confidential execution to
protect the confidentiality of its memory contents and CPU state from any
other software, including VMM. When creating a guest TD VM before creating
vcpu, the number of vcpu, TSC frequency (the values are the same among
vcpus, and it can't change.) CPUIDs which the TDX module emulates. Guest
TDs can trust those CPUIDs and sha384 values for measurement.
Add a new subcommand, KVM_TDX_INIT_VM, to pass parameters for the TDX
guest. It assigns an encryption key to the TDX guest for memory
encryption. TDX encrypts memory per guest basis. The device model, say
qemu, passes per-VM parameters for the TDX guest. The maximum number of
vcpus, TSC frequency (TDX guest has fixed VM-wide TSC frequency, not per
vcpu. The TDX guest can not change it.), attributes (production or debug),
available extended features (which configure guest XCR0, IA32_XSS MSR),
CPUIDs, sha384 measurements, etc.
Call this subcommand before creating vcpu and KVM_SET_CPUID2, i.e. CPUID
configurations aren't available yet. So CPUIDs configuration values need
to be passed in struct kvm_tdx_init_vm. The device model's responsibility
to make this CPUID config for KVM_TDX_INIT_VM and KVM_SET_CPUID2.
> > diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
> > index af4c5bd0af1c..68e8d544afe5 100644
> > --- a/arch/x86/include/uapi/asm/kvm.h
> > +++ b/arch/x86/include/uapi/asm/kvm.h
> > @@ -565,6 +565,7 @@ struct kvm_pmu_event_filter {
> > /* Trust Domain eXtension sub-ioctl() commands. */
> > enum kvm_tdx_cmd_id {
> > KVM_TDX_CAPABILITIES = 0,
> > + KVM_TDX_INIT_VM,
> >
> > KVM_TDX_CMD_NR_MAX,
> > };
> > @@ -610,4 +611,27 @@ struct kvm_tdx_capabilities {
> > struct kvm_tdx_cpuid_config cpuid_configs[0];
> > };
> >
> > +struct kvm_tdx_init_vm {
> > + __u64 attributes;
> > + __u64 mrconfigid[6]; /* sha384 digest */
> > + __u64 mrowner[6]; /* sha384 digest */
> > + __u64 mrownerconfig[6]; /* sha348 digest */
> > + /*
> > + * For future extensibility to make sizeof(struct kvm_tdx_init_vm) = 8KB.
> > + * This should be enough given sizeof(TD_PARAMS) = 1024.
> > + * 8KB was chosen given because
> > + * sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES(=256) = 8KB.
> > + */
> > + __u64 reserved[1004];
> > +
> > + /*
> > + * KVM_TDX_INIT_VM is called before vcpu creation, thus before
> > + * KVM_SET_CPUID2.
> > + * This configuration supersedes KVM_SET_CPUID2s for VCPUs. The user
> > + * space VMM, e.g. qemu, should make KVM_SET_CPUID2 consistent with this
> > + * values.
> ^
> It would be nice to have one more sentence to talk about the
> consequence if QEMU configures different CPUIDs in KVM_TDX_INIT_VM and the later
> SET_CPUID2.
Here is the updated one.
/*
* Call KVM_TDX_INIT_VM before vcpu creation, thus before
* KVM_SET_CPUID2.
* This configuration supersedes KVM_SET_CPUID2s for VCPUs because the
* TDX module directly virtualizes those CPUIDs without VMM. The user
* space VMM, e.g. qemu, should make KVM_SET_CPUID2 consistent with
* those values. If it doesn't, KVM may have wrong idea of vCPUIDs of
* the guest, and KVM may wrongly emulate CPUIDs or MSRs that the TDX
* module doesn't virtualize.
*/
--
Isaku Yamahata <[email protected]>
On Tue, Apr 04, 2023 at 10:44:38PM +0300,
Zhi Wang <[email protected]> wrote:
> > +void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> > +{
> > +
> > + /* Ignore INIT silently because TDX doesn't support INIT event. */
> > + if (init_event)
> > + return;
> > +
> > + /* This is stub for now. More logic will come here. */
> > +
> > + /*
> > + * Don't update mp_state to runnable because more initialization
> > + * is needed by TDX_VCPU_INIT.
> > + */
> ^
> guess this comment belongs to the later patch.
Ah, right. I'll move the comment to the next patch.
--
Isaku Yamahata <[email protected]>
On Wed, Mar 29, 2023 at 06:04:38PM -0700,
Isaku Yamahata <[email protected]> wrote:
> On Wed, Mar 29, 2023 at 11:17:31PM +0000,
> "Huang, Kai" <[email protected]> wrote:
>
> > On Wed, 2023-03-29 at 14:56 -0700, Isaku Yamahata wrote:
> > > On Wed, Mar 29, 2023 at 01:13:45AM +0000,
> > > "Huang, Kai" <[email protected]> wrote:
> > >
> > > > >
> > > > > > >
> > > > > > > + /*
> > > > > > > + * TDX requires those methods to enable VMXON by
> > > > > > > + * kvm_hardware_enable/disable_all()
> > > > > > > + */
> > > > > > > + static_call_update(kvm_x86_check_processor_compatibility,
> > > > > > > + ops->runtime_ops->check_processor_compatibility);
> > > > > > > + static_call_update(kvm_x86_hardware_enable,
> > > > > > > + ops->runtime_ops->hardware_enable);
> > > > > > > + static_call_update(kvm_x86_hardware_disable,
> > > > > > > + ops->runtime_ops->hardware_disable);
> > > > > > > r = ops->hardware_setup();
> > > > > > > if (r != 0)
> > > > > > > goto out_mmu_exit;
> > > > > >
> > > > > > Hmm.. I think this is ugly. Perhaps we should never do any
> > > > > > static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> > > > > > called before kvm_ops_update() and may update vendor's kvm_x86_ops.
> > > > > >
> > > > > > So probably use hardware_enable_all() in hardware_setup() is a bad idea.
> > > > > >
> > > > > > I think we have below options on how to handle:
> > > > > >
> > > > > > 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> > > > > > something like below:
> > > > > >
> > > > > > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > > > > > {
> > > > > > ...
> > > > > >
> > > > > > cpus_read_lock();
> > > > > > r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> > > > > > if (!r)
> > > > > > r = tdx_module_setup();
> > > > > > on_each_cpu(vt_x86_ops.hardware_disable, ...);
> > > > > > cpus_read_unlock();
> > > > > >
> > > > > > ...
> > > > > > }
> > > > > >
> > > > > > But this doesn't clean up nicely when there's some particular cpus fail to do
> > > > > > hardware_enable(). To clean up nicely, we do need additional things similar to
> > > > > > the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> > > > > > wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> > > > > > hardware_enable() successfully.
> > > > > >
> > > > > > 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> > > > > > code self-contained. But this would require exposing kvm_x86_ops as symbol,
> > > > > > which isn't nice either.
> > > > > >
> > > > > > 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> > > > > > after kvm_ops_update().
> > > > > >
> > > > > > Personally, I think 3) perhaps is the most elegant one, but not sure whether
> > > > > > Sean/Paolo has any opinion.
> > > > >
> > > > > I think we can simply update the ops before calling hardware_enable() and
> > > > > clean up ops on failure.
> > > > >
> > > > >
> > > >
> > > > This doesn't work because hardware_setup() may update vendor's kvm_x86_ops.
> > > >
> > > > If you do kvm_ops_update() before hardware_setup(), you need to manually update
> > > > those updated (in hardware_setup()) callbacks again after.
> > >
> > > We can call kvm_ops_update() twice before and after hardware_setup().
> > >
> >
> > Personally I think it's too ugly.
>
> So you prefer the option 3 to calling kvm_ops_update() twice. Okay, I'll update
> the patch.
After playing with hardware_post_setup(), it's inevitable to call
kvm_ops_update() twice.
When VMX initialization succeeded with hardware_setup(), but TDX initialization
with hardware_post_setup() failed, we'd like to support only VMX with warning
message. In such case, we need to revert x86_ops to VMX only.
It doesn't make sense to introduce hardware_post_setup() to avoid calling
kvm_update_ops twice.
--
Isaku Yamahata <[email protected]>
On Wed, 2023-04-05 at 13:07 -0700, Isaku Yamahata wrote:
> On Wed, Mar 29, 2023 at 06:04:38PM -0700,
> Isaku Yamahata <[email protected]> wrote:
>
> > On Wed, Mar 29, 2023 at 11:17:31PM +0000,
> > "Huang, Kai" <[email protected]> wrote:
> >
> > > On Wed, 2023-03-29 at 14:56 -0700, Isaku Yamahata wrote:
> > > > On Wed, Mar 29, 2023 at 01:13:45AM +0000,
> > > > "Huang, Kai" <[email protected]> wrote:
> > > >
> > > > > >
> > > > > > > >
> > > > > > > > + /*
> > > > > > > > + * TDX requires those methods to enable VMXON by
> > > > > > > > + * kvm_hardware_enable/disable_all()
> > > > > > > > + */
> > > > > > > > + static_call_update(kvm_x86_check_processor_compatibility,
> > > > > > > > + ops->runtime_ops->check_processor_compatibility);
> > > > > > > > + static_call_update(kvm_x86_hardware_enable,
> > > > > > > > + ops->runtime_ops->hardware_enable);
> > > > > > > > + static_call_update(kvm_x86_hardware_disable,
> > > > > > > > + ops->runtime_ops->hardware_disable);
> > > > > > > > r = ops->hardware_setup();
> > > > > > > > if (r != 0)
> > > > > > > > goto out_mmu_exit;
> > > > > > >
> > > > > > > Hmm.. I think this is ugly. Perhaps we should never do any
> > > > > > > static_call(kvm_x86_xxx)() in hardware_setup(), because hardware_setup() is
> > > > > > > called before kvm_ops_update() and may update vendor's kvm_x86_ops.
> > > > > > >
> > > > > > > So probably use hardware_enable_all() in hardware_setup() is a bad idea.
> > > > > > >
> > > > > > > I think we have below options on how to handle:
> > > > > > >
> > > > > > > 1) Use VMX's kvm_x86_ops directly in tdx_hardware_setup(). For instance,
> > > > > > > something like below:
> > > > > > >
> > > > > > > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
> > > > > > > {
> > > > > > > ...
> > > > > > >
> > > > > > > cpus_read_lock();
> > > > > > > r = on_each_cpu(vt_x86_ops.hardware_enable, ...);
> > > > > > > if (!r)
> > > > > > > r = tdx_module_setup();
> > > > > > > on_each_cpu(vt_x86_ops.hardware_disable, ...);
> > > > > > > cpus_read_unlock();
> > > > > > >
> > > > > > > ...
> > > > > > > }
> > > > > > >
> > > > > > > But this doesn't clean up nicely when there's some particular cpus fail to do
> > > > > > > hardware_enable(). To clean up nicely, we do need additional things similar to
> > > > > > > the hardware_enable_all() code path: a per-cpu variable or a cpumask_t + a
> > > > > > > wrapper of vt_x86_ops->hardware_enable() to track which cpus have done
> > > > > > > hardware_enable() successfully.
> > > > > > >
> > > > > > > 2) Move those static_call_update() into tdx_hardware_setup() so they are TDX
> > > > > > > code self-contained. But this would require exposing kvm_x86_ops as symbol,
> > > > > > > which isn't nice either.
> > > > > > >
> > > > > > > 3) Introduce another kvm_x86_init_ops->hardware_post_setup(), which is called
> > > > > > > after kvm_ops_update().
> > > > > > >
> > > > > > > Personally, I think 3) perhaps is the most elegant one, but not sure whether
> > > > > > > Sean/Paolo has any opinion.
> > > > > >
> > > > > > I think we can simply update the ops before calling hardware_enable() and
> > > > > > clean up ops on failure.
> > > > > >
> > > > > >
> > > > >
> > > > > This doesn't work because hardware_setup() may update vendor's kvm_x86_ops.
> > > > >
> > > > > If you do kvm_ops_update() before hardware_setup(), you need to manually update
> > > > > those updated (in hardware_setup()) callbacks again after.
> > > >
> > > > We can call kvm_ops_update() twice before and after hardware_setup().
> > > >
> > >
> > > Personally I think it's too ugly.
> >
> > So you prefer the option 3 to calling kvm_ops_update() twice. Okay, I'll update
> > the patch.
>
> After playing with hardware_post_setup(), it's inevitable to call
> kvm_ops_update() twice.
> When VMX initialization succeeded with hardware_setup(), but TDX initialization
> with hardware_post_setup() failed, we'd like to support only VMX with warning
> message. In such case, we need to revert x86_ops to VMX only.
> It doesn't make sense to introduce hardware_post_setup() to avoid calling
> kvm_update_ops twice.
>
OK. Then how about option 1) ?
We just need another wrapper around vt_x86_ops.hardware_{enable|disable}() and
use a VT's own per-cpu variable to track which has cpu has done the
vmx_hardware_enable().
We can even put the per-cpu variable inside the vt_hardware_enable() itself w/o
introducing the wrapper.
But again it's better if Sean can input here.
On Wed, 5 Apr 2023 11:16:18 -0700
Isaku Yamahata <[email protected]> wrote:
> On Sun, Apr 02, 2023 at 11:41:58AM +0300,
> Zhi Wang <[email protected]> wrote:
>
> > > > > +void tdx_mmu_release_hkid(struct kvm *kvm)
> > > > > +{
> > > > > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > > > > + cpumask_var_t packages;
> > > > > + bool cpumask_allocated;
> > > > > + u64 err;
> > > > > + int ret;
> > > > > + int i;
> > > > > +
> > > > > + if (!is_hkid_assigned(kvm_tdx))
> > > > > + return;
> > > > > +
> > > > > + if (!is_td_created(kvm_tdx))
> > > > > + goto free_hkid;
> > > > > +
> > > > > + cpumask_allocated = zalloc_cpumask_var(&packages, GFP_KERNEL);
> > > > > + cpus_read_lock();
> > > > > + for_each_online_cpu(i) {
> > > > > + if (cpumask_allocated &&
> > > > > + cpumask_test_and_set_cpu(topology_physical_package_id(i),
> > > > > + packages))
> > > > > + continue;
> > > >
> > > > Is this necessary to check cpumask_allocated in the while loop? if cpumask
> > > > is not succefully allocated, wouldn't it be better to bail out just after
> > > > it?
> > >
> > > No because we can't return error here. It's better to do in-efficiently freeing
> > > resources instead of leak.
> > >
> > > We can move the check out of loop. But it would be ugly
> > > (if () {cpu loop} else {cpu loop} ) and this function isn't performance
> > > critical. Also I think it's okay to depend on compiler optimization for loop
> > > invariant. My compiler didn't optimize it in this case, though.
> > >
> >
> > Do you mean the tdh_mng_key_freeid() is still required if failing to allocate
> > the cpumask var and do TDH.PHYMEM_CACHE_WB(WBINVD) on each CPU?
>
> >
> > Out of curiosity, I took a look on the TDX module source code [1], it seems TDX
> > module has an additional check in TDH.MNG.KEY.FREEID. TDH.MNG.VPFLUSHDONE [2]
> > will mark the pending wbinvd in a bitmap:
> >
> > ...
> > /**
> > * Create the WBINVD_BITMAP per-package.
> > * Set to 1 num_of_pkgs bits from the LSB
> > */
> > global_data_ptr->kot.entries[curr_hkid].wbinvd_bitmap = global_data_ptr->pkg_config_bitmap; /* <----HERE */
> >
> > // Set new TD life cycle state
> > tdr_ptr->management_fields.lifecycle_state = TD_BLOCKED;
> >
> > // Set the proper new KOT entry state
> > global_data_ptr->kot.entries[curr_hkid].state = (uint8_t)KOT_STATE_HKID_FLUSHED;
> > ...
> >
> > And TDH.MNG.KEY.FREEID [3] will check if the pending WBINVD has been performed:
> >
> > ...
> > /**
> > * If TDH_PHYMEM_CACHE_WB was executed on all packages/cores,
> > * set the KOT entry, set the KOT entry state to HKID_FREE.
> > */
> > curr_hkid = tdr_ptr->key_management_fields.hkid;
> > tdx_debug_assert(global_data_ptr->kot.entr/ies[curr_hkid].state == KOT_STATE_HKID_FLUSHED);
> > if (global_data_ptr->kot.entries[curr_hkid].wbinvd_bitmap != 0) /* HERE */
> > {
> > TDX_ERROR("CACHEWB is not complete for this HKID (=%x)\n", curr_hkid);
> > return_val = TDX_WBCACHE_NOT_COMPLETE;
> > goto EXIT;
> > }
> > ...
> >
> > Guess the conclusion is: if TDH.PHYMEM.CACHE.WB is not performed on each
> > required CPU correctly, TDH.MNG.KEY.FREEID will fail as well. A leak seems
> > the only option (none of us likes a leak, but...).
>
> Why do we need to leak key? If we fails to allocate cpumask, we can issue
> TDH.PHYMEM.CACHE.WB on all pCPUs instead of all packages.
> If we call TDH.PHYMEM.CACHE.WB multiple times on the same package, it may return
> error. It's benign. It is suboptimal, but it's much better than leaking hkid.
I guess I misunderstood the following sentence in the previous email. Now I
get it. It is a combination of failure-resolving and normal-resolving.
> > We can move the check out of loop. But it would be ugly
> > (if () {cpu loop} else {cpu loop} ) and this function isn't performance
> > critical.
On Wed, 5 Apr 2023 11:07:20 -0700
Isaku Yamahata <[email protected]> wrote:
> On Mon, Apr 03, 2023 at 05:28:35PM +0300,
> Zhi Wang <[email protected]> wrote:
>
> > On Mon, 3 Apr 2023 11:46:15 +0800
> > Xiaoyao Li <[email protected]> wrote:
> >
> > > On 3/31/2023 8:44 PM, Zhi Wang wrote:
> > > > On Thu, 30 Mar 2023 17:18:03 -0700
> > > > Isaku Yamahata <[email protected]> wrote:
> > > >
> > > >> On Wed, Mar 29, 2023 at 04:17:22PM -0700,
> > > >> Isaku Yamahata <[email protected]> wrote:
> > > >>
> > > >>> On Sat, Mar 25, 2023 at 10:43:06AM +0200,
> > > >>> Zhi Wang <[email protected]> wrote:
> > > >>>
> > > >>>> On Sun, 12 Mar 2023 10:55:40 -0700
> > > >>>> [email protected] wrote:
> > > >>>>
> > > >>>> Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> > > >>>> does not use it at all and all the system-scoped ioctl of SNP going through
> > > >>>> the CCP driver. So getting system-scope information of TDX/SNP will end up
> > > >>>> differently.
> > > >>>>
> > > >>>> Any thought, Sean? Moving getting SNP system-wide information to
> > > >>>> KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> > > >>>> CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
> > > >>>
> > > >>> We only need global parameters of the TDX module, and we don't interact with TDX
> > > >>> module at this point. One alternative is to export those parameters via sysfs.
> > > >>> Also the existence of the sysfs node indicates that the TDX module is
> > > >>> loaded(initialized?) or not in addition to boot log. Thus we can drop system
> > > >>> scope one.
> > > >>> What do you think?
> > > >>>
> > > >
> > > > I like this idea and the patch below, it feels right for me now. It would be nice
> > > > if more folks can chime in and comment.
> > >
> > > SYSFS option requires CONFIG_SYSFS, which reqiures CONFIG_KVM_TDX to
> > > select CONFIG_SYSFS.
> > >
> > > >>> Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
> > > >>> KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
> > > >>> I don't think it can be split out to independent driver.
> > > >>
> > > >
> > > > They can stay in KVM as they are KVM-specific. SNP also has KVM-specific ioctls
> > > > which wraps the SEV driver calls. At this level, both TDX and SNP go their specific
> > > > implementation without more abstraction other than KVM_ENCRYPT_MEMORY_OP. Their
> > > > strategies are aligned.
> > > >
> > > > The problem of the previous approach was the abstraction that no other implementation
> > > > is using it. It is like, TDX wants a higher abstraction to cover both TDX and SNP,
> > > > but SNP is not using it, which makes the abstraction looks strange.
> > >
> > > Note, before this TDX enabling series, KVM_MEMORY_ENCRYPT_OP is a VM
> > > scope ioctl, that only serves for SEV and no other implementation uses
> > > it. I see no reason why cannot introduce a new IOCTL in x86 KVM that
> > > serves only one vendor.
> > >
> >
> > My point is: time is different. When KVM_MEMORY_ENCRYPT_OP is there,
> > there was *only* one vendor and SEV/SNP didn't know how the future vendor
> > is going to use the ioctl. That is a reasonable case an generic ioctl can
> > have one vendor to back up.
> >
> > The background here is: now another vendor is coming and there are going to
> > be two vendors. The two vendors' flows are much clearer than early stage.
> > Like, they know which flow is going to be used by each other.
> >
> > With these kept in mind, IMHO, it is not appropriate to introduce
> > an generic ioctl that only one vendor is going to use, meanwhile
> > we have already known another vendor is not going to use it.
> >
> > Defining a new userspace ABI is a serious thing and it is not an early
> > stage anymore. Actually I think it is the best time to see how the
> > code infrastructure should be re-purposed at this time.
> >
> > > We choose KVM_MEMORY_ENCRYPT_OP for TDX platform scope, just because we
> > > reuse KVM_MEMORY_ENCRYPT_OP for TDX VM-scope and extend it to TDX vcpu
> > > scope. It's just to avoid defining a new IOCTL number.
> > >
> > > We can rename it to KVM_GET_CC_CAPABILITIES, and even return different
> > > capabilities based on VM type. And even, if SNP wants to use it, I think
> > > it can wrap SNP driver calls inside this IOCTL?
> > >
> >
> > I am not opposed to this option as it shows effort to improve it and it
> > is constructive. But this needs to be figured out with AMD folks and
> > maintainers. E.g. what should be the best CC ioctl scheme for KVM?
> > vendor-specific or generic, which brings better benefit for the userspace,
> > and less maintenance burden.
> >
> > Back to the reason why I think a vendor-specific sysinfo interface for TDX
> > is necessary:
> >
> > 1) SEV driver has been there for quite some time. Unless people thinks an
> > generic CC ioctl scheme is a way to go, then there will be motivation and
> > efforts putting on it. The efforts is not only about wrapping SEV ioctls,
> > it needs a systematic spec of generic CC ioctl scheme.
> >
> > 2) TDX doesn't have a driver like SEV and possibly not going to have one in
> > the future. For those non-KVM related control flow of TDX in future, they
> > can re-use this and stay away from KVM interface. (If vendor-specific
> > scheme is the future direction.)
> >
> > > kvm.ko is special that it needs to serve two vendors. Sometime it's
> > > unaviodable that an interface is only used by one vendor.
> >
> > I am afraid that in this case it is avoidable right?
>
> We can make KVM_TDX_CAPABILITIES vm-scoped one so that devoce-scoped
> KVM_EMORY_ENCRYPT_OP isn't needed. At least qemu is fine.
>
> Do you think vm-scoped KVM_TDX_CAPABILITIES is fine?
That looks better to me as it will stay with other KVM_TDX* ioctls then.
On Sun, 12 Mar 2023 10:56:28 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> This patch implements running TDX vcpu. Once vcpu runs on the logical
> processor (LP), the TDX vcpu is associated with it. When the TDX vcpu
> moves to another LP, the TDX vcpu needs to flush its status on the LP.
> When destroying TDX vcpu, it needs to complete flush and flush cpu memory
> cache. Track which LP the TDX vcpu run and flush it as necessary.
>
> Do nothing on sched_in event as TDX doesn't support pause loop.
>
> TDX vcpu execution requires restoring PMU debug store after returning back
> to KVM because the TDX module unconditionally resets the value. To reuse
> the existing code, export perf_restore_debug_store.
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/kvm/vmx/main.c | 21 +++++++++++++++++++--
> arch/x86/kvm/vmx/tdx.c | 32 ++++++++++++++++++++++++++++++++
> arch/x86/kvm/vmx/tdx.h | 33 +++++++++++++++++++++++++++++++++
> arch/x86/kvm/vmx/x86_ops.h | 2 ++
> arch/x86/kvm/x86.c | 1 +
> 5 files changed, 87 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 55001b34e1f0..2fd6c954590d 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -170,6 +170,23 @@ static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> vmx_vcpu_reset(vcpu, init_event);
> }
>
> +static int vt_vcpu_pre_run(struct kvm_vcpu *vcpu)
> +{
> + if (is_td_vcpu(vcpu))
> + /* Unconditionally continue to vcpu_run(). */
> + return 1;
> +
> + return vmx_vcpu_pre_run(vcpu);
> +}
> +
> +static fastpath_t vt_vcpu_run(struct kvm_vcpu *vcpu)
> +{
> + if (is_td_vcpu(vcpu))
> + return tdx_vcpu_run(vcpu);
> +
> + return vmx_vcpu_run(vcpu);
> +}
> +
> static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
> {
> if (is_td_vcpu(vcpu)) {
> @@ -323,8 +340,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> .flush_tlb_gva = vt_flush_tlb_gva,
> .flush_tlb_guest = vt_flush_tlb_guest,
>
> - .vcpu_pre_run = vmx_vcpu_pre_run,
> - .vcpu_run = vmx_vcpu_run,
> + .vcpu_pre_run = vt_vcpu_pre_run,
> + .vcpu_run = vt_vcpu_run,
> .handle_exit = vmx_handle_exit,
> .skip_emulated_instruction = vmx_skip_emulated_instruction,
> .update_emulated_instruction = vmx_update_emulated_instruction,
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index d5a2f769a58d..28a19b14cbbc 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -11,6 +11,9 @@
> #include "x86.h"
> #include "mmu.h"
>
> +#include <trace/events/kvm.h>
> +#include "trace.h"
> +
> #undef pr_fmt
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> @@ -439,6 +442,35 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> */
> }
>
> +u64 __tdx_vcpu_run(hpa_t tdvpr, void *regs, u32 regs_mask);
> +
> +static noinstr void tdx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
> + struct vcpu_tdx *tdx)
> +{
> + guest_enter_irqoff();
> + tdx->exit_reason.full = __tdx_vcpu_run(tdx->tdvpr_pa, vcpu->arch.regs, 0);
> + guest_exit_irqoff();
> +}
> +
> +fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
> +{
> + struct vcpu_tdx *tdx = to_tdx(vcpu);
> +
> + if (unlikely(vcpu->kvm->vm_bugged)) {
> + tdx->exit_reason.full = TDX_NON_RECOVERABLE_VCPU;
> + return EXIT_FASTPATH_NONE;
> + }
> +
Maybe check if a TD vCPU is initialized here or in the vcpu_pre_run? Bascially
I am thinking what if a TD vCPU is not initialized by KVM_TDX_INIT_VCPU (TDVPR
does not even exist) and now userspace wants to run it. What would be the
consequence?
> + trace_kvm_entry(vcpu);
> +
> + tdx_vcpu_enter_exit(vcpu, tdx);
> +
> + vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET;
> + trace_kvm_exit(vcpu, KVM_ISA_VMX);
> +
> + return EXIT_FASTPATH_NONE;
> +}
> +
> void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level)
> {
> td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa & PAGE_MASK);
> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
> index 9d8445324841..af29e1d89657 100644
> --- a/arch/x86/kvm/vmx/tdx.h
> +++ b/arch/x86/kvm/vmx/tdx.h
> @@ -25,12 +25,45 @@ struct kvm_tdx {
> u64 tsc_offset;
> };
>
> +union tdx_exit_reason {
> + struct {
> + /* 31:0 mirror the VMX Exit Reason format */
> + u64 basic : 16;
> + u64 reserved16 : 1;
> + u64 reserved17 : 1;
> + u64 reserved18 : 1;
> + u64 reserved19 : 1;
> + u64 reserved20 : 1;
> + u64 reserved21 : 1;
> + u64 reserved22 : 1;
> + u64 reserved23 : 1;
> + u64 reserved24 : 1;
> + u64 reserved25 : 1;
> + u64 bus_lock_detected : 1;
> + u64 enclave_mode : 1;
> + u64 smi_pending_mtf : 1;
> + u64 smi_from_vmx_root : 1;
> + u64 reserved30 : 1;
> + u64 failed_vmentry : 1;
> +
> + /* 63:32 are TDX specific */
> + u64 details_l1 : 8;
> + u64 class : 8;
> + u64 reserved61_48 : 14;
> + u64 non_recoverable : 1;
> + u64 error : 1;
> + };
> + u64 full;
> +};
> +
> struct vcpu_tdx {
> struct kvm_vcpu vcpu;
>
> unsigned long tdvpr_pa;
> unsigned long *tdvpx_pa;
>
> + union tdx_exit_reason exit_reason;
> +
> bool initialized;
>
> /*
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index eba10dabc45f..c939a9d4d927 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -155,6 +155,7 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> int tdx_vcpu_create(struct kvm_vcpu *vcpu);
> void tdx_vcpu_free(struct kvm_vcpu *vcpu);
> void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
> +fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu);
> u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
>
> int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
> @@ -181,6 +182,7 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP
> static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
> static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
> static inline void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) {}
> +static inline fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu) { return EXIT_FASTPATH_NONE; }
> static inline u8 tdx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; }
>
> static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 6d7ca694e1c9..41af9a943d49 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -309,6 +309,7 @@ const struct kvm_stats_header kvm_vcpu_stats_header = {
> };
>
> u64 __read_mostly host_xcr0;
> +EXPORT_SYMBOL_GPL(host_xcr0);
>
> static struct kmem_cache *x86_emulator_cache;
>
> +static int tdx_map_gpa(struct kvm_vcpu *vcpu)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + gpa_t gpa = tdvmcall_a0_read(vcpu);
> + gpa_t size = tdvmcall_a1_read(vcpu);
> + gpa_t end = gpa + size;
> +
> + if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
> + end < gpa ||
> + end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
> + kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
> + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
> + return 1;
> + }
> +
> + return tdx_vp_vmcall_to_user(vcpu);
This will result into exits to userspace for MMIO regions as well. Does it make
sense to only exit to userspace for guest physical memory regions backed by
memslots?
> +}
> +
On 2/4/2023 4:50 pm, Zhi Wang wrote:
> Hi Like:
>
> Would you mind to take a look on this patch? It would be nice to have
> a r-b also from you. :)
>
> On Sun, 12 Mar 2023 10:55:45 -0700
> [email protected] wrote:
>
>> From: Isaku Yamahata <[email protected]>
>>
>> Because TDX KVM doesn't support PMU yet (it's future work of TDX KVM
>> support as another patch series) and pmu_intel.c touches vmx specific
It would be nice to have pmu support for tdx-guest from the very beginning.
If you guys are more open on the tdx development model, I'd like to help on
those features.
>> structure in vcpu initialization, as workaround add dummy structure to
>> struct vcpu_tdx and pmu_intel.c can ignore TDX case.
If the target is not to provide a workaround, how about other variants:
- struct lbr_desc lbr_desc;
- pebs ds_buffer;
?
We also need tdx selftest to verify the unavailability of these features.
Also, it would be great to have TDX's "System Profiling Mode" featue back in the
specification.
>>
>> Signed-off-by: Isaku Yamahata <[email protected]>
>> ---
>> arch/x86/kvm/vmx/pmu_intel.c | 46 +++++++++++++++++++++++++++++++++++-
>> arch/x86/kvm/vmx/pmu_intel.h | 28 ++++++++++++++++++++++
>> arch/x86/kvm/vmx/tdx.h | 8 ++++++-
>> arch/x86/kvm/vmx/vmx.c | 2 +-
>> arch/x86/kvm/vmx/vmx.h | 32 +------------------------
>> 5 files changed, 82 insertions(+), 34 deletions(-)
>> create mode 100644 arch/x86/kvm/vmx/pmu_intel.h
>>
>> diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
>> index e8a3be0b9df9..df1f4ddfa72d 100644
>> --- a/arch/x86/kvm/vmx/pmu_intel.c
>> +++ b/arch/x86/kvm/vmx/pmu_intel.c
>> @@ -19,6 +19,7 @@
>> #include "lapic.h"
>> #include "nested.h"
>> #include "pmu.h"
>> +#include "tdx.h"
>>
>> #define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
>>
>> @@ -40,6 +41,26 @@ static struct {
>> /* mapping between fixed pmc index and intel_arch_events array */
>> static int fixed_pmc_events[] = {1, 0, 7};
>>
>> +struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu)
>> +{
>> +#ifdef CONFIG_INTEL_TDX_HOST
>> + if (is_td_vcpu(vcpu))
>> + return &to_tdx(vcpu)->lbr_desc;
>> +#endif
>> +
>> + return &to_vmx(vcpu)->lbr_desc;
>> +}
>> +
>> +struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
>> +{
>> +#ifdef CONFIG_INTEL_TDX_HOST
>> + if (is_td_vcpu(vcpu))
>> + return &to_tdx(vcpu)->lbr_desc.records;
>> +#endif
>> +
>> + return &to_vmx(vcpu)->lbr_desc.records;
>> +}
>> +
>> static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
>> {
>> struct kvm_pmc *pmc;
>> @@ -172,6 +193,23 @@ static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
>> return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
>> }
>>
>> +bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu)
>> +{
>> + if (is_td_vcpu(vcpu))
>> + return false;
>> + return cpuid_model_is_consistent(vcpu);
>> +}
>> +
>> +bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
>> +{
>> + struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
>> +
>> + if (is_td_vcpu(vcpu))
>> + return false;
>> +
>> + return lbr->nr && (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_LBR_FMT);
>> +}
>> +
>> static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index)
>> {
>> struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu);
>> @@ -282,6 +320,9 @@ int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu)
>> PERF_SAMPLE_BRANCH_USER,
>> };
>>
>> + if (WARN_ON_ONCE(is_td_vcpu(vcpu)))
>> + return 0;
>> +
>> if (unlikely(lbr_desc->event)) {
>> __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
>> return 0;
>> @@ -591,7 +632,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
>> INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
>>
>> perf_capabilities = vcpu_get_perf_capabilities(vcpu);
>> - if (cpuid_model_is_consistent(vcpu) &&
>> + if (intel_pmu_lbr_is_compatible(vcpu) &&
>> (perf_capabilities & PMU_CAP_LBR_FMT))
>> x86_perf_get_lbr(&lbr_desc->records);
>> else
>> @@ -647,6 +688,9 @@ static void intel_pmu_reset(struct kvm_vcpu *vcpu)
>> struct kvm_pmc *pmc = NULL;
>> int i;
>>
>> + if (is_td_vcpu(vcpu))
>> + return;
>> +
>> for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) {
>> pmc = &pmu->gp_counters[i];
>>
>> diff --git a/arch/x86/kvm/vmx/pmu_intel.h b/arch/x86/kvm/vmx/pmu_intel.h
>> new file mode 100644
>> index 000000000000..66bba47c1269
>> --- /dev/null
>> +++ b/arch/x86/kvm/vmx/pmu_intel.h
>> @@ -0,0 +1,28 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +#ifndef __KVM_X86_VMX_PMU_INTEL_H
>> +#define __KVM_X86_VMX_PMU_INTEL_H
>> +
>> +struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu);
>> +struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu);
>> +
>> +bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu);
>> +bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu);
>> +int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu);
>> +
>> +struct lbr_desc {
>> + /* Basic info about guest LBR records. */
>> + struct x86_pmu_lbr records;
>> +
>> + /*
>> + * Emulate LBR feature via passthrough LBR registers when the
>> + * per-vcpu guest LBR event is scheduled on the current pcpu.
>> + *
>> + * The records may be inaccurate if the host reclaims the LBR.
>> + */
>> + struct perf_event *event;
>> +
>> + /* True if LBRs are marked as not intercepted in the MSR bitmap */
>> + bool msr_passthrough;
>> +};
>> +
>> +#endif /* __KVM_X86_VMX_PMU_INTEL_H */
>> diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
>> index 1e00e75b1c5e..5728820fed5e 100644
>> --- a/arch/x86/kvm/vmx/tdx.h
>> +++ b/arch/x86/kvm/vmx/tdx.h
>> @@ -4,6 +4,7 @@
>>
>> #ifdef CONFIG_INTEL_TDX_HOST
>>
>> +#include "pmu_intel.h"
>> #include "tdx_ops.h"
>>
>> struct kvm_tdx {
>> @@ -21,7 +22,12 @@ struct kvm_tdx {
>>
>> struct vcpu_tdx {
>> struct kvm_vcpu vcpu;
>> - /* TDX specific members follow. */
>> +
>> + /*
>> + * Dummy to make pmu_intel not corrupt memory.
>> + * TODO: Support PMU for TDX. Future work.
>> + */
>> + struct lbr_desc lbr_desc;
>> };
>>
>> static inline bool is_td(struct kvm *kvm)
>> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
>> index d23830d92f61..f9e9fd7fde2c 100644
>> --- a/arch/x86/kvm/vmx/vmx.c
>> +++ b/arch/x86/kvm/vmx/vmx.c
>> @@ -2432,7 +2432,7 @@ int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
>> if ((data & PMU_CAP_LBR_FMT) !=
>> (kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT))
>> return 1;
>> - if (!cpuid_model_is_consistent(vcpu))
>> + if (!intel_pmu_lbr_is_compatible(vcpu))
>> return 1;
>> }
>> if (data & PERF_CAP_PEBS_FORMAT) {
>> diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
>> index 2acdc54bc34b..1d15c3c2751b 100644
>> --- a/arch/x86/kvm/vmx/vmx.h
>> +++ b/arch/x86/kvm/vmx/vmx.h
>> @@ -11,6 +11,7 @@
>> #include "capabilities.h"
>> #include "../kvm_cache_regs.h"
>> #include "posted_intr.h"
>> +#include "pmu_intel.h"
>> #include "vmcs.h"
>> #include "vmx_ops.h"
>> #include "../cpuid.h"
>> @@ -105,22 +106,6 @@ static inline bool intel_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
>> return pmu->version > 1;
>> }
>>
>> -struct lbr_desc {
>> - /* Basic info about guest LBR records. */
>> - struct x86_pmu_lbr records;
>> -
>> - /*
>> - * Emulate LBR feature via passthrough LBR registers when the
>> - * per-vcpu guest LBR event is scheduled on the current pcpu.
>> - *
>> - * The records may be inaccurate if the host reclaims the LBR.
>> - */
>> - struct perf_event *event;
>> -
>> - /* True if LBRs are marked as not intercepted in the MSR bitmap */
>> - bool msr_passthrough;
>> -};
>> -
>> /*
>> * The nested_vmx structure is part of vcpu_vmx, and holds information we need
>> * for correct emulation of VMX (i.e., nested VMX) on this vcpu.
>> @@ -650,21 +635,6 @@ static __always_inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
>> return container_of(vcpu, struct vcpu_vmx, vcpu);
>> }
>>
>> -static inline struct lbr_desc *vcpu_to_lbr_desc(struct kvm_vcpu *vcpu)
>> -{
>> - return &to_vmx(vcpu)->lbr_desc;
>> -}
>> -
>> -static inline struct x86_pmu_lbr *vcpu_to_lbr_records(struct kvm_vcpu *vcpu)
>> -{
>> - return &vcpu_to_lbr_desc(vcpu)->records;
>> -}
>> -
>> -static inline bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
>> -{
>> - return !!vcpu_to_lbr_records(vcpu)->nr;
>> -}
>> -
>> void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu);
>> int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu);
>> void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu);
>
>
On Tue, 18 Apr 2023 19:09:04 +0000
Vishal Annapurve <[email protected]> wrote:
> > +static int tdx_map_gpa(struct kvm_vcpu *vcpu)
> > +{
> > + struct kvm *kvm = vcpu->kvm;
> > + gpa_t gpa = tdvmcall_a0_read(vcpu);
> > + gpa_t size = tdvmcall_a1_read(vcpu);
> > + gpa_t end = gpa + size;
> > +
> > + if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
> > + end < gpa ||
> > + end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
> > + kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
> > + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
> > + return 1;
> > + }
> > +
> > + return tdx_vp_vmcall_to_user(vcpu);
>
> This will result into exits to userspace for MMIO regions as well. Does it make
> sense to only exit to userspace for guest physical memory regions backed by
> memslots?
>
I think this is necessary as when passing a PCI device to a TD, the guest needs to convert a MMIO region from private to shared, which is not backed by memslots.
> > +}
> > +
On Sun, 12 Mar 2023 10:56:12 -0700
[email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> TDX doesn't support dirty logging. Report dirty logging isn't supported so
> that device model, for example qemu, can properly handle it. Silently
> ignore on dirty logging on private GFNs of TDX.
>
> Signed-off-by: Sean Christopherson <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> arch/x86/kvm/mmu/mmu.c | 3 +++
> arch/x86/kvm/mmu/tdp_mmu.c | 36 +++++++++++++++++++++++++++++++++++-
> arch/x86/kvm/x86.c | 8 ++++++++
> include/linux/kvm_host.h | 1 +
> virt/kvm/kvm_main.c | 10 +++++++++-
> 5 files changed, 56 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 3d68da838f94..1f250fa8ce36 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -6706,6 +6706,9 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
> for_each_rmap_spte(rmap_head, &iter, sptep) {
> sp = sptep_to_sp(sptep);
>
> + /* Private page dirty logging is not supported yet. */
> + KVM_BUG_ON(is_private_sptep(sptep), kvm);
> +
> /*
> * We cannot do huge page mapping for indirect shadow pages,
> * which are found on the last rmap (level = 1) when not using
> diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
> index a3402b33fa5d..58a236a69ec7 100644
> --- a/arch/x86/kvm/mmu/tdp_mmu.c
> +++ b/arch/x86/kvm/mmu/tdp_mmu.c
> @@ -1474,9 +1474,27 @@ static __always_inline bool kvm_tdp_mmu_handle_gfn(struct kvm *kvm,
> * into this helper allow blocking; it'd be dead, wasteful code.
> */
> for_each_tdp_mmu_root(kvm, root, range->slot->as_id) {
> + gfn_t start;
> + gfn_t end;
> +
> + /*
> + * For now, operation on private GPA, e.g. dirty page logging,
> + * isn't supported yet.
> + */
> + if (is_private_sp(root))
> + continue;
> +
> rcu_read_lock();
>
> - tdp_root_for_each_leaf_pte(iter, root, range->start, range->end)
> + /*
> + * For TDX shared mapping, set GFN shared bit to the range,
> + * so the handler() doesn't need to set it, to avoid duplicated
> + * code in multiple handler()s.
> + */
> + start = kvm_gfn_to_shared(kvm, range->start);
> + end = kvm_gfn_to_shared(kvm, range->end);
> +
> + tdp_root_for_each_leaf_pte(iter, root, start, end)
> ret |= handler(kvm, &iter, range);
>
> rcu_read_unlock();
> @@ -1959,6 +1977,13 @@ void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
> struct kvm_mmu_page *root;
>
> lockdep_assert_held_write(&kvm->mmu_lock);
> + /*
> + * First TDX generation doesn't support clearing dirty bit,
> + * since there's no secure EPT API to support it. For now silently
> + * ignore KVM_CLEAR_DIRTY_LOG.
> + */
> + if (!kvm_arch_dirty_log_supported(kvm))
> + return;
> for_each_tdp_mmu_root(kvm, root, slot->as_id)
> clear_dirty_pt_masked(kvm, root, gfn, mask, wrprot);
> }
> @@ -2078,6 +2103,15 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm,
> bool spte_set = false;
>
> lockdep_assert_held_write(&kvm->mmu_lock);
> +
> + /*
> + * First TDX generation doesn't support write protecting private
> + * mappings, silently ignore the request. KVM_GET_DIRTY_LOG etc
> + * can reach here, no warning.
> + */
> + if (!kvm_arch_dirty_log_supported(kvm))
> + return false;
> +
> for_each_tdp_mmu_root(kvm, root, slot->as_id)
> spte_set |= write_protect_gfn(kvm, root, gfn, min_level);
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index a0960b468c74..6d7ca694e1c9 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -12589,6 +12589,9 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
> u32 new_flags = new ? new->flags : 0;
> bool log_dirty_pages = new_flags & KVM_MEM_LOG_DIRTY_PAGES;
>
> + if (!kvm_arch_dirty_log_supported(kvm) && log_dirty_pages)
> + return;
> +
> /*
> * Update CPU dirty logging if dirty logging is being toggled. This
> * applies to all operations.
> @@ -13561,6 +13564,11 @@ int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
> }
> EXPORT_SYMBOL_GPL(kvm_sev_es_string_io);
>
> +bool kvm_arch_dirty_log_supported(struct kvm *kvm)
> +{
> + return kvm->arch.vm_type != KVM_X86_PROTECTED_VM;
> +}
> +
Maybe introduce a new x86 ops for SNP/TDX to check this separately as SNP
might still support it? With the current approach, I think both SNP/TDX
will be affected. So does the later patch about page-tracking.
Michael, can you confirm this?
> EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
> EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
> EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 5a144497c930..3cd537f4b38b 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1495,6 +1495,7 @@ bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu);
> int kvm_arch_post_init_vm(struct kvm *kvm);
> void kvm_arch_pre_destroy_vm(struct kvm *kvm);
> int kvm_arch_create_vm_debugfs(struct kvm *kvm);
> +bool kvm_arch_dirty_log_supported(struct kvm *kvm);
>
> #ifndef __KVM_HAVE_ARCH_VM_ALLOC
> /*
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 42f01d0d6a49..e9f8225f3406 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -1700,10 +1700,18 @@ static void kvm_replace_memslot(struct kvm *kvm,
> }
> }
>
> +bool __weak kvm_arch_dirty_log_supported(struct kvm *kvm)
> +{
> + return true;
> +}
> +
> static int check_memory_region_flags(struct kvm *kvm,
> const struct kvm_userspace_memory_region2 *mem)
> {
> - u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
> + u32 valid_flags = 0;
> +
> + if (kvm_arch_dirty_log_supported(kvm))
> + valid_flags |= KVM_MEM_LOG_DIRTY_PAGES;
>
> if (kvm_arch_has_private_mem(kvm))
> valid_flags |= KVM_MEM_PRIVATE;
On Sat, Apr 22, 2023, Zhi Wang wrote:
> On Sun, 12 Mar 2023 10:56:12 -0700
> [email protected] wrote:
>
> > From: Isaku Yamahata <[email protected]>
> >
> > TDX doesn't support dirty logging. Report dirty logging isn't supported so
> > that device model, for example qemu, can properly handle it. Silently
> > ignore on dirty logging on private GFNs of TDX.
...
> > +bool kvm_arch_dirty_log_supported(struct kvm *kvm)
> > +{
> > + return kvm->arch.vm_type != KVM_X86_PROTECTED_VM;
> > +}
> > +
>
> Maybe introduce a new x86 ops for SNP/TDX to check this separately as SNP
> might still support it? With the current approach, I think both SNP/TDX
> will be affected. So does the later patch about page-tracking.
This patch is unnecessary, the plan is to disallow dirty logging on memslots that
support private mapping, e.g. we'll end up with something like this:
static int check_memory_region_flags(struct kvm *kvm,
const struct kvm_userspace_memory_region2 *mem)
{
u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
if (kvm_arch_has_private_mem(kvm))
valid_flags |= KVM_MEM_PRIVATE;
/* Dirty logging private memory is not currently supported. */
if (mem->flags & KVM_MEM_PRIVATE)
valid_flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
#ifdef __KVM_HAVE_READONLY_MEM
valid_flags |= KVM_MEM_READONLY;
#endif
if (mem->flags & ~valid_flags)
return -EINVAL;
return 0;
}
> Michael, can you confirm this?
No need to confirm (or deny) at this point, enabling dirty logging for private
memory is not something I want to merge in the initial TDX/SNP series, regardless
of whether or not it's supported by "hardware", a.k.a. trusted firmware.
On Wed, Apr 19, 2023 at 3:38 AM Zhi Wang <[email protected]> wrote:
>
> On Tue, 18 Apr 2023 19:09:04 +0000
> Vishal Annapurve <[email protected]> wrote:
>
> > > +static int tdx_map_gpa(struct kvm_vcpu *vcpu)
> > > +{
> > > + struct kvm *kvm = vcpu->kvm;
> > > + gpa_t gpa = tdvmcall_a0_read(vcpu);
> > > + gpa_t size = tdvmcall_a1_read(vcpu);
> > > + gpa_t end = gpa + size;
> > > +
> > > + if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
> > > + end < gpa ||
> > > + end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
> > > + kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
> > > + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
> > > + return 1;
> > > + }
> > > +
> > > + return tdx_vp_vmcall_to_user(vcpu);
> >
> > This will result into exits to userspace for MMIO regions as well. Does it make
> > sense to only exit to userspace for guest physical memory regions backed by
> > memslots?
> >
> I think this is necessary as when passing a PCI device to a TD, the guest needs to convert a MMIO region from private to shared, which is not backed by memslots.
KVM could internally handle conversion of regions not backed by
private memslots instead of exiting to userspace. This could save time
during guest boot process.
What would be the expectations from userspace for handling mapgpa
operations on MMIO regions? Is it to just convert memory attributes?
> > > +}
> > > +
>
On Wed, Apr 26, 2023, Vishal Annapurve wrote:
> On Wed, Apr 19, 2023 at 3:38 AM Zhi Wang <[email protected]> wrote:
> >
> > On Tue, 18 Apr 2023 19:09:04 +0000
> > Vishal Annapurve <[email protected]> wrote:
> >
> > > > +static int tdx_map_gpa(struct kvm_vcpu *vcpu)
> > > > +{
> > > > + struct kvm *kvm = vcpu->kvm;
> > > > + gpa_t gpa = tdvmcall_a0_read(vcpu);
> > > > + gpa_t size = tdvmcall_a1_read(vcpu);
> > > > + gpa_t end = gpa + size;
> > > > +
> > > > + if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
> > > > + end < gpa ||
> > > > + end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
> > > > + kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
> > > > + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
> > > > + return 1;
> > > > + }
> > > > +
> > > > + return tdx_vp_vmcall_to_user(vcpu);
> > >
> > > This will result into exits to userspace for MMIO regions as well. Does it make
> > > sense to only exit to userspace for guest physical memory regions backed by
> > > memslots?
No, KVM should exit always, e.g. userspace _could_ choose to create a private
memslot in response to the guest's request.
> > I think this is necessary as when passing a PCI device to a TD, the guest
> > needs to convert a MMIO region from private to shared, which is not backed
> > by memslots.
This isn't entirely accurate. If you're talking about emulated MMIO, then there
is no memslot. But the "passing a PCI device" makes it sound like you're talking
about device passthrough, in which case there is a memslot that points at an actual
MMIO region in the host platform.
In either case, conversions should be unnecessary as MMIO regions should not be
enumerated to the guest as supporting encryption, i.e. the guest should know from
time zero that those regions are shared. If we end up with something like Hyper-V's
SVSM-based paravisor, then there might be private emulated MMIO, but such a setup
would also come with its own brand of enlightment in the guest.
> KVM could internally handle conversion of regions not backed by
No, KVM should never internally handle conversions, at least not in the initial
implementation. And if KVM ever does go down this route, it needs dedicated
support in KVM's uAPI since userspace needs to be kept in the loop, i.e. needs
to opt-in and be notified of any conversions.
+static int tdx_map_gpa(struct kvm_vcpu *vcpu)
+{
+ struct kvm *kvm = vcpu->kvm;
+ gpa_t gpa = tdvmcall_a0_read(vcpu);
+ gpa_t size = tdvmcall_a1_read(vcpu);
+ gpa_t end = gpa + size;
+
+ if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
+ end < gpa ||
+ end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
+ kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
According to table 3-6 of the GHCI spec, TDG.VP.VMCALL_ALIGN_ERROR should be
returned if there is an alignment error for the size or start GPA. Right now,
TDG_VP_VMCALL_INVALID_OPERAND is being returned instead. Can this be updated?
+ return 1;
+ }
+
+ return tdx_vp_vmcall_to_user(vcpu);
+}
+
On 3/13/2023 1:55 AM, [email protected] wrote:
> From: Isaku Yamahata <[email protected]>
>
> As the first step to create TDX guest, create/destroy VM struct. Assign
> TDX private Host Key ID (HKID) to the TDX guest for memory encryption and
> allocate extra pages for the TDX guest. On destruction, free allocated
> pages, and HKID.
>
> Before tearing down private page tables, TDX requires some resources of the
> guest TD to be destroyed (i.e. HKID must have been reclaimed, etc). Add
> flush_shadow_all_private callback before tearing down private page tables
> for it.
>
> Add vm_free() of kvm_x86_ops hook at the end of kvm_arch_destroy_vm()
> because some per-VM TDX resources, e.g. TDR, need to be freed after other
> TDX resources, e.g. HKID, were freed.
>
> Co-developed-by: Kai Huang <[email protected]>
> Signed-off-by: Kai Huang <[email protected]>
> Signed-off-by: Sean Christopherson <[email protected]>
> Signed-off-by: Isaku Yamahata <[email protected]>
>
> ---
> Changes v11 -> v12:
> - use cpu_feature_enabled().
>
> Changes v10 -> v11:
> - Fix doule free in tdx_vm_free() by setting NULL.
> - replace struct tdx_td_page tdr and tdcs from struct kvm_tdx with
> unsigned long
> ---
> arch/x86/include/asm/kvm-x86-ops.h | 2 +
> arch/x86/include/asm/kvm_host.h | 2 +
> arch/x86/kvm/vmx/main.c | 35 ++-
> arch/x86/kvm/vmx/tdx.c | 442 ++++++++++++++++++++++++++++-
> arch/x86/kvm/vmx/tdx.h | 6 +-
> arch/x86/kvm/vmx/x86_ops.h | 9 +
> arch/x86/kvm/x86.c | 8 +
> 7 files changed, 498 insertions(+), 6 deletions(-)
...
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 8118647aa8ca..8f87eeeab97c 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -139,19 +139,28 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
>
> #ifdef CONFIG_INTEL_TDX_HOST
> int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> +void tdx_hardware_unsetup(void);
> int tdx_hardware_enable(void);
> bool tdx_is_vm_type_supported(unsigned long type);
> int tdx_dev_ioctl(void __user *argp);
>
> int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
> +int tdx_vm_init(struct kvm *kvm);
> +void tdx_mmu_release_hkid(struct kvm *kvm);
> +void tdx_vm_free(struct kvm *kvm);
> int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> #else
> static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> +static inline void tdx_hardware_unsetup(void) {}
> static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
>
> static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
> +static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
> +static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
> +static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
typo? This function tdx_flush_shadow_all_private is not used anywhere.
> +static inline void tdx_vm_free(struct kvm *kvm) {}
> static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
> #endif
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 7b02dd40ef21..89fd8074c20c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -12398,6 +12398,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
> kvm_page_track_cleanup(kvm);
> kvm_xen_destroy_vm(kvm);
> kvm_hv_destroy_vm(kvm);
> + static_call_cond(kvm_x86_vm_free)(kvm);
> }
>
> static void memslot_rmap_free(struct kvm_memory_slot *slot)
> @@ -12710,6 +12711,13 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
>
> void kvm_arch_flush_shadow_all(struct kvm *kvm)
> {
> + /*
> + * kvm_mmu_zap_all() zaps both private and shared page tables. Before
> + * tearing down private page tables, TDX requires some TD resources to
> + * be destroyed (i.e. keyID must have been reclaimed, etc). Invoke
> + * kvm_x86_flush_shadow_all_private() for this.
> + */
> + static_call_cond(kvm_x86_flush_shadow_all_private)(kvm);
> kvm_mmu_zap_all(kvm);
> }
>
On Wed, Apr 19, 2023 at 04:21:21PM +0800,
Like Xu <[email protected]> wrote:
> On 2/4/2023 4:50 pm, Zhi Wang wrote:
> > Hi Like:
> >
> > Would you mind to take a look on this patch? It would be nice to have
> > a r-b also from you. :)
> >
> > On Sun, 12 Mar 2023 10:55:45 -0700
> > [email protected] wrote:
> >
> > > From: Isaku Yamahata <[email protected]>
> > >
> > > Because TDX KVM doesn't support PMU yet (it's future work of TDX KVM
> > > support as another patch series) and pmu_intel.c touches vmx specific
>
> It would be nice to have pmu support for tdx-guest from the very beginning.
It's supported in the public github repo.
https://github.com/intel/tdx/tree/kvm-upstream-workaround
As this patch series has 100+ patches, I don't want to bloat this patch more.
> If you guys are more open on the tdx development model, I'd like to help on
> those features.
This mainling list is the place.
> > > structure in vcpu initialization, as workaround add dummy structure to
> > > struct vcpu_tdx and pmu_intel.c can ignore TDX case.
>
> If the target is not to provide a workaround, how about other variants:
> - struct lbr_desc lbr_desc;
> - pebs ds_buffer;
> ?
>
> We also need tdx selftest to verify the unavailability of these features.
> Also, it would be great to have TDX's "System Profiling Mode" featue back in
> the specification.
I don't think it's productive. Once merging this patch series, we can move on
to TDX PMU support (or whatever still missing feature) as second (or later)
step.
--
Isaku Yamahata <[email protected]>
On Tue, May 23, 2023 at 04:17:07PM +0800,
"Wen, Qian" <[email protected]> wrote:
> > diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> > index 8118647aa8ca..8f87eeeab97c 100644
> > --- a/arch/x86/kvm/vmx/x86_ops.h
> > +++ b/arch/x86/kvm/vmx/x86_ops.h
> > @@ -139,19 +139,28 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
> >
> > #ifdef CONFIG_INTEL_TDX_HOST
> > int __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
> > +void tdx_hardware_unsetup(void);
> > int tdx_hardware_enable(void);
> > bool tdx_is_vm_type_supported(unsigned long type);
> > int tdx_dev_ioctl(void __user *argp);
> >
> > int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap);
> > +int tdx_vm_init(struct kvm *kvm);
> > +void tdx_mmu_release_hkid(struct kvm *kvm);
> > +void tdx_vm_free(struct kvm *kvm);
> > int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
> > #else
> > static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; }
> > +static inline void tdx_hardware_unsetup(void) {}
> > static inline int tdx_hardware_enable(void) { return -EOPNOTSUPP; }
> > static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> > static inline int tdx_dev_ioctl(void __user *argp) { return -EOPNOTSUPP; };
> >
> > static inline int tdx_vm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { return -EINVAL; };
> > +static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
> > +static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
> > +static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
>
> typo? This function tdx_flush_shadow_all_private is not used anywhere.
Right. It was carry over from the old versions. Will remove the line.
Thanks,
--
Isaku Yamahata <[email protected]>
On Tue, Apr 11, 2023 at 03:49:38PM +0300,
Zhi Wang <[email protected]> wrote:
> On Sun, 12 Mar 2023 10:56:28 -0700
> [email protected] wrote:
>
> > From: Isaku Yamahata <[email protected]>
> >
> > This patch implements running TDX vcpu. Once vcpu runs on the logical
> > processor (LP), the TDX vcpu is associated with it. When the TDX vcpu
> > moves to another LP, the TDX vcpu needs to flush its status on the LP.
> > When destroying TDX vcpu, it needs to complete flush and flush cpu memory
> > cache. Track which LP the TDX vcpu run and flush it as necessary.
> >
> > Do nothing on sched_in event as TDX doesn't support pause loop.
> >
> > TDX vcpu execution requires restoring PMU debug store after returning back
> > to KVM because the TDX module unconditionally resets the value. To reuse
> > the existing code, export perf_restore_debug_store.
> >
> > Signed-off-by: Isaku Yamahata <[email protected]>
> > ---
> > arch/x86/kvm/vmx/main.c | 21 +++++++++++++++++++--
> > arch/x86/kvm/vmx/tdx.c | 32 ++++++++++++++++++++++++++++++++
> > arch/x86/kvm/vmx/tdx.h | 33 +++++++++++++++++++++++++++++++++
> > arch/x86/kvm/vmx/x86_ops.h | 2 ++
> > arch/x86/kvm/x86.c | 1 +
> > 5 files changed, 87 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> > index 55001b34e1f0..2fd6c954590d 100644
> > --- a/arch/x86/kvm/vmx/main.c
> > +++ b/arch/x86/kvm/vmx/main.c
> > @@ -170,6 +170,23 @@ static void vt_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> > vmx_vcpu_reset(vcpu, init_event);
> > }
> >
> > +static int vt_vcpu_pre_run(struct kvm_vcpu *vcpu)
> > +{
> > + if (is_td_vcpu(vcpu))
> > + /* Unconditionally continue to vcpu_run(). */
> > + return 1;
> > +
> > + return vmx_vcpu_pre_run(vcpu);
> > +}
> > +
> > +static fastpath_t vt_vcpu_run(struct kvm_vcpu *vcpu)
> > +{
> > + if (is_td_vcpu(vcpu))
> > + return tdx_vcpu_run(vcpu);
> > +
> > + return vmx_vcpu_run(vcpu);
> > +}
> > +
> > static void vt_flush_tlb_all(struct kvm_vcpu *vcpu)
> > {
> > if (is_td_vcpu(vcpu)) {
> > @@ -323,8 +340,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> > .flush_tlb_gva = vt_flush_tlb_gva,
> > .flush_tlb_guest = vt_flush_tlb_guest,
> >
> > - .vcpu_pre_run = vmx_vcpu_pre_run,
> > - .vcpu_run = vmx_vcpu_run,
> > + .vcpu_pre_run = vt_vcpu_pre_run,
> > + .vcpu_run = vt_vcpu_run,
> > .handle_exit = vmx_handle_exit,
> > .skip_emulated_instruction = vmx_skip_emulated_instruction,
> > .update_emulated_instruction = vmx_update_emulated_instruction,
> > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > index d5a2f769a58d..28a19b14cbbc 100644
> > --- a/arch/x86/kvm/vmx/tdx.c
> > +++ b/arch/x86/kvm/vmx/tdx.c
> > @@ -11,6 +11,9 @@
> > #include "x86.h"
> > #include "mmu.h"
> >
> > +#include <trace/events/kvm.h>
> > +#include "trace.h"
> > +
> > #undef pr_fmt
> > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> >
> > @@ -439,6 +442,35 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> > */
> > }
> >
> > +u64 __tdx_vcpu_run(hpa_t tdvpr, void *regs, u32 regs_mask);
> > +
> > +static noinstr void tdx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
> > + struct vcpu_tdx *tdx)
> > +{
> > + guest_enter_irqoff();
> > + tdx->exit_reason.full = __tdx_vcpu_run(tdx->tdvpr_pa, vcpu->arch.regs, 0);
> > + guest_exit_irqoff();
> > +}
> > +
> > +fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
> > +{
> > + struct vcpu_tdx *tdx = to_tdx(vcpu);
> > +
> > + if (unlikely(vcpu->kvm->vm_bugged)) {
> > + tdx->exit_reason.full = TDX_NON_RECOVERABLE_VCPU;
> > + return EXIT_FASTPATH_NONE;
> > + }
> > +
>
> Maybe check if a TD vCPU is initialized here or in the vcpu_pre_run?
I don't see any point to add tdx_pre_run() and to move the check there.
> Bascially
> I am thinking what if a TD vCPU is not initialized by KVM_TDX_INIT_VCPU (TDVPR
> does not even exist) and now userspace wants to run it. What would be the
> consequence?
TDENTER will fail with error code. Let's add explicit check here for safetly.
if (unlikly(!tdx->initialized))
return -EINVAL;
--
Isaku Yamahata <[email protected]>
On 28/5/2023 4:26 pm, Isaku Yamahata wrote:
> On Wed, Apr 19, 2023 at 04:21:21PM +0800,
> Like Xu <[email protected]> wrote:
>
>> On 2/4/2023 4:50 pm, Zhi Wang wrote:
>>> Hi Like:
>>>
>>> Would you mind to take a look on this patch? It would be nice to have
>>> a r-b also from you. :)
>>>
>>> On Sun, 12 Mar 2023 10:55:45 -0700
>>> [email protected] wrote:
>>>
>>>> From: Isaku Yamahata <[email protected]>
>>>>
>>>> Because TDX KVM doesn't support PMU yet (it's future work of TDX KVM
>>>> support as another patch series) and pmu_intel.c touches vmx specific
>>
>> It would be nice to have pmu support for tdx-guest from the very beginning.
>
> It's supported in the public github repo.
> https://github.com/intel/tdx/tree/kvm-upstream-workaround
> As this patch series has 100+ patches, I don't want to bloat this patch more.
I presume we are talking about 873e2391e729...63761adbf5aa for TD pmu:
A quick glance brought me at least these comments:
(1) how does intel_pmu_save/restore() handle the enabled host LBR/PEBS ?
(2) guest PMI injection may be malicious and could the current guest pmu driver
handle it ?
(3) how do we handle the case when host counters can be enabled before TDENTER
for debuggable TD and support the case like "perf-kvm for both guest and host" ?
My point is actually, changes to perf/core should be CC to the perf reviewers
as early as possible to prevent key player from killing the direction.
>
>
>> If you guys are more open on the tdx development model, I'd like to help on
>> those features.
>
> This mainling list is the place.
Yeah, plus the PUCK and LPC KVM micro-conference.
>
>
>>>> structure in vcpu initialization, as workaround add dummy structure to
>>>> struct vcpu_tdx and pmu_intel.c can ignore TDX case.
>>
>> If the target is not to provide a workaround, how about other variants:
>> - struct lbr_desc lbr_desc;
>> - pebs ds_buffer;
>> ?
>>
>> We also need tdx selftest to verify the unavailability of these features.
>> Also, it would be great to have TDX's "System Profiling Mode" featue back in
>> the specification.
Detailed TD (plus debuggable) PMU selftest would clearly speed up the review
process.
>
> I don't think it's productive. Once merging this patch series, we can move on
> to TDX PMU support (or whatever still missing feature) as second (or later)
> step.
I totally agree that TD PMU (plus debuggable) support should not be the first
part of the
code to be merged in, but the related discussion should be kicked off on day 0.
As a scenario for users using Intel TDX, it's expected to support "System
Profiling Mode",
which was first introduced in 344425-001US but disappeared since version 003.
On Mon, May 29, 2023 at 10:19:16PM +0800,
Like Xu <[email protected]> wrote:
> On 28/5/2023 4:26 pm, Isaku Yamahata wrote:
> > On Wed, Apr 19, 2023 at 04:21:21PM +0800,
> > Like Xu <[email protected]> wrote:
> >
> > > On 2/4/2023 4:50 pm, Zhi Wang wrote:
> > > > Hi Like:
> > > >
> > > > Would you mind to take a look on this patch? It would be nice to have
> > > > a r-b also from you. :)
> > > >
> > > > On Sun, 12 Mar 2023 10:55:45 -0700
> > > > [email protected] wrote:
> > > >
> > > > > From: Isaku Yamahata <[email protected]>
> > > > >
> > > > > Because TDX KVM doesn't support PMU yet (it's future work of TDX KVM
> > > > > support as another patch series) and pmu_intel.c touches vmx specific
> > >
> > > It would be nice to have pmu support for tdx-guest from the very beginning.
> >
> > It's supported in the public github repo.
> > https://github.com/intel/tdx/tree/kvm-upstream-workaround
> > As this patch series has 100+ patches, I don't want to bloat this patch more.
>
> I presume we are talking about 873e2391e729...63761adbf5aa for TD pmu:
>
> A quick glance brought me at least these comments:
>
> (1) how does intel_pmu_save/restore() handle the enabled host LBR/PEBS ?
It's not handled yet. We need to save/restore those MSRs.
> (2) guest PMI injection may be malicious and could the current guest pmu
> driver handle it ?
This isn't specific to PMI. Malicious VMM can inject any interrupt to the
guest at any time. Guest should be prepared for it.
> (3) how do we handle the case when host counters can be enabled before TDENTER
> for debuggable TD and support the case like "perf-kvm for both guest and host" ?
On TDEXIT, those are disabled. VMM has to restore MSRs and enable it again.
There is a window where events can be missed.
> My point is actually, changes to perf/core should be CC to the perf reviewers
> as early as possible to prevent key player from killing the direction.
Sure, agreed.
> > > > > structure in vcpu initialization, as workaround add dummy structure to
> > > > > struct vcpu_tdx and pmu_intel.c can ignore TDX case.
> > >
> > > If the target is not to provide a workaround, how about other variants:
> > > - struct lbr_desc lbr_desc;
> > > - pebs ds_buffer;
> > > ?
> > >
> > > We also need tdx selftest to verify the unavailability of these features.
> > > Also, it would be great to have TDX's "System Profiling Mode" featue back in
> > > the specification.
>
> Detailed TD (plus debuggable) PMU selftest would clearly speed up the review
> process.
The existing KVM PMU selftest can be utilized. Or do you have something else in
mind?
--
Isaku Yamahata <[email protected]>
Isaku Yamahata wrote:
> On Wed, Mar 29, 2023 at 04:17:22PM -0700,
> Isaku Yamahata <[email protected]> wrote:
>
> > On Sat, Mar 25, 2023 at 10:43:06AM +0200,
> > Zhi Wang <[email protected]> wrote:
> >
> > > On Sun, 12 Mar 2023 10:55:40 -0700
> > > [email protected] wrote:
> > >
> > > Does this have to be a new generic ioctl with a dedicated new x86_ops? SNP
> > > does not use it at all and all the system-scoped ioctl of SNP going through
> > > the CCP driver. So getting system-scope information of TDX/SNP will end up
> > > differently.
> > >
> > > Any thought, Sean? Moving getting SNP system-wide information to
> > > KVM dev ioctl seems not ideal and TDX does not have a dedicated driver like
> > > CCP. Maybe make this ioctl TDX-specific? KVM_TDX_DEV_OP?
> >
> > We only need global parameters of the TDX module, and we don't interact with TDX
> > module at this point. One alternative is to export those parameters via sysfs.
> > Also the existence of the sysfs node indicates that the TDX module is
> > loaded(initialized?) or not in addition to boot log. Thus we can drop system
> > scope one.
> > What do you think?
> >
> > Regarding to other TDX KVM specific ioctls (KVM_TDX_INIT_VM, KVM_TDX_INIT_VCPU,
> > KVM_TDX_INIT_MEM_REGION, and KVM_TDX_FINALIZE_VM), they are specific to KVM. So
> > I don't think it can be split out to independent driver.
>
> Here is the patch to export those info via sysfs.
>
> From e0744e506eb92e47d8317e489945a3ba804edfa7 Mon Sep 17 00:00:00 2001
> Message-Id: <e0744e506eb92e47d8317e489945a3ba804edfa7.1680221730.git.isaku.yamahata@intel.com>
> In-Reply-To: <8e0bc0e8e5d435f54f10c7642a862629ef2acb89.1680221729.git.isaku.yamahata@intel.com>
> References: <8e0bc0e8e5d435f54f10c7642a862629ef2acb89.1680221729.git.isaku.yamahata@intel.com>
> From: Isaku Yamahata <[email protected]>
> Date: Thu, 30 Mar 2023 00:05:03 -0700
> Subject: [PATCH] x86/virt/tdx: Export TD config params of TDX module via sysfs
>
> TDX module has parameters for VMM to configure TD. User space VMM, e.g.
> qemu, needs to know it. Export them to user space via sysfs.
>
> TDX 1.0 provides TDH.SYS.INFO to provide system information in
> TDSYSINFO_STRUCT. Its future extensibility is limited because of its
> struct. From TDX 1.5, TDH.SYS.RD(metadata field_id) to read the info
> specified by field id. So instead of exporting TDSYSINFO_STRUCT, adapt
> metadata way to export those system information.
Hi, I came across tdx_sysfs_init() recently and had some comments if
this proposal is going to move forward:
>
> Signed-off-by: Isaku Yamahata <[email protected]>
> ---
> Documentation/ABI/testing/sysfs-firmware-tdx | 23 +++
> arch/x86/include/asm/tdx.h | 33 ++++
> arch/x86/virt/vmx/tdx/tdx.c | 164 +++++++++++++++++++
> arch/x86/virt/vmx/tdx/tdx.h | 18 ++
> 4 files changed, 238 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-firmware-tdx
>
> diff --git a/Documentation/ABI/testing/sysfs-firmware-tdx b/Documentation/ABI/testing/sysfs-firmware-tdx
> new file mode 100644
> index 000000000000..1f26fb178144
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-firmware-tdx
> @@ -0,0 +1,23 @@
> +What: /sys/firmware/tdx/tdx_module/metadata
The TDX module is not "platform firmware" in comparison to the other EFI
and ACPI inhabitants in /sys/firmware. It is especially not static
platform firmware given it needs to be dynamically activated via KVM
module initialization.
Instead, sysfs already has a location for pure software construct
objects to host a sysfs ABI and that is /sys/bus/virtual. I propose a
common "TSM" class device here [1] and TDX can simply publish a named
attribute group, "host", to extend that class device with TDX specifics.
For cross-vendor consistency "host" is a symlink to the CCP device on
AMD.
[1]: http://lore.kernel.org/r/170660662589.224441.11503798303914595072.stgit@dwillia2-xfh.jf.intel.com
> +Date: March 2023
> +KernelVersion: 6.3
> +Contact: Isaku Yamahata <[email protected]>, [email protected]
> +Users: qemu, libvirt
> +Description:
> + The TDX feature requires a firmware that is known as the TDX
> + module. The TDX module exposes its metadata in the following
> + read-only files. The information corresponds to the TDX global
> + metadata specified by 64bit field id.
> + string in lower case. The value is binary.
> + User space VMM like qemu needs refer to them to determine what
> + parameters are needed or allowed to configure guest TDs.
> +
> + ================== ============================================
> + 1900000300000000 ATTRIBUTES_FIXED0
> + 1900000300000001 ATTRIBUTES_FIXED1
> + 1900000300000002 XFAM_FIXED0
> + 1900000300000003 XFAM_FIXED1
> + 9900000100000004 NUM_CPUID_CONFIG
> + 9900000300000400 CPUID_LEAVES
> + 9900000300000500 CPUID_VALUES
> + ================== ============================================
This documentation needs to be per file. With an explanation of how each
file is expected to be used. Someone should reasonably be able to read
this documentation and go write a tool, I don't get that from this
documentation.
> \ No newline at end of file
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index 05870e5ed131..c650ac22a916 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -110,6 +110,39 @@ struct tdx_cpuid_config {
> u32 edx;
> } __packed;
>
> +struct tdx_cpuid_config_leaf {
> + u32 leaf;
> + u32 sub_leaf;
> +} __packed;
> +static_assert(offsetof(struct tdx_cpuid_config, leaf) ==
> + offsetof(struct tdx_cpuid_config_leaf, leaf));
> +static_assert(offsetof(struct tdx_cpuid_config, sub_leaf) ==
> + offsetof(struct tdx_cpuid_config_leaf, sub_leaf));
> +static_assert(offsetofend(struct tdx_cpuid_config, sub_leaf) ==
> + sizeof(struct tdx_cpuid_config_leaf));
> +
> +struct tdx_cpuid_config_value {
> + u32 eax;
> + u32 ebx;
> + u32 ecx;
> + u32 edx;
> +} __packed;
> +static_assert(offsetof(struct tdx_cpuid_config, eax) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, eax));
> +static_assert(offsetof(struct tdx_cpuid_config, ebx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, ebx));
> +static_assert(offsetof(struct tdx_cpuid_config, ecx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, ecx));
> +static_assert(offsetof(struct tdx_cpuid_config, edx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + offsetof(struct tdx_cpuid_config_value, edx));
> +static_assert(offsetofend(struct tdx_cpuid_config, edx) -
> + offsetof(struct tdx_cpuid_config, eax) ==
> + sizeof(struct tdx_cpuid_config_value));
> +
> #define TDSYSINFO_STRUCT_SIZE 1024
> #define TDSYSINFO_STRUCT_ALIGNMENT 1024
>
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index f9f9c1b76501..56ca520d67d6 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -33,6 +33,12 @@
> #include <asm/tdx.h>
> #include "tdx.h"
>
> +#ifdef CONFIG_SYSFS
> +static int tdx_sysfs_init(void);
> +#else
> +static inline int tdx_sysfs_init(void) { return 0;}
> +#endif
> +
> u32 tdx_global_keyid __ro_after_init;
> EXPORT_SYMBOL_GPL(tdx_global_keyid);
> static u32 tdx_guest_keyid_start __ro_after_init;
> @@ -399,6 +405,10 @@ static int __tdx_get_sysinfo(struct tdsysinfo_struct *sysinfo,
> if (ret)
> return ret;
>
> + ret = tdx_sysfs_init();
> + if (ret)
> + return ret;
> +
> pr_info("TDX module: atributes 0x%x, vendor_id 0x%x, major_version %u, minor_version %u, build_date %u, build_num %u",
> sysinfo->attributes, sysinfo->vendor_id,
> sysinfo->major_version, sysinfo->minor_version,
> @@ -1367,3 +1377,157 @@ int tdx_enable(void)
> return ret;
> }
> EXPORT_SYMBOL_GPL(tdx_enable);
> +
> +#ifdef CONFIG_SYSFS
> +
> +static struct kobject *tdx_kobj;
> +static struct kobject *tdx_module_kobj;
> +static struct kobject *tdx_metadata_kobj;
> +
> +#define TDX_METADATA_ATTR(_name, field_id_name, _size) \
> +static struct bin_attribute tdx_metadata_ ## _name = { \
> + .attr = { \
> + .name = field_id_name, \
> + .mode = 0444, \
> + }, \
> + .size = _size, \
> + .read = tdx_metadata_ ## _name ## _show, \
> +}
> +
> +#define TDX_METADATA_ATTR_SHOW(_name, field_id_name) \
> +static ssize_t tdx_metadata_ ## _name ## _show(struct file *filp, struct kobject *kobj, \
> + struct bin_attribute *bin_attr, \
> + char *buf, loff_t offset, size_t count) \
> +{ \
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo); \
> + \
> + return memory_read_from_buffer(buf, count, &offset, \
> + &sysinfo->_name, \
> + sizeof(sysinfo->_name)); \
> +} \
> +TDX_METADATA_ATTR(_name, field_id_name, sizeof_field(struct tdsysinfo_struct, _name))
> +
> +TDX_METADATA_ATTR_SHOW(attributes_fixed0, TDX_METADATA_ATTRIBUTES_FIXED0_NAME);
> +TDX_METADATA_ATTR_SHOW(attributes_fixed1, TDX_METADATA_ATTRIBUTES_FIXED1_NAME);
> +TDX_METADATA_ATTR_SHOW(xfam_fixed0, TDX_METADATA_XFAM_FIXED0_NAME);
> +TDX_METADATA_ATTR_SHOW(xfam_fixed1, TDX_METADATA_XFAM_FIXED1_NAME);
> +
> +static ssize_t tdx_metadata_num_cpuid_config_show(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr,
> + char *buf, loff_t offset, size_t count)
> +{
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
> + /*
> + * Although tdsysinfo_struct.num_cpuid_config is defined as u32 for
> + * alignment, TDX 1.5 defines metadata NUM_CONFIG_CPUID as u16.
> + */
> + u16 tmp = (u16)sysinfo->num_cpuid_config;
> +
> + WARN_ON_ONCE(tmp != sysinfo->num_cpuid_config);
Why crash the kernel here?
> + return memory_read_from_buffer(buf, count, &offset, &tmp, sizeof(tmp));
> +}
> +TDX_METADATA_ATTR(num_cpuid_config, TDX_METADATA_NUM_CPUID_CONFIG_NAME, sizeof(u16));
> +
> +static ssize_t tdx_metadata_cpuid_leaves_show(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr, char *buf,
> + loff_t offset, size_t count)
> +{
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
> + ssize_t r;
> + struct tdx_cpuid_config_leaf *tmp;
> + u32 i;
> +
> + tmp = kmalloc(bin_attr->size, GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
Why is this allocating and then blindly copying bin_attr->size into
@buf? It it either knows that @buf is big enough, no need to allocate,
or if it does not know if @buf is big enough then the copy into @tmp
offers no protection.
> +
> + for (i = 0; i < sysinfo->num_cpuid_config; i++) {
> + struct tdx_cpuid_config *c = &sysinfo->cpuid_configs[i];
> + struct tdx_cpuid_config_leaf *leaf = (struct tdx_cpuid_config_leaf *)c;
> +
> + memcpy(tmp + i, leaf, sizeof(*leaf));
> + }
> +
> + r = memory_read_from_buffer(buf, count, &offset, tmp, bin_attr->size);
> + kfree(tmp);
> + return r;
> +}
> +
> +TDX_METADATA_ATTR(cpuid_leaves, TDX_METADATA_CPUID_LEAVES_NAME, 0);
> +
> +static ssize_t tdx_metadata_cpuid_values_show(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr, char *buf,
> + loff_t offset, size_t count)
> +{
> + struct tdsysinfo_struct *sysinfo = &PADDED_STRUCT(tdsysinfo);
> + struct tdx_cpuid_config_value *tmp;
> + ssize_t r;
> + u32 i;
> +
> + tmp = kmalloc(bin_attr->size, GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
> +
> + for (i = 0; i < sysinfo->num_cpuid_config; i++) {
> + struct tdx_cpuid_config *c = &sysinfo->cpuid_configs[i];
> + struct tdx_cpuid_config_value *value = (struct tdx_cpuid_config_value *)&c->eax;
> +
> + memcpy(tmp + i, value, sizeof(*value));
> + }
> +
> + r = memory_read_from_buffer(buf, count, &offset, tmp, bin_attr->size);
> + kfree(tmp);
> + return r;
> +}
> +
> +TDX_METADATA_ATTR(cpuid_values, TDX_METADATA_CPUID_VALUES_NAME, 0);
> +
> +static struct bin_attribute *tdx_metadata_attrs[] = {
> + &tdx_metadata_attributes_fixed0,
> + &tdx_metadata_attributes_fixed1,
> + &tdx_metadata_xfam_fixed0,
> + &tdx_metadata_xfam_fixed1,
> + &tdx_metadata_num_cpuid_config,
> + &tdx_metadata_cpuid_leaves,
> + &tdx_metadata_cpuid_values,
> + NULL,
> +};
> +
> +static const struct attribute_group tdx_metadata_attr_group = {
> + .bin_attrs = tdx_metadata_attrs,
> +};
> +
> +static int tdx_sysfs_init(void)
> +{
> + struct tdsysinfo_struct *sysinfo;
> + int ret;
> +
> + tdx_kobj = kobject_create_and_add("tdx", firmware_kobj);
> + if (!tdx_kobj) {
> + pr_err("kobject_create_and_add tdx failed\n");
> + return -EINVAL;
> + }
Subsystems, PCI for example [2], are slowly unwinding their usage of dynamic
sysfs_create_*() APIs in favor of static attribute groups. Dynamic
kobject_create_*() usage is even more of an anti-pattern for new code.
This goes away with static attribute group registration.
[2]: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/