2022-10-21 15:38:32

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 00/46] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features

Changes since v11:
- Don't export kvm_vcpu_flush_tlb_guest() and don't call it from
kvm_hv_vcpu_flush_tlb(), these are just leftovers from older versions
[Sean]
- Correctly adjust data_offset/consumed_xmm_halves in kvm_hv_flush_tlb()
in 'all_cpus' case. Leave a comment about the fact that it is
(theoretically) possible to meet non-zero 'var_cnt'.
- Don't use ternary operator in kvm_hv_send_ipi() [Sean]
- Don't inject GP in kvm_hv_hypercall_complete() [Sean]
- Fix various asserts in PV IPI/PV TLB flush selftests [Sean]
- Add a check that L2 has exited due to NMI to 'evmcs_test' [Sean]
- Rebase to the latest kvm/queue [e18d6152ff0f]

Original description:

Currently, KVM handles HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} requests
by flushing the whole VPID and this is sub-optimal. This series introduces
the required mechanism to make handling of these requests more
fine-grained by flushing individual GVAs only (when requested). On this
foundation, "Direct Virtual Flush" Hyper-V feature is implemented. The
feature allows L0 to handle Hyper-V TLB flush hypercalls directly at
L0 without the need to reflect the exit to L1. This has at least two
benefits: reflecting vmexit and the consequent vmenter are avoided + L0
has precise information whether the target vCPU is actually running (and
thus requires a kick).

Sean Christopherson (7):
x86/hyperv: Move VMCB enlightenment definitions to hyperv-tlfs.h
KVM: selftests: Move "struct hv_enlightenments" to x86_64/svm.h
KVM: SVM: Add a proper field for Hyper-V VMCB enlightenments
x86/hyperv: KVM: Rename "hv_enlightenments" to
"hv_vmcb_enlightenments"
KVM: x86: Move clearing of TLB_FLUSH_CURRENT to
kvm_vcpu_flush_tlb_all()
KVM: x86: hyper-v: Add helper to read hypercall data for array
KVM: selftests: Drop helpers to read/write page table entries

Vitaly Kuznetsov (39):
KVM: x86: Rename 'enable_direct_tlbflush' to 'enable_l2_tlb_flush'
KVM: VMX: Rename "vmx/evmcs.{ch}" to "vmx/hyperv.{ch}"
KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag
KVM: x86: hyper-v: Introduce TLB flush fifo
KVM: x86: hyper-v: Handle HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls
gently
KVM: x86: hyper-v: Expose support for extended gva ranges for flush
hypercalls
KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs
x86/hyperv: Introduce
HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK constants
KVM: x86: hyper-v: Use
HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK instead of raw
'64'
KVM: x86: hyper-v: Don't use sparse_set_to_vcpu_mask() in
kvm_hv_send_ipi()
KVM: x86: hyper-v: Create a separate fifo for L2 TLB flush
KVM: x86: hyper-v: Use preallocated buffer in 'struct kvm_vcpu_hv'
instead of on-stack 'sparse_banks'
KVM: nVMX: Keep track of hv_vm_id/hv_vp_id when eVMCS is in use
KVM: nSVM: Keep track of Hyper-V hv_vm_id/hv_vp_id
KVM: x86: Introduce .hv_inject_synthetic_vmexit_post_tlb_flush()
nested hook
KVM: x86: hyper-v: Introduce kvm_hv_is_tlb_flush_hcall()
KVM: x86: hyper-v: L2 TLB flush
KVM: x86: hyper-v: Introduce fast guest_hv_cpuid_has_l2_tlb_flush()
check
KVM: nVMX: hyper-v: Cache VP assist page in 'struct kvm_vcpu_hv'
KVM: nVMX: hyper-v: Enable L2 TLB flush
KVM: x86: Make kvm_hv_get_assist_page() return 0/-errno
KVM: nSVM: hyper-v: Enable L2 TLB flush
KVM: x86: Expose Hyper-V L2 TLB flush feature
KVM: selftests: Better XMM read/write helpers
KVM: selftests: Move HYPERV_LINUX_OS_ID definition to a common header
KVM: selftests: Move the function doing Hyper-V hypercall to a common
header
KVM: selftests: Hyper-V PV IPI selftest
KVM: selftests: Fill in vm->vpages_mapped bitmap in virt_map() too
KVM: selftests: Export vm_vaddr_unused_gap() to make it possible to
request unmapped ranges
KVM: selftests: Hyper-V PV TLB flush selftest
KVM: selftests: Sync 'struct hv_enlightened_vmcs' definition with
hyperv-tlfs.h
KVM: selftests: Sync 'struct hv_vp_assist_page' definition with
hyperv-tlfs.h
KVM: selftests: Move Hyper-V VP assist page enablement out of evmcs.h
KVM: selftests: Split off load_evmcs() from load_vmcs()
KVM: selftests: Create a vendor independent helper to allocate Hyper-V
specific test pages
KVM: selftests: Allocate Hyper-V partition assist page
KVM: selftests: evmcs_test: Introduce L2 TLB flush test
KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test
KVM: selftests: Rename 'evmcs_test' to 'hyperv_evmcs'

arch/x86/include/asm/hyperv-tlfs.h | 37 +
arch/x86/include/asm/kvm-x86-ops.h | 2 +-
arch/x86/include/asm/kvm_host.h | 42 +-
arch/x86/include/asm/svm.h | 7 +-
arch/x86/kvm/Makefile | 5 +-
arch/x86/kvm/hyperv.c | 346 +++++++--
arch/x86/kvm/hyperv.h | 64 +-
arch/x86/kvm/svm/hyperv.c | 18 +
arch/x86/kvm/svm/hyperv.h | 50 +-
arch/x86/kvm/svm/nested.c | 49 +-
arch/x86/kvm/svm/svm.c | 7 +
arch/x86/kvm/svm/svm.h | 5 +-
arch/x86/kvm/svm/svm_onhyperv.c | 8 +-
arch/x86/kvm/svm/svm_onhyperv.h | 25 +-
arch/x86/kvm/trace.h | 21 +-
arch/x86/kvm/vmx/{evmcs.c => hyperv.c} | 45 +-
arch/x86/kvm/vmx/{evmcs.h => hyperv.h} | 12 +-
arch/x86/kvm/vmx/nested.c | 43 +-
arch/x86/kvm/vmx/vmx.c | 7 +-
arch/x86/kvm/vmx/vmx_ops.h | 2 +-
arch/x86/kvm/x86.c | 36 +-
include/asm-generic/hyperv-tlfs.h | 5 +
include/asm-generic/mshyperv.h | 11 +-
tools/testing/selftests/kvm/.gitignore | 4 +-
tools/testing/selftests/kvm/Makefile | 5 +-
.../selftests/kvm/include/kvm_util_base.h | 1 +
.../selftests/kvm/include/x86_64/evmcs.h | 48 +-
.../selftests/kvm/include/x86_64/hyperv.h | 102 +++
.../selftests/kvm/include/x86_64/processor.h | 76 +-
.../selftests/kvm/include/x86_64/svm.h | 26 +-
.../selftests/kvm/include/x86_64/vmx.h | 8 -
tools/testing/selftests/kvm/lib/kvm_util.c | 9 +-
.../testing/selftests/kvm/lib/x86_64/hyperv.c | 46 ++
.../selftests/kvm/lib/x86_64/processor.c | 21 +-
tools/testing/selftests/kvm/lib/x86_64/vmx.c | 45 +-
.../kvm/x86_64/emulator_error_test.c | 6 +-
.../x86_64/{evmcs_test.c => hyperv_evmcs.c} | 71 +-
.../selftests/kvm/x86_64/hyperv_features.c | 25 +-
.../testing/selftests/kvm/x86_64/hyperv_ipi.c | 314 ++++++++
.../selftests/kvm/x86_64/hyperv_svm_test.c | 86 ++-
.../selftests/kvm/x86_64/hyperv_tlb_flush.c | 690 ++++++++++++++++++
41 files changed, 2074 insertions(+), 356 deletions(-)
create mode 100644 arch/x86/kvm/svm/hyperv.c
rename arch/x86/kvm/vmx/{evmcs.c => hyperv.c} (95%)
rename arch/x86/kvm/vmx/{evmcs.h => hyperv.h} (95%)
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/hyperv.c
rename tools/testing/selftests/kvm/x86_64/{evmcs_test.c => hyperv_evmcs.c} (72%)
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c

--
2.37.3


2022-10-21 15:38:39

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 03/46] KVM: SVM: Add a proper field for Hyper-V VMCB enlightenments

From: Sean Christopherson <[email protected]>

Add a union to provide hv_enlightenments side-by-side with the sw_reserved
bytes that Hyper-V's enlightenments overlay. Casting sw_reserved
everywhere is messy, confusing, and unnecessarily unsafe.

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/svm.h | 7 ++++++-
arch/x86/kvm/svm/nested.c | 9 ++++-----
arch/x86/kvm/svm/svm.h | 5 ++++-
arch/x86/kvm/svm/svm_onhyperv.c | 2 +-
arch/x86/kvm/svm/svm_onhyperv.h | 15 +++++++--------
tools/testing/selftests/kvm/include/x86_64/svm.h | 5 ++++-
.../selftests/kvm/x86_64/hyperv_svm_test.c | 3 +--
7 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 0361626841bc..6befed2b30a6 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -5,6 +5,8 @@
#include <uapi/asm/svm.h>
#include <uapi/asm/kvm.h>

+#include <asm/hyperv-tlfs.h>
+
/*
* 32-bit intercept words in the VMCB Control Area, starting
* at Byte offset 000h.
@@ -161,7 +163,10 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
* Offset 0x3e0, 32 bytes reserved
* for use by hypervisor/software.
*/
- u8 reserved_sw[32];
+ union {
+ struct hv_enlightenments hv_enlightenments;
+ u8 reserved_sw[32];
+ };
};


diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 3131c4476b7b..c8e967f6cafe 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -179,8 +179,7 @@ void recalc_intercepts(struct vcpu_svm *svm)
*/
static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
{
- struct hv_enlightenments *hve =
- (struct hv_enlightenments *)svm->nested.ctl.reserved_sw;
+ struct hv_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
int i;

/*
@@ -369,8 +368,8 @@ void __nested_copy_vmcb_control_to_cache(struct kvm_vcpu *vcpu,
/* Hyper-V extensions (Enlightened VMCB) */
if (kvm_hv_hypercall_enabled(vcpu)) {
to->clean = from->clean;
- memcpy(to->reserved_sw, from->reserved_sw,
- sizeof(struct hv_enlightenments));
+ memcpy(&to->hv_enlightenments, &from->hv_enlightenments,
+ sizeof(to->hv_enlightenments));
}
}

@@ -1479,7 +1478,7 @@ static void nested_copy_vmcb_cache_to_control(struct vmcb_control_area *dst,
dst->virt_ext = from->virt_ext;
dst->pause_filter_count = from->pause_filter_count;
dst->pause_filter_thresh = from->pause_filter_thresh;
- /* 'clean' and 'reserved_sw' are not changed by KVM */
+ /* 'clean' and 'hv_enlightenments' are not changed by KVM */
}

static int svm_get_nested_state(struct kvm_vcpu *vcpu,
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 6a7686bf6900..9eb2fc76732f 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -151,7 +151,10 @@ struct vmcb_ctrl_area_cached {
u64 nested_cr3;
u64 virt_ext;
u32 clean;
- u8 reserved_sw[32];
+ union {
+ struct hv_enlightenments hv_enlightenments;
+ u8 reserved_sw[32];
+ };
};

struct svm_nested_state {
diff --git a/arch/x86/kvm/svm/svm_onhyperv.c b/arch/x86/kvm/svm/svm_onhyperv.c
index ed5e79392544..422d00fee24a 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.c
+++ b/arch/x86/kvm/svm/svm_onhyperv.c
@@ -26,7 +26,7 @@ int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
if (!*p_hv_pa_pg)
return -ENOMEM;

- hve = (struct hv_enlightenments *)to_svm(vcpu)->vmcb->control.reserved_sw;
+ hve = &to_svm(vcpu)->vmcb->control.hv_enlightenments;

hve->partition_assist_page = __pa(*p_hv_pa_pg);
hve->hv_vm_id = (unsigned long)vcpu->kvm;
diff --git a/arch/x86/kvm/svm/svm_onhyperv.h b/arch/x86/kvm/svm/svm_onhyperv.h
index 66e61a73caeb..5c664dd7bee2 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.h
+++ b/arch/x86/kvm/svm/svm_onhyperv.h
@@ -17,8 +17,10 @@ int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu);

static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
- struct hv_enlightenments *hve =
- (struct hv_enlightenments *)vmcb->control.reserved_sw;
+ struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;
+
+ BUILD_BUG_ON(sizeof(vmcb->control.hv_enlightenments) !=
+ sizeof(vmcb->control.reserved_sw));

if (npt_enabled &&
ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB)
@@ -60,18 +62,15 @@ static inline void svm_hv_vmcb_dirty_nested_enlightenments(
struct kvm_vcpu *vcpu)
{
struct vmcb *vmcb = to_svm(vcpu)->vmcb;
- struct hv_enlightenments *hve =
- (struct hv_enlightenments *)vmcb->control.reserved_sw;
+ struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;

if (hve->hv_enlightenments_control.msr_bitmap)
vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}

-static inline void svm_hv_update_vp_id(struct vmcb *vmcb,
- struct kvm_vcpu *vcpu)
+static inline void svm_hv_update_vp_id(struct vmcb *vmcb, struct kvm_vcpu *vcpu)
{
- struct hv_enlightenments *hve =
- (struct hv_enlightenments *)vmcb->control.reserved_sw;
+ struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;
u32 vp_index = kvm_hv_get_vpindex(vcpu);

if (hve->hv_vp_id != vp_index) {
diff --git a/tools/testing/selftests/kvm/include/x86_64/svm.h b/tools/testing/selftests/kvm/include/x86_64/svm.h
index 89ce2c6b57fe..6e1527aa3419 100644
--- a/tools/testing/selftests/kvm/include/x86_64/svm.h
+++ b/tools/testing/selftests/kvm/include/x86_64/svm.h
@@ -123,7 +123,10 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
* Offset 0x3e0, 32 bytes reserved
* for use by hypervisor/software.
*/
- u8 reserved_sw[32];
+ union {
+ struct hv_enlightenments hv_enlightenments;
+ u8 reserved_sw[32];
+ };
};


diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
index 2fd64b419928..8ef6a4c83cb1 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
@@ -46,8 +46,7 @@ static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)
{
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
struct vmcb *vmcb = svm->vmcb;
- struct hv_enlightenments *hve =
- (struct hv_enlightenments *)vmcb->control.reserved_sw;
+ struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;

GUEST_SYNC(1);

--
2.37.3

2022-10-21 15:38:47

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 04/46] x86/hyperv: KVM: Rename "hv_enlightenments" to "hv_vmcb_enlightenments"

From: Sean Christopherson <[email protected]>

Now that KVM isn't littered with "struct hv_enlightenments" casts, rename
the struct to "hv_vmcb_enlightenments" to highlight the fact that the
struct is specifically for SVM's VMCB.

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
Reviewed-by: Michael Kelley <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/hyperv-tlfs.h | 2 +-
arch/x86/include/asm/svm.h | 2 +-
arch/x86/kvm/svm/nested.c | 2 +-
arch/x86/kvm/svm/svm.h | 2 +-
arch/x86/kvm/svm/svm_onhyperv.c | 2 +-
arch/x86/kvm/svm/svm_onhyperv.h | 6 +++---
tools/testing/selftests/kvm/include/x86_64/svm.h | 4 ++--
tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c | 2 +-
8 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 245a806a9717..c5e0e5a06c0d 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -602,7 +602,7 @@ struct hv_enlightened_vmcs {
* Hyper-V uses the software reserved 32 bytes in VMCB control area to expose
* SVM enlightenments to guests.
*/
-struct hv_enlightenments {
+struct hv_vmcb_enlightenments {
struct __packed hv_enlightenments_control {
u32 nested_flush_hypercall:1;
u32 msr_bitmap:1;
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 6befed2b30a6..621f064bb7cc 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -164,7 +164,7 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
* for use by hypervisor/software.
*/
union {
- struct hv_enlightenments hv_enlightenments;
+ struct hv_vmcb_enlightenments hv_enlightenments;
u8 reserved_sw[32];
};
};
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index c8e967f6cafe..c2a49aa50a58 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -179,7 +179,7 @@ void recalc_intercepts(struct vcpu_svm *svm)
*/
static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
{
- struct hv_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
+ struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
int i;

/*
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 9eb2fc76732f..5e1178bc9a64 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -152,7 +152,7 @@ struct vmcb_ctrl_area_cached {
u64 virt_ext;
u32 clean;
union {
- struct hv_enlightenments hv_enlightenments;
+ struct hv_vmcb_enlightenments hv_enlightenments;
u8 reserved_sw[32];
};
};
diff --git a/arch/x86/kvm/svm/svm_onhyperv.c b/arch/x86/kvm/svm/svm_onhyperv.c
index 422d00fee24a..52c73a8be72b 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.c
+++ b/arch/x86/kvm/svm/svm_onhyperv.c
@@ -16,7 +16,7 @@

int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
{
- struct hv_enlightenments *hve;
+ struct hv_vmcb_enlightenments *hve;
struct hv_partition_assist_pg **p_hv_pa_pg =
&to_kvm_hv(vcpu->kvm)->hv_pa_pg;

diff --git a/arch/x86/kvm/svm/svm_onhyperv.h b/arch/x86/kvm/svm/svm_onhyperv.h
index 5c664dd7bee2..d5cb2c62e355 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.h
+++ b/arch/x86/kvm/svm/svm_onhyperv.h
@@ -17,7 +17,7 @@ int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu);

static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
- struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;
+ struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;

BUILD_BUG_ON(sizeof(vmcb->control.hv_enlightenments) !=
sizeof(vmcb->control.reserved_sw));
@@ -62,7 +62,7 @@ static inline void svm_hv_vmcb_dirty_nested_enlightenments(
struct kvm_vcpu *vcpu)
{
struct vmcb *vmcb = to_svm(vcpu)->vmcb;
- struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;
+ struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;

if (hve->hv_enlightenments_control.msr_bitmap)
vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
@@ -70,7 +70,7 @@ static inline void svm_hv_vmcb_dirty_nested_enlightenments(

static inline void svm_hv_update_vp_id(struct vmcb *vmcb, struct kvm_vcpu *vcpu)
{
- struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;
+ struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;
u32 vp_index = kvm_hv_get_vpindex(vcpu);

if (hve->hv_vp_id != vp_index) {
diff --git a/tools/testing/selftests/kvm/include/x86_64/svm.h b/tools/testing/selftests/kvm/include/x86_64/svm.h
index 6e1527aa3419..483e6ae12f69 100644
--- a/tools/testing/selftests/kvm/include/x86_64/svm.h
+++ b/tools/testing/selftests/kvm/include/x86_64/svm.h
@@ -58,7 +58,7 @@ enum {
INTERCEPT_RDPRU,
};

-struct hv_enlightenments {
+struct hv_vmcb_enlightenments {
struct __packed hv_enlightenments_control {
u32 nested_flush_hypercall:1;
u32 msr_bitmap:1;
@@ -124,7 +124,7 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
* for use by hypervisor/software.
*/
union {
- struct hv_enlightenments hv_enlightenments;
+ struct hv_vmcb_enlightenments hv_enlightenments;
u8 reserved_sw[32];
};
};
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
index 8ef6a4c83cb1..1c3fc38b4f15 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
@@ -46,7 +46,7 @@ static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)
{
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
struct vmcb *vmcb = svm->vmcb;
- struct hv_enlightenments *hve = &vmcb->control.hv_enlightenments;
+ struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;

GUEST_SYNC(1);

--
2.37.3

2022-10-21 15:38:47

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 05/46] KVM: x86: Rename 'enable_direct_tlbflush' to 'enable_l2_tlb_flush'

To make terminology between Hyper-V-on-KVM and KVM-on-Hyper-V consistent,
rename 'enable_direct_tlbflush' to 'enable_l2_tlb_flush'. The change
eliminates the use of confusing 'direct' and adds the missing underscore.

No functional change.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm-x86-ops.h | 2 +-
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/svm/svm_onhyperv.c | 2 +-
arch/x86/kvm/svm/svm_onhyperv.h | 6 +++---
arch/x86/kvm/vmx/vmx.c | 6 +++---
arch/x86/kvm/x86.c | 6 +++---
6 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 82ba4a564e58..6033b54963a4 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -123,7 +123,7 @@ KVM_X86_OP_OPTIONAL(guest_memory_reclaimed)
KVM_X86_OP(get_msr_feature)
KVM_X86_OP(can_emulate_instruction)
KVM_X86_OP(apic_init_signal_blocked)
-KVM_X86_OP_OPTIONAL(enable_direct_tlbflush)
+KVM_X86_OP_OPTIONAL(enable_l2_tlb_flush)
KVM_X86_OP_OPTIONAL(migrate_timers)
KVM_X86_OP(msr_filter_changed)
KVM_X86_OP(complete_emulated_msr)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7551b6f9c31c..50fe0c7a5571 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1625,7 +1625,7 @@ struct kvm_x86_ops {
void *insn, int insn_len);

bool (*apic_init_signal_blocked)(struct kvm_vcpu *vcpu);
- int (*enable_direct_tlbflush)(struct kvm_vcpu *vcpu);
+ int (*enable_l2_tlb_flush)(struct kvm_vcpu *vcpu);

void (*migrate_timers)(struct kvm_vcpu *vcpu);
void (*msr_filter_changed)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/svm/svm_onhyperv.c b/arch/x86/kvm/svm/svm_onhyperv.c
index 52c73a8be72b..26a89d0da93e 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.c
+++ b/arch/x86/kvm/svm/svm_onhyperv.c
@@ -14,7 +14,7 @@
#include "kvm_onhyperv.h"
#include "svm_onhyperv.h"

-int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
+int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)
{
struct hv_vmcb_enlightenments *hve;
struct hv_partition_assist_pg **p_hv_pa_pg =
diff --git a/arch/x86/kvm/svm/svm_onhyperv.h b/arch/x86/kvm/svm/svm_onhyperv.h
index d5cb2c62e355..45faf84476ce 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.h
+++ b/arch/x86/kvm/svm/svm_onhyperv.h
@@ -13,7 +13,7 @@

static struct kvm_x86_ops svm_x86_ops;

-int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu);
+int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu);

static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
@@ -53,8 +53,8 @@ static inline void svm_hv_hardware_setup(void)

vp_ap->nested_control.features.directhypercall = 1;
}
- svm_x86_ops.enable_direct_tlbflush =
- svm_hv_enable_direct_tlbflush;
+ svm_x86_ops.enable_l2_tlb_flush =
+ svm_hv_enable_l2_tlb_flush;
}
}

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 9dba04b6b019..6b258d9cf53c 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -526,7 +526,7 @@ static unsigned long host_idt_base;
static bool __read_mostly enlightened_vmcs = true;
module_param(enlightened_vmcs, bool, 0444);

-static int hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
+static int hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)
{
struct hv_enlightened_vmcs *evmcs;
struct hv_partition_assist_pg **p_hv_pa_pg =
@@ -8481,8 +8481,8 @@ static int __init vmx_init(void)
}

if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
- vmx_x86_ops.enable_direct_tlbflush
- = hv_enable_direct_tlbflush;
+ vmx_x86_ops.enable_l2_tlb_flush
+ = hv_enable_l2_tlb_flush;

} else {
enlightened_vmcs = false;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4bd5f8a751de..f618187585b1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4480,7 +4480,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
kvm_x86_ops.nested_ops->get_state(NULL, NULL, 0) : 0;
break;
case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
- r = kvm_x86_ops.enable_direct_tlbflush != NULL;
+ r = kvm_x86_ops.enable_l2_tlb_flush != NULL;
break;
case KVM_CAP_HYPERV_ENLIGHTENED_VMCS:
r = kvm_x86_ops.nested_ops->enable_evmcs != NULL;
@@ -5496,10 +5496,10 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
}
return r;
case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
- if (!kvm_x86_ops.enable_direct_tlbflush)
+ if (!kvm_x86_ops.enable_l2_tlb_flush)
return -ENOTTY;

- return static_call(kvm_x86_enable_direct_tlbflush)(vcpu);
+ return static_call(kvm_x86_enable_l2_tlb_flush)(vcpu);

case KVM_CAP_HYPERV_ENFORCE_CPUID:
return kvm_hv_set_enforce_cpuid(vcpu, cap->args[0]);
--
2.37.3

2022-10-21 15:38:56

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 07/46] KVM: x86: Move clearing of TLB_FLUSH_CURRENT to kvm_vcpu_flush_tlb_all()

From: Sean Christopherson <[email protected]>

Clear KVM_REQ_TLB_FLUSH_CURRENT in kvm_vcpu_flush_tlb_all() instead of in
its sole caller that processes KVM_REQ_TLB_FLUSH. Regardless of why/when
kvm_vcpu_flush_tlb_all() is called, flushing "all" TLB entries also
flushes "current" TLB entries.

Ideally, there will never be another caller of kvm_vcpu_flush_tlb_all(),
and moving the handling "requires" extra work to document the ordering
requirement, but future Hyper-V paravirt TLB flushing support will add
similar logic for flush "guest" (Hyper-V can flush a subset of "guest"
entries). And in the Hyper-V case, KVM needs to do more than just clear
the request, the queue of GPAs to flush also needs to purged, and doing
all only in the request path is undesirable as kvm_vcpu_flush_tlb_guest()
does have multiple callers (though it's unlikely KVM's paravirt TLB flush
will coincide with Hyper-V's paravirt TLB flush).

Move the logic even though it adds extra "work" so that KVM will be
consistent with how flush requests are processed when the Hyper-V support
lands.

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/x86.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f618187585b1..fdda5f447f87 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3396,6 +3396,9 @@ static void kvm_vcpu_flush_tlb_all(struct kvm_vcpu *vcpu)
{
++vcpu->stat.tlb_flush;
static_call(kvm_x86_flush_tlb_all)(vcpu);
+
+ /* Flushing all ASIDs flushes the current ASID... */
+ kvm_clear_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
}

static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu)
@@ -10477,12 +10480,15 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_mmu_sync_roots(vcpu);
if (kvm_check_request(KVM_REQ_LOAD_MMU_PGD, vcpu))
kvm_mmu_load_pgd(vcpu);
- if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
+
+ /*
+ * Note, the order matters here, as flushing "all" TLB entries
+ * also flushes the "current" TLB entries, i.e. servicing the
+ * flush "all" will clear any request to flush "current".
+ */
+ if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
kvm_vcpu_flush_tlb_all(vcpu);

- /* Flushing all ASIDs flushes the current ASID... */
- kvm_clear_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
- }
kvm_service_local_tlb_flush_requests(vcpu);

if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) {
--
2.37.3

2022-10-21 15:39:00

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 13/46] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

To handle L2 TLB flush requests, KVM needs to translate the specified
L2 GPA to L1 GPA to read hypercall arguments from there.

No functional change as KVM doesn't handle VMCALL/VMMCALL from L2 yet.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index fca9c51891f5..df1efb821eb0 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -23,6 +23,7 @@
#include "ioapic.h"
#include "cpuid.h"
#include "hyperv.h"
+#include "mmu.h"
#include "xen.h"

#include <linux/cpu.h>
@@ -1908,6 +1909,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
*/
BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);

+ if (!hc->fast && is_guest_mode(vcpu)) {
+ hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
+ if (unlikely(hc->ingpa == INVALID_GPA))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ }
+
if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
if (hc->fast) {
--
2.37.3

2022-10-21 15:39:00

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 11/46] KVM: x86: hyper-v: Handle HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls gently

Currently, HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls are handled
the exact same way as HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE{,EX}: by
flushing the whole VPID and this is sub-optimal. Switch to handling
these requests with 'flush_tlb_gva()' hooks instead. Use the newly
introduced TLB flush fifo to queue the requests.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 111 ++++++++++++++++++++++++++++++++++++------
1 file changed, 95 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 3ba7e2d2fbbd..6868c478617c 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1800,7 +1800,14 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
sparse_banks, consumed_xmm_halves, offset);
}

-static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu)
+static int kvm_hv_get_tlb_flush_entries(struct kvm *kvm, struct kvm_hv_hcall *hc, u64 entries[],
+ int consumed_xmm_halves, gpa_t offset)
+{
+ return kvm_hv_get_hc_data(kvm, hc, hc->rep_cnt, hc->rep_cnt,
+ entries, consumed_xmm_halves, offset);
+}
+
+static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu, u64 *entries, int count)
{
struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
@@ -1811,24 +1818,64 @@ static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu)

tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;

- kfifo_in_spinlocked_noirqsave(&tlb_flush_fifo->entries, &flush_all_entry,
- 1, &tlb_flush_fifo->write_lock);
+ spin_lock(&tlb_flush_fifo->write_lock);
+
+ /*
+ * All entries should fit on the fifo leaving one free for 'flush all'
+ * entry in case another request comes in. In case there's not enough
+ * space, just put 'flush all' entry there.
+ */
+ if (count && entries && count < kfifo_avail(&tlb_flush_fifo->entries)) {
+ WARN_ON(kfifo_in(&tlb_flush_fifo->entries, entries, count) != count);
+ goto out_unlock;
+ }
+
+ /*
+ * Note: full fifo always contains 'flush all' entry, no need to check the
+ * return value.
+ */
+ kfifo_in(&tlb_flush_fifo->entries, &flush_all_entry, 1);
+
+out_unlock:
+ spin_unlock(&tlb_flush_fifo->write_lock);
}

int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ u64 entries[KVM_HV_TLB_FLUSH_FIFO_SIZE];
+ int i, j, count;
+ gva_t gva;

- if (!hv_vcpu)
+ if (!tdp_enabled || !hv_vcpu)
return -EINVAL;

tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;

+ count = kfifo_out(&tlb_flush_fifo->entries, entries, KVM_HV_TLB_FLUSH_FIFO_SIZE);
+
+ for (i = 0; i < count; i++) {
+ if (entries[i] == KVM_HV_TLB_FLUSHALL_ENTRY)
+ goto out_flush_all;
+
+ /*
+ * Lower 12 bits of 'address' encode the number of additional
+ * pages to flush.
+ */
+ gva = entries[i] & PAGE_MASK;
+ for (j = 0; j < (entries[i] & ~PAGE_MASK) + 1; j++)
+ static_call(kvm_x86_flush_tlb_gva)(vcpu, gva + j * PAGE_SIZE);
+
+ ++vcpu->stat.tlb_flush;
+ }
+ return 0;
+
+out_flush_all:
kfifo_reset_out(&tlb_flush_fifo->entries);

- /* Precise flushing isn't implemented yet. */
- return -EOPNOTSUPP;
+ /* Fall back to full flush. */
+ return -ENOSPC;
}

static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
@@ -1837,11 +1884,21 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
struct hv_tlb_flush_ex flush_ex;
struct hv_tlb_flush flush;
DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
+ /*
+ * Normally, there can be no more than 'KVM_HV_TLB_FLUSH_FIFO_SIZE'
+ * entries on the TLB flush fifo. The last entry, however, needs to be
+ * always left free for 'flush all' entry which gets placed when
+ * there is not enough space to put all the requested entries.
+ */
+ u64 __tlb_flush_entries[KVM_HV_TLB_FLUSH_FIFO_SIZE - 1];
+ u64 *tlb_flush_entries;
u64 valid_bank_mask;
u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
struct kvm_vcpu *v;
unsigned long i;
bool all_cpus;
+ int consumed_xmm_halves = 0;
+ gpa_t data_offset;

/*
* The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the
@@ -1857,10 +1914,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
flush.address_space = hc->ingpa;
flush.flags = hc->outgpa;
flush.processor_mask = sse128_lo(hc->xmm[0]);
+ consumed_xmm_halves = 1;
} else {
if (unlikely(kvm_read_guest(kvm, hc->ingpa,
&flush, sizeof(flush))))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ data_offset = sizeof(flush);
}

trace_kvm_hv_flush_tlb(flush.processor_mask,
@@ -1884,10 +1943,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
flush_ex.flags = hc->outgpa;
memcpy(&flush_ex.hv_vp_set,
&hc->xmm[0], sizeof(hc->xmm[0]));
+ consumed_xmm_halves = 2;
} else {
if (unlikely(kvm_read_guest(kvm, hc->ingpa, &flush_ex,
sizeof(flush_ex))))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ data_offset = sizeof(flush_ex);
}

trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
@@ -1902,26 +1963,44 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
if (hc->var_cnt != hweight64(valid_bank_mask))
return HV_STATUS_INVALID_HYPERCALL_INPUT;

- if (all_cpus)
- goto do_flush;
+ if (!all_cpus) {
+ if (!hc->var_cnt)
+ goto ret_success;

- if (!hc->var_cnt)
- goto ret_success;
+ if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks,
+ consumed_xmm_halves, data_offset))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ }
+
+ /*
+ * Hyper-V TLFS doesn't explicitly forbid non-empty sparse vCPU
+ * banks (and, thus, non-zero 'var_cnt') for the 'all vCPUs'
+ * case (HV_GENERIC_SET_ALL). Always adjust data_offset and
+ * consumed_xmm_halves to make sure TLB flush entries are read
+ * from the correct offset.
+ */
+ data_offset += hc->var_cnt * sizeof(sparse_banks[0]);
+ consumed_xmm_halves += hc->var_cnt;
+ }

- if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks, 2,
- offsetof(struct hv_tlb_flush_ex,
- hv_vp_set.bank_contents)))
+ if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE ||
+ hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX ||
+ hc->rep_cnt > ARRAY_SIZE(__tlb_flush_entries)) {
+ tlb_flush_entries = NULL;
+ } else {
+ if (kvm_hv_get_tlb_flush_entries(kvm, hc, __tlb_flush_entries,
+ consumed_xmm_halves, data_offset))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ tlb_flush_entries = __tlb_flush_entries;
}

-do_flush:
/*
* vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
* analyze it here, flush TLB regardless of the specified address space.
*/
if (all_cpus) {
kvm_for_each_vcpu(i, v, kvm)
- hv_tlb_flush_enqueue(v);
+ hv_tlb_flush_enqueue(v, tlb_flush_entries, hc->rep_cnt);

kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
} else {
@@ -1931,7 +2010,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
v = kvm_get_vcpu(kvm, i);
if (!v)
continue;
- hv_tlb_flush_enqueue(v);
+ hv_tlb_flush_enqueue(v, tlb_flush_entries, hc->rep_cnt);
}

kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
--
2.37.3

2022-10-21 15:39:23

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 14/46] x86/hyperv: Introduce HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK constants

It may not come clear from where the magical '64' value used in
__cpumask_to_vpset() come from. Moreover, '64' means both the maximum
sparse bank number as well as the number of vCPUs per bank. Add defines
to make things clear. These defines are also going to be used by KVM.

No functional change.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
include/asm-generic/hyperv-tlfs.h | 5 +++++
include/asm-generic/mshyperv.h | 11 ++++++-----
2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
index fdce7a4cfc6f..020ca9bdbb79 100644
--- a/include/asm-generic/hyperv-tlfs.h
+++ b/include/asm-generic/hyperv-tlfs.h
@@ -399,6 +399,11 @@ struct hv_vpset {
u64 bank_contents[];
} __packed;

+/* The maximum number of sparse vCPU banks which can be encoded by 'struct hv_vpset' */
+#define HV_MAX_SPARSE_VCPU_BANKS (64)
+/* The number of vCPUs in one sparse bank */
+#define HV_VCPUS_PER_SPARSE_BANK (64)
+
/* HvCallSendSyntheticClusterIpi hypercall */
struct hv_send_ipi {
u32 vector;
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index c05d2ce9b6cd..89a529093042 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -214,9 +214,10 @@ static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
{
int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
int this_cpu = smp_processor_id();
+ int max_vcpu_bank = hv_max_vp_index / HV_VCPUS_PER_SPARSE_BANK;

- /* valid_bank_mask can represent up to 64 banks */
- if (hv_max_vp_index / 64 >= 64)
+ /* vpset.valid_bank_mask can represent up to HV_MAX_SPARSE_VCPU_BANKS banks */
+ if (max_vcpu_bank >= HV_MAX_SPARSE_VCPU_BANKS)
return 0;

/*
@@ -224,7 +225,7 @@ static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
* structs are not cleared between calls, we risk flushing unneeded
* vCPUs otherwise.
*/
- for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
+ for (vcpu_bank = 0; vcpu_bank <= max_vcpu_bank; vcpu_bank++)
vpset->bank_contents[vcpu_bank] = 0;

/*
@@ -236,8 +237,8 @@ static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
vcpu = hv_cpu_number_to_vp_number(cpu);
if (vcpu == VP_INVAL)
return -1;
- vcpu_bank = vcpu / 64;
- vcpu_offset = vcpu % 64;
+ vcpu_bank = vcpu / HV_VCPUS_PER_SPARSE_BANK;
+ vcpu_offset = vcpu % HV_VCPUS_PER_SPARSE_BANK;
__set_bit(vcpu_offset, (unsigned long *)
&vpset->bank_contents[vcpu_bank]);
if (vcpu_bank >= nr_bank)
--
2.37.3

2022-10-21 15:39:43

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 16/46] KVM: x86: hyper-v: Don't use sparse_set_to_vcpu_mask() in kvm_hv_send_ipi()

Get rid of on-stack allocation of vcpu_mask and optimize kvm_hv_send_ipi()
for a smaller number of vCPUs in the request. When Hyper-V TLB flush
is in use, HvSendSyntheticClusterIpi{,Ex} calls are not commonly used to
send IPIs to a large number of vCPUs (and are rarely used in general).

Introduce hv_is_vp_in_sparse_set() to directly check if the specified
VP_ID is present in sparse vCPU set.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 42 +++++++++++++++++++++++++++++++-----------
1 file changed, 31 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index df9f9aeedc7c..1d1a65903eb5 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1741,6 +1741,28 @@ static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks,
}
}

+static bool hv_is_vp_in_sparse_set(u32 vp_id, u64 valid_bank_mask, u64 sparse_banks[])
+{
+ int valid_bit_nr = vp_id / HV_VCPUS_PER_SPARSE_BANK;
+ unsigned long sbank;
+
+ if (!test_bit(valid_bit_nr, (unsigned long *)&valid_bank_mask))
+ return false;
+
+ /*
+ * The index into the sparse bank is the number of preceding bits in
+ * the valid mask. Optimize for VMs with <64 vCPUs by skipping the
+ * fancy math if there can't possibly be preceding bits.
+ */
+ if (valid_bit_nr)
+ sbank = hweight64(valid_bank_mask & GENMASK_ULL(valid_bit_nr - 1, 0));
+ else
+ sbank = 0;
+
+ return test_bit(vp_id % HV_VCPUS_PER_SPARSE_BANK,
+ (unsigned long *)&sparse_banks[sbank]);
+}
+
struct kvm_hv_hcall {
u64 param;
u64 ingpa;
@@ -2028,8 +2050,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
}

-static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
- unsigned long *vcpu_bitmap)
+static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,
+ u64 *sparse_banks, u64 valid_bank_mask)
{
struct kvm_lapic_irq irq = {
.delivery_mode = APIC_DM_FIXED,
@@ -2039,7 +2061,9 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
unsigned long i;

kvm_for_each_vcpu(i, vcpu, kvm) {
- if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
+ if (sparse_banks &&
+ !hv_is_vp_in_sparse_set(kvm_hv_get_vpindex(vcpu),
+ valid_bank_mask, sparse_banks))
continue;

/* We fail only when APIC is disabled */
@@ -2052,7 +2076,6 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
struct kvm *kvm = vcpu->kvm;
struct hv_send_ipi_ex send_ipi_ex;
struct hv_send_ipi send_ipi;
- DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
u64 valid_bank_mask;
u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
u32 vector;
@@ -2114,13 +2137,10 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
return HV_STATUS_INVALID_HYPERCALL_INPUT;

- if (all_cpus) {
- kvm_send_ipi_to_many(kvm, vector, NULL);
- } else {
- sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);
-
- kvm_send_ipi_to_many(kvm, vector, vcpu_mask);
- }
+ if (all_cpus)
+ kvm_hv_send_ipi_to_many(kvm, vector, NULL, 0);
+ else
+ kvm_hv_send_ipi_to_many(kvm, vector, sparse_banks, valid_bank_mask);

ret_success:
return HV_STATUS_SUCCESS;
--
2.37.3

2022-10-21 15:40:45

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 01/46] x86/hyperv: Move VMCB enlightenment definitions to hyperv-tlfs.h

From: Sean Christopherson <[email protected]>

Move Hyper-V's VMCB enlightenment definitions to the TLFS header; the
definitions come directly from the TLFS[*], not from KVM.

No functional change intended.

[*] https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/datatypes/hv_svm_enlightened_vmcb_fields

Signed-off-by: Sean Christopherson <[email protected]>
[vitaly: rename VMCB_HV_ -> HV_VMCB_ to match the rest of
hyperv-tlfs.h, keep svm/hyperv.h]
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/hyperv-tlfs.h | 22 +++++++++++++++++++
arch/x86/kvm/svm/hyperv.h | 22 -------------------
arch/x86/kvm/svm/nested.c | 2 +-
arch/x86/kvm/svm/svm_onhyperv.c | 2 +-
arch/x86/kvm/svm/svm_onhyperv.h | 4 ++--
.../selftests/kvm/x86_64/hyperv_svm_test.c | 6 ++---
6 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 3089ec352743..245a806a9717 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -598,6 +598,28 @@ struct hv_enlightened_vmcs {

#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL 0xFFFF

+/*
+ * Hyper-V uses the software reserved 32 bytes in VMCB control area to expose
+ * SVM enlightenments to guests.
+ */
+struct hv_enlightenments {
+ struct __packed hv_enlightenments_control {
+ u32 nested_flush_hypercall:1;
+ u32 msr_bitmap:1;
+ u32 enlightened_npt_tlb: 1;
+ u32 reserved:29;
+ } __packed hv_enlightenments_control;
+ u32 hv_vp_id;
+ u64 hv_vm_id;
+ u64 partition_assist_page;
+ u64 reserved;
+} __packed;
+
+/*
+ * Hyper-V uses the software reserved clean bit in VMCB.
+ */
+#define HV_VMCB_NESTED_ENLIGHTENMENTS 31
+
struct hv_partition_assist_pg {
u32 tlb_lock_count;
};
diff --git a/arch/x86/kvm/svm/hyperv.h b/arch/x86/kvm/svm/hyperv.h
index 7d6d97968fb9..c59544cdf03b 100644
--- a/arch/x86/kvm/svm/hyperv.h
+++ b/arch/x86/kvm/svm/hyperv.h
@@ -10,26 +10,4 @@

#include "../hyperv.h"

-/*
- * Hyper-V uses the software reserved 32 bytes in VMCB
- * control area to expose SVM enlightenments to guests.
- */
-struct hv_enlightenments {
- struct __packed hv_enlightenments_control {
- u32 nested_flush_hypercall:1;
- u32 msr_bitmap:1;
- u32 enlightened_npt_tlb: 1;
- u32 reserved:29;
- } __packed hv_enlightenments_control;
- u32 hv_vp_id;
- u64 hv_vm_id;
- u64 partition_assist_page;
- u64 reserved;
-} __packed;
-
-/*
- * Hyper-V uses the software reserved clean bit in VMCB
- */
-#define VMCB_HV_NESTED_ENLIGHTENMENTS VMCB_SW
-
#endif /* __ARCH_X86_KVM_SVM_HYPERV_H__ */
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 4c620999d230..3131c4476b7b 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -194,7 +194,7 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
if (!svm->nested.force_msr_bitmap_recalc &&
kvm_hv_hypercall_enabled(&svm->vcpu) &&
hve->hv_enlightenments_control.msr_bitmap &&
- (svm->nested.ctl.clean & BIT(VMCB_HV_NESTED_ENLIGHTENMENTS)))
+ (svm->nested.ctl.clean & BIT(HV_VMCB_NESTED_ENLIGHTENMENTS)))
goto set_msrpm_base_pa;

if (!(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_MSR_PROT)))
diff --git a/arch/x86/kvm/svm/svm_onhyperv.c b/arch/x86/kvm/svm/svm_onhyperv.c
index 8cdc62c74a96..ed5e79392544 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.c
+++ b/arch/x86/kvm/svm/svm_onhyperv.c
@@ -32,7 +32,7 @@ int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
hve->hv_vm_id = (unsigned long)vcpu->kvm;
if (!hve->hv_enlightenments_control.nested_flush_hypercall) {
hve->hv_enlightenments_control.nested_flush_hypercall = 1;
- vmcb_mark_dirty(to_svm(vcpu)->vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS);
+ vmcb_mark_dirty(to_svm(vcpu)->vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}

return 0;
diff --git a/arch/x86/kvm/svm/svm_onhyperv.h b/arch/x86/kvm/svm/svm_onhyperv.h
index e2fc59380465..66e61a73caeb 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.h
+++ b/arch/x86/kvm/svm/svm_onhyperv.h
@@ -64,7 +64,7 @@ static inline void svm_hv_vmcb_dirty_nested_enlightenments(
(struct hv_enlightenments *)vmcb->control.reserved_sw;

if (hve->hv_enlightenments_control.msr_bitmap)
- vmcb_mark_dirty(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS);
+ vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}

static inline void svm_hv_update_vp_id(struct vmcb *vmcb,
@@ -76,7 +76,7 @@ static inline void svm_hv_update_vp_id(struct vmcb *vmcb,

if (hve->hv_vp_id != vp_index) {
hve->hv_vp_id = vp_index;
- vmcb_mark_dirty(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS);
+ vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}
}
#else
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
index a380ad7bb9b3..5060fcfe1760 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
@@ -39,7 +39,7 @@ struct hv_enlightenments {
/*
* Hyper-V uses the software reserved clean bit in VMCB
*/
-#define VMCB_HV_NESTED_ENLIGHTENMENTS (1U << 31)
+#define HV_VMCB_NESTED_ENLIGHTENMENTS (1U << 31)

void l2_guest_code(void)
{
@@ -98,14 +98,14 @@ static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)
/* Intercept RDMSR 0xc0000101 without telling KVM about it */
set_bit(2 * (MSR_GS_BASE & 0x1fff), svm->msr + 0x800);
/* Make sure HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP is set */
- vmcb->control.clean |= VMCB_HV_NESTED_ENLIGHTENMENTS;
+ vmcb->control.clean |= HV_VMCB_NESTED_ENLIGHTENMENTS;
run_guest(vmcb, svm->vmcb_gpa);
/* Make sure we don't see SVM_EXIT_MSR here so eMSR bitmap works */
GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
vmcb->save.rip += 3; /* vmcall */

/* Now tell KVM we've changed MSR-Bitmap */
- vmcb->control.clean &= ~VMCB_HV_NESTED_ENLIGHTENMENTS;
+ vmcb->control.clean &= ~HV_VMCB_NESTED_ENLIGHTENMENTS;
run_guest(vmcb, svm->vmcb_gpa);
GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_MSR);
vmcb->save.rip += 2; /* rdmsr */
--
2.37.3

2022-10-21 15:40:51

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 12/46] KVM: x86: hyper-v: Expose support for extended gva ranges for flush hypercalls

Extended GVA ranges support bit seems to indicate whether lower 12
bits of GVA can be used to specify up to 4095 additional consequent
GVAs to flush. This is somewhat described in TLFS.

Previously, KVM was handling HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX}
requests by flushing the whole VPID so technically, extended GVA
ranges were already supported. As such requests are handled more
gently now, advertizing support for extended ranges starts making
sense to reduce the size of TLB flush requests.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/hyperv-tlfs.h | 2 ++
arch/x86/kvm/hyperv.c | 1 +
2 files changed, 3 insertions(+)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index c5e0e5a06c0d..6639979302ab 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -61,6 +61,8 @@
#define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE BIT(10)
/* Support for debug MSRs available */
#define HV_FEATURE_DEBUG_MSRS_AVAILABLE BIT(11)
+/* Support for extended gva ranges for flush hypercalls available */
+#define HV_FEATURE_EXT_GVA_RANGES_FLUSH BIT(14)
/*
* Support for returning hypercall output block via XMM
* registers is available
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 6868c478617c..fca9c51891f5 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -2641,6 +2641,7 @@ int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
ent->ebx |= HV_DEBUGGING;
ent->edx |= HV_X64_GUEST_DEBUGGING_AVAILABLE;
ent->edx |= HV_FEATURE_DEBUG_MSRS_AVAILABLE;
+ ent->edx |= HV_FEATURE_EXT_GVA_RANGES_FLUSH;

/*
* Direct Synthetic timers only make sense with in-kernel
--
2.37.3

2022-10-21 15:41:23

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 15/46] KVM: x86: hyper-v: Use HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK instead of raw '64'

It may not be clear from where the '64' limit for the maximum sparse
bank number comes from, use HV_MAX_SPARSE_VCPU_BANKS define instead.
Use HV_VCPUS_PER_SPARSE_BANK in KVM_HV_MAX_SPARSE_VCPU_SET_BITS's
definition. Opportunistically adjust the comment around BUILD_BUG_ON().

No functional change.

Reviewed-by: Maxim Levitsky <[email protected]>
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index df1efb821eb0..df9f9aeedc7c 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -40,7 +40,7 @@
#include "irq.h"
#include "fpu.h"

-#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64)
+#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, HV_VCPUS_PER_SPARSE_BANK)

static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
bool vcpu_kick);
@@ -1793,7 +1793,7 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
u64 *sparse_banks, int consumed_xmm_halves,
gpa_t offset)
{
- if (hc->var_cnt > 64)
+ if (hc->var_cnt > HV_MAX_SPARSE_VCPU_BANKS)
return -EINVAL;

/* Cap var_cnt to ignore banks that cannot contain a legal VP index. */
@@ -1902,12 +1902,11 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
gpa_t data_offset;

/*
- * The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the
- * valid mask is a u64. Fail the build if KVM's max allowed number of
- * vCPUs (>4096) would exceed this limit, KVM will additional changes
- * for Hyper-V support to avoid setting the guest up to fail.
+ * The Hyper-V TLFS doesn't allow more than HV_MAX_SPARSE_VCPU_BANKS
+ * sparse banks. Fail the build if KVM's max allowed number of
+ * vCPUs (>4096) exceeds this limit.
*/
- BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
+ BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > HV_MAX_SPARSE_VCPU_BANKS);

if (!hc->fast && is_guest_mode(vcpu)) {
hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
--
2.37.3

2022-10-21 15:43:46

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 44/46] KVM: selftests: evmcs_test: Introduce L2 TLB flush test

Enable Hyper-V L2 TLB flush and check that Hyper-V TLB flush hypercalls
from L2 don't exit to L1 unless 'TlbLockCount' is set in the
Partition assist page.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/evmcs.h | 2 +
.../testing/selftests/kvm/x86_64/evmcs_test.c | 52 ++++++++++++++++++-
2 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/evmcs.h b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
index 94d6059e9a12..901caf0e0939 100644
--- a/tools/testing/selftests/kvm/include/x86_64/evmcs.h
+++ b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
@@ -237,6 +237,8 @@ struct hv_enlightened_vmcs {
#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_ENLIGHTENMENTSCONTROL BIT(15)
#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL 0xFFFF

+#define HV_VMX_SYNTHETIC_EXIT_REASON_TRAP_AFTER_FLUSH 0x10000031
+
extern struct hv_enlightened_vmcs *current_evmcs;

int vcpu_enable_evmcs(struct kvm_vcpu *vcpu);
diff --git a/tools/testing/selftests/kvm/x86_64/evmcs_test.c b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
index 74f076ba574b..16d98f8fc50c 100644
--- a/tools/testing/selftests/kvm/x86_64/evmcs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
@@ -16,6 +16,7 @@

#include "kvm_util.h"

+#include "hyperv.h"
#include "vmx.h"

static int ud_count;
@@ -48,6 +49,8 @@ static inline void rdmsr_gs_base(void)

void l2_guest_code(void)
{
+ u64 unused;
+
GUEST_SYNC(7);

GUEST_SYNC(8);
@@ -64,15 +67,33 @@ void l2_guest_code(void)
vmcall();
rdmsr_gs_base(); /* intercepted */

+ /* L2 TLB flush tests */
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE | HV_HYPERCALL_FAST_BIT, 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES | HV_FLUSH_ALL_PROCESSORS);
+ rdmsr_fs_base();
+ /*
+ * Note: hypercall status (RAX) is not preserved correctly by L1 after
+ * synthetic vmexit, use unchecked version.
+ */
+ __hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE | HV_HYPERCALL_FAST_BIT, 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES | HV_FLUSH_ALL_PROCESSORS,
+ &unused);
+ /* Make sure we're not issuing Hyper-V TLB flush call again */
+ __asm__ __volatile__ ("mov $0xdeadbeef, %rcx");
+
/* Done, exit to L1 and never come back. */
vmcall();
}

-void guest_code(struct vmx_pages *vmx_pages, struct hyperv_test_pages *hv_pages)
+void guest_code(struct vmx_pages *vmx_pages, struct hyperv_test_pages *hv_pages,
+ vm_vaddr_t hv_hcall_page_gpa)
{
#define L2_GUEST_STACK_SIZE 64
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];

+ wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
+ wrmsr(HV_X64_MSR_HYPERCALL, hv_hcall_page_gpa);
+
x2apic_enable();

GUEST_SYNC(1);
@@ -102,7 +123,17 @@ void guest_code(struct vmx_pages *vmx_pages, struct hyperv_test_pages *hv_pages)
vmwrite(PIN_BASED_VM_EXEC_CONTROL, vmreadz(PIN_BASED_VM_EXEC_CONTROL) |
PIN_BASED_NMI_EXITING);

+ /* L2 TLB flush setup */
+ current_evmcs->partition_assist_page = hv_pages->partition_assist_gpa;
+ current_evmcs->hv_enlightenments_control.nested_flush_hypercall = 1;
+ current_evmcs->hv_vm_id = 1;
+ current_evmcs->hv_vp_id = 1;
+ current_vp_assist->nested_control.features.directhypercall = 1;
+ *(u32 *)(hv_pages->partition_assist) = 0;
+
GUEST_ASSERT(!vmlaunch());
+ GUEST_ASSERT_EQ(vmreadz(VM_EXIT_REASON), EXIT_REASON_EXCEPTION_NMI);
+ GUEST_ASSERT_EQ((vmreadz(VM_EXIT_INTR_INFO) & 0xff), NMI_VECTOR);
GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);

/*
@@ -146,6 +177,18 @@ void guest_code(struct vmx_pages *vmx_pages, struct hyperv_test_pages *hv_pages)
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ);
current_evmcs->guest_rip += 2; /* rdmsr */

+ /*
+ * L2 TLB flush test. First VMCALL should be handled directly by L0,
+ * no VMCALL exit expected.
+ */
+ GUEST_ASSERT(!vmresume());
+ GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ);
+ current_evmcs->guest_rip += 2; /* rdmsr */
+ /* Enable synthetic vmexit */
+ *(u32 *)(hv_pages->partition_assist) = 1;
+ GUEST_ASSERT(!vmresume());
+ GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == HV_VMX_SYNTHETIC_EXIT_REASON_TRAP_AFTER_FLUSH);
+
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
GUEST_SYNC(11);
@@ -199,6 +242,7 @@ static struct kvm_vcpu *save_restore_vm(struct kvm_vm *vm,
int main(int argc, char *argv[])
{
vm_vaddr_t vmx_pages_gva = 0, hv_pages_gva = 0;
+ vm_vaddr_t hcall_page;

struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
@@ -212,12 +256,16 @@ int main(int argc, char *argv[])
TEST_REQUIRE(kvm_has_cap(KVM_CAP_NESTED_STATE));
TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS));

+ hcall_page = vm_vaddr_alloc_pages(vm, 1);
+ memset(addr_gva2hva(vm, hcall_page), 0x0, getpagesize());
+
vcpu_set_hv_cpuid(vcpu);
vcpu_enable_evmcs(vcpu);

vcpu_alloc_vmx(vm, &vmx_pages_gva);
vcpu_alloc_hyperv_test_pages(vm, &hv_pages_gva);
- vcpu_args_set(vcpu, 2, vmx_pages_gva, hv_pages_gva);
+ vcpu_args_set(vcpu, 3, vmx_pages_gva, hv_pages_gva, addr_gva2gpa(vm, hcall_page));
+ vcpu_set_msr(vcpu, HV_X64_MSR_VP_INDEX, vcpu->id);

vm_init_descriptor_tables(vm);
vcpu_init_descriptor_tables(vcpu);
--
2.37.3

2022-10-21 15:44:25

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 41/46] KVM: selftests: Split off load_evmcs() from load_vmcs()

In preparation to putting Hyper-V specific test pages to a dedicated
struct, move eVMCS load logic from load_vmcs(). Tests call load_vmcs()
directly and the only one which needs 'enlightened' version is
evmcs_test so there's not much gain in having this merged.

Temporary pass both GPA and HVA to load_evmcs().

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/evmcs.h | 10 ++++++
tools/testing/selftests/kvm/lib/x86_64/vmx.c | 33 ++++++++-----------
.../testing/selftests/kvm/x86_64/evmcs_test.c | 4 +--
3 files changed, 25 insertions(+), 22 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/evmcs.h b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
index 2530b5aeb4ba..59b60d45b8f6 100644
--- a/tools/testing/selftests/kvm/include/x86_64/evmcs.h
+++ b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
@@ -256,6 +256,16 @@ static inline int evmcs_vmptrld(uint64_t vmcs_pa, void *vmcs)
return 0;
}

+static inline bool load_evmcs(uint64_t enlightened_vmcs_gpa, void *enlightened_vmcs)
+{
+ if (evmcs_vmptrld(enlightened_vmcs_gpa, enlightened_vmcs))
+ return false;
+
+ current_evmcs->revision_id = EVMCS_VERSION;
+
+ return true;
+}
+
static inline int evmcs_vmptrst(uint64_t *value)
{
*value = current_vp_assist->current_nested_vmcs &
diff --git a/tools/testing/selftests/kvm/lib/x86_64/vmx.c b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
index d21049c38fc5..40e4f427a3ec 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/vmx.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
@@ -171,26 +171,19 @@ bool prepare_for_vmx_operation(struct vmx_pages *vmx)

bool load_vmcs(struct vmx_pages *vmx)
{
- if (!enable_evmcs) {
- /* Load a VMCS. */
- *(uint32_t *)(vmx->vmcs) = vmcs_revision();
- if (vmclear(vmx->vmcs_gpa))
- return false;
-
- if (vmptrld(vmx->vmcs_gpa))
- return false;
-
- /* Setup shadow VMCS, do not load it yet. */
- *(uint32_t *)(vmx->shadow_vmcs) =
- vmcs_revision() | 0x80000000ul;
- if (vmclear(vmx->shadow_vmcs_gpa))
- return false;
- } else {
- if (evmcs_vmptrld(vmx->enlightened_vmcs_gpa,
- vmx->enlightened_vmcs))
- return false;
- current_evmcs->revision_id = EVMCS_VERSION;
- }
+ /* Load a VMCS. */
+ *(uint32_t *)(vmx->vmcs) = vmcs_revision();
+ if (vmclear(vmx->vmcs_gpa))
+ return false;
+
+ if (vmptrld(vmx->vmcs_gpa))
+ return false;
+
+ /* Setup shadow VMCS, do not load it yet. */
+ *(uint32_t *)(vmx->shadow_vmcs) =
+ vmcs_revision() | 0x80000000ul;
+ if (vmclear(vmx->shadow_vmcs_gpa))
+ return false;

return true;
}
diff --git a/tools/testing/selftests/kvm/x86_64/evmcs_test.c b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
index 9007fb04343b..5a4c8b1873aa 100644
--- a/tools/testing/selftests/kvm/x86_64/evmcs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
@@ -81,10 +81,10 @@ void guest_code(struct vmx_pages *vmx_pages)
enable_vp_assist(vmx_pages->vp_assist_gpa, vmx_pages->vp_assist);
evmcs_enable();

- GUEST_ASSERT(vmx_pages->vmcs_gpa);
GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
GUEST_SYNC(3);
- GUEST_ASSERT(load_vmcs(vmx_pages));
+ GUEST_ASSERT(load_evmcs(vmx_pages->enlightened_vmcs_gpa,
+ vmx_pages->enlightened_vmcs));
GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa);

GUEST_SYNC(4);
--
2.37.3

2022-10-21 15:51:59

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 24/46] KVM: x86: hyper-v: Introduce fast guest_hv_cpuid_has_l2_tlb_flush() check

Introduce a helper to quickly check if KVM needs to handle VMCALL/VMMCALL
from L2 in L0 to process L2 TLB flush requests.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 7706e203ff43..bd698eb2bda1 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -174,6 +174,14 @@ static inline void kvm_hv_vcpu_purge_flush_tlb(struct kvm_vcpu *vcpu)
kfifo_reset_out(&tlb_flush_fifo->entries);
}

+static inline bool guest_hv_cpuid_has_l2_tlb_flush(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+
+ return hv_vcpu &&
+ (hv_vcpu->cpuid_cache.nested_eax & HV_X64_NESTED_DIRECT_FLUSH);
+}
+
static inline bool kvm_hv_is_tlb_flush_hcall(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
--
2.37.3

2022-10-21 15:52:05

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 40/46] KVM: selftests: Move Hyper-V VP assist page enablement out of evmcs.h

Hyper-V VP assist page is not eVMCS specific, it is also used for
enlightened nSVM. Move the code to vendor neutral place.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/include/x86_64/evmcs.h | 40 +------------------
.../selftests/kvm/include/x86_64/hyperv.h | 31 ++++++++++++++
.../testing/selftests/kvm/lib/x86_64/hyperv.c | 21 ++++++++++
.../testing/selftests/kvm/x86_64/evmcs_test.c | 1 +
5 files changed, 56 insertions(+), 38 deletions(-)
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/hyperv.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index c4342dd427a2..eee6421cf4a8 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -52,6 +52,7 @@ LIBKVM_STRING += lib/string_override.c

LIBKVM_x86_64 += lib/x86_64/apic.c
LIBKVM_x86_64 += lib/x86_64/handlers.S
+LIBKVM_x86_64 += lib/x86_64/hyperv.c
LIBKVM_x86_64 += lib/x86_64/perf_test_util.c
LIBKVM_x86_64 += lib/x86_64/processor.c
LIBKVM_x86_64 += lib/x86_64/svm.c
diff --git a/tools/testing/selftests/kvm/include/x86_64/evmcs.h b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
index efdc62704f27..2530b5aeb4ba 100644
--- a/tools/testing/selftests/kvm/include/x86_64/evmcs.h
+++ b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
@@ -10,6 +10,7 @@
#define SELFTEST_KVM_EVMCS_H

#include <stdint.h>
+#include "hyperv.h"
#include "vmx.h"

#define u16 uint16_t
@@ -20,27 +21,6 @@

extern bool enable_evmcs;

-struct hv_nested_enlightenments_control {
- struct {
- __u32 directhypercall:1;
- __u32 reserved:31;
- } features;
- struct {
- __u32 reserved;
- } hypercallControls;
-} __packed;
-
-/* Define virtual processor assist page structure. */
-struct hv_vp_assist_page {
- __u32 apic_assist;
- __u32 reserved1;
- __u64 vtl_control[3];
- struct hv_nested_enlightenments_control nested_control;
- __u8 enlighten_vmentry;
- __u8 reserved2[7];
- __u64 current_nested_vmcs;
-} __packed;
-
struct hv_enlightened_vmcs {
u32 revision_id;
u32 abort;
@@ -257,29 +237,13 @@ struct hv_enlightened_vmcs {
#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_ENLIGHTENMENTSCONTROL BIT(15)
#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL 0xFFFF

-#define HV_X64_MSR_VP_ASSIST_PAGE 0x40000073
-#define HV_X64_MSR_VP_ASSIST_PAGE_ENABLE 0x00000001
-#define HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT 12
-#define HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_MASK \
- (~((1ull << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) - 1))
-
extern struct hv_enlightened_vmcs *current_evmcs;
-extern struct hv_vp_assist_page *current_vp_assist;

int vcpu_enable_evmcs(struct kvm_vcpu *vcpu);

-static inline int enable_vp_assist(uint64_t vp_assist_pa, void *vp_assist)
+static inline void evmcs_enable(void)
{
- u64 val = (vp_assist_pa & HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_MASK) |
- HV_X64_MSR_VP_ASSIST_PAGE_ENABLE;
-
- wrmsr(HV_X64_MSR_VP_ASSIST_PAGE, val);
-
- current_vp_assist = vp_assist;
-
enable_evmcs = true;
-
- return 0;
}

static inline int evmcs_vmptrld(uint64_t vmcs_pa, void *vmcs)
diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index e2cda9f9f409..3a17431c5771 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -236,4 +236,35 @@ static inline void hyperv_write_xmm_input(void *data, int n_sse_regs)
/* Proper HV_X64_MSR_GUEST_OS_ID value */
#define HYPERV_LINUX_OS_ID ((u64)0x8100 << 48)

+#define HV_X64_MSR_VP_ASSIST_PAGE 0x40000073
+#define HV_X64_MSR_VP_ASSIST_PAGE_ENABLE 0x00000001
+#define HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT 12
+#define HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_MASK \
+ (~((1ull << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) - 1))
+
+struct hv_nested_enlightenments_control {
+ struct {
+ __u32 directhypercall:1;
+ __u32 reserved:31;
+ } features;
+ struct {
+ __u32 reserved;
+ } hypercallControls;
+} __packed;
+
+/* Define virtual processor assist page structure. */
+struct hv_vp_assist_page {
+ __u32 apic_assist;
+ __u32 reserved1;
+ __u64 vtl_control[3];
+ struct hv_nested_enlightenments_control nested_control;
+ __u8 enlighten_vmentry;
+ __u8 reserved2[7];
+ __u64 current_nested_vmcs;
+} __packed;
+
+extern struct hv_vp_assist_page *current_vp_assist;
+
+int enable_vp_assist(uint64_t vp_assist_pa, void *vp_assist);
+
#endif /* !SELFTEST_KVM_HYPERV_H */
diff --git a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
new file mode 100644
index 000000000000..32dc0afd9e5b
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Hyper-V specific functions.
+ *
+ * Copyright (C) 2021, Red Hat Inc.
+ */
+#include <stdint.h>
+#include "processor.h"
+#include "hyperv.h"
+
+int enable_vp_assist(uint64_t vp_assist_pa, void *vp_assist)
+{
+ uint64_t val = (vp_assist_pa & HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_MASK) |
+ HV_X64_MSR_VP_ASSIST_PAGE_ENABLE;
+
+ wrmsr(HV_X64_MSR_VP_ASSIST_PAGE, val);
+
+ current_vp_assist = vp_assist;
+
+ return 0;
+}
diff --git a/tools/testing/selftests/kvm/x86_64/evmcs_test.c b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
index 99bc202243d2..9007fb04343b 100644
--- a/tools/testing/selftests/kvm/x86_64/evmcs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
@@ -79,6 +79,7 @@ void guest_code(struct vmx_pages *vmx_pages)
GUEST_SYNC(2);

enable_vp_assist(vmx_pages->vp_assist_gpa, vmx_pages->vp_assist);
+ evmcs_enable();

GUEST_ASSERT(vmx_pages->vmcs_gpa);
GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
--
2.37.3

2022-10-21 15:52:05

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 10/46] KVM: x86: hyper-v: Add helper to read hypercall data for array

From: Sean Christopherson <[email protected]>

Move the guts of kvm_get_sparse_vp_set() to a helper so that the code for
reading a guest-provided array can be reused in the future, e.g. for
getting a list of virtual addresses whose TLB entries need to be flushed.

Opportunisticaly swap the order of the data and XMM adjustment so that
the XMM/gpa offsets are bundled together.

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 53 +++++++++++++++++++++++++++----------------
1 file changed, 33 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 9d9a5ff2d54b..3ba7e2d2fbbd 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1753,38 +1753,51 @@ struct kvm_hv_hcall {
sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS];
};

-static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
- int consumed_xmm_halves,
- u64 *sparse_banks, gpa_t offset)
-{
- u16 var_cnt;
- int i;

- if (hc->var_cnt > 64)
- return -EINVAL;
-
- /* Ignore banks that cannot possibly contain a legal VP index. */
- var_cnt = min_t(u16, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS);
+static int kvm_hv_get_hc_data(struct kvm *kvm, struct kvm_hv_hcall *hc,
+ u16 orig_cnt, u16 cnt_cap, u64 *data,
+ int consumed_xmm_halves, gpa_t offset)
+{
+ /*
+ * Preserve the original count when ignoring entries via a "cap", KVM
+ * still needs to validate the guest input (though the non-XMM path
+ * punts on the checks).
+ */
+ u16 cnt = min(orig_cnt, cnt_cap);
+ int i, j;

if (hc->fast) {
/*
* Each XMM holds two sparse banks, but do not count halves that
* have already been consumed for hypercall parameters.
*/
- if (hc->var_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - consumed_xmm_halves)
+ if (orig_cnt > 2 * HV_HYPERCALL_MAX_XMM_REGISTERS - consumed_xmm_halves)
return HV_STATUS_INVALID_HYPERCALL_INPUT;
- for (i = 0; i < var_cnt; i++) {
- int j = i + consumed_xmm_halves;
+
+ for (i = 0; i < cnt; i++) {
+ j = i + consumed_xmm_halves;
if (j % 2)
- sparse_banks[i] = sse128_hi(hc->xmm[j / 2]);
+ data[i] = sse128_hi(hc->xmm[j / 2]);
else
- sparse_banks[i] = sse128_lo(hc->xmm[j / 2]);
+ data[i] = sse128_lo(hc->xmm[j / 2]);
}
return 0;
}

- return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks,
- var_cnt * sizeof(*sparse_banks));
+ return kvm_read_guest(kvm, hc->ingpa + offset, data,
+ cnt * sizeof(*data));
+}
+
+static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
+ u64 *sparse_banks, int consumed_xmm_halves,
+ gpa_t offset)
+{
+ if (hc->var_cnt > 64)
+ return -EINVAL;
+
+ /* Cap var_cnt to ignore banks that cannot contain a legal VP index. */
+ return kvm_hv_get_hc_data(kvm, hc, hc->var_cnt, KVM_HV_MAX_SPARSE_VCPU_SET_BITS,
+ sparse_banks, consumed_xmm_halves, offset);
}

static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu)
@@ -1895,7 +1908,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
if (!hc->var_cnt)
goto ret_success;

- if (kvm_get_sparse_vp_set(kvm, hc, 2, sparse_banks,
+ if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks, 2,
offsetof(struct hv_tlb_flush_ex,
hv_vp_set.bank_contents)))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
@@ -2006,7 +2019,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
if (!hc->var_cnt)
goto ret_success;

- if (kvm_get_sparse_vp_set(kvm, hc, 1, sparse_banks,
+ if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks, 1,
offsetof(struct hv_send_ipi_ex,
vp_set.bank_contents)))
return HV_STATUS_INVALID_HYPERCALL_INPUT;
--
2.37.3

2022-10-21 15:52:08

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 30/46] KVM: selftests: Better XMM read/write helpers

set_xmm()/get_xmm() helpers are fairly useless as they only read 64 bits
from 128-bit registers. Moreover, these helpers are not used. Borrow
_kvm_read_sse_reg()/_kvm_write_sse_reg() from KVM limiting them to
XMM0-XMM8 for now.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/processor.h | 70 ++++++++++---------
1 file changed, 36 insertions(+), 34 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index e8ca0d8a6a7e..dbd75717dc3b 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -436,71 +436,73 @@ static inline bool this_cpu_has(struct kvm_x86_cpu_feature feature)
return gprs[feature.reg] & BIT(feature.bit);
}

-#define SET_XMM(__var, __xmm) \
- asm volatile("movq %0, %%"#__xmm : : "r"(__var) : #__xmm)
+typedef u32 __attribute__((vector_size(16))) sse128_t;
+#define __sse128_u union { sse128_t vec; u64 as_u64[2]; u32 as_u32[4]; }
+#define sse128_lo(x) ({ __sse128_u t; t.vec = x; t.as_u64[0]; })
+#define sse128_hi(x) ({ __sse128_u t; t.vec = x; t.as_u64[1]; })

-static inline void set_xmm(int n, unsigned long val)
+static inline void read_sse_reg(int reg, sse128_t *data)
{
- switch (n) {
+ switch (reg) {
case 0:
- SET_XMM(val, xmm0);
+ asm("movdqa %%xmm0, %0" : "=m"(*data));
break;
case 1:
- SET_XMM(val, xmm1);
+ asm("movdqa %%xmm1, %0" : "=m"(*data));
break;
case 2:
- SET_XMM(val, xmm2);
+ asm("movdqa %%xmm2, %0" : "=m"(*data));
break;
case 3:
- SET_XMM(val, xmm3);
+ asm("movdqa %%xmm3, %0" : "=m"(*data));
break;
case 4:
- SET_XMM(val, xmm4);
+ asm("movdqa %%xmm4, %0" : "=m"(*data));
break;
case 5:
- SET_XMM(val, xmm5);
+ asm("movdqa %%xmm5, %0" : "=m"(*data));
break;
case 6:
- SET_XMM(val, xmm6);
+ asm("movdqa %%xmm6, %0" : "=m"(*data));
break;
case 7:
- SET_XMM(val, xmm7);
+ asm("movdqa %%xmm7, %0" : "=m"(*data));
break;
+ default:
+ BUG();
}
}

-#define GET_XMM(__xmm) \
-({ \
- unsigned long __val; \
- asm volatile("movq %%"#__xmm", %0" : "=r"(__val)); \
- __val; \
-})
-
-static inline unsigned long get_xmm(int n)
+static inline void write_sse_reg(int reg, const sse128_t *data)
{
- assert(n >= 0 && n <= 7);
-
- switch (n) {
+ switch (reg) {
case 0:
- return GET_XMM(xmm0);
+ asm("movdqa %0, %%xmm0" : : "m"(*data));
+ break;
case 1:
- return GET_XMM(xmm1);
+ asm("movdqa %0, %%xmm1" : : "m"(*data));
+ break;
case 2:
- return GET_XMM(xmm2);
+ asm("movdqa %0, %%xmm2" : : "m"(*data));
+ break;
case 3:
- return GET_XMM(xmm3);
+ asm("movdqa %0, %%xmm3" : : "m"(*data));
+ break;
case 4:
- return GET_XMM(xmm4);
+ asm("movdqa %0, %%xmm4" : : "m"(*data));
+ break;
case 5:
- return GET_XMM(xmm5);
+ asm("movdqa %0, %%xmm5" : : "m"(*data));
+ break;
case 6:
- return GET_XMM(xmm6);
+ asm("movdqa %0, %%xmm6" : : "m"(*data));
+ break;
case 7:
- return GET_XMM(xmm7);
+ asm("movdqa %0, %%xmm7" : : "m"(*data));
+ break;
+ default:
+ BUG();
}
-
- /* never reached */
- return 0;
}

static inline void cpu_relax(void)
--
2.37.3

2022-10-21 15:52:25

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 23/46] KVM: x86: hyper-v: L2 TLB flush

Handle L2 TLB flush requests by going through all vCPUs and checking
whether there are vCPUs running the same VM_ID with a VP_ID specified
in the requests. Perform synthetic exit to L2 upon finish.

Note, while checking VM_ID/VP_ID of running vCPUs seem to be a bit
racy, we count on the fact that KVM flushes the whole L2 VPID upon
transition. Also, KVM_REQ_HV_TLB_FLUSH request needs to be done upon
transition between L1 and L2 to make sure all pending requests are
always processed.

For the reference, Hyper-V TLFS refers to the feature as "Direct
Virtual Flush".

Note, nVMX/nSVM code does not handle VMCALL/VMMCALL from L2 yet.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 80 ++++++++++++++++++++++++++++++++++++-------
arch/x86/kvm/hyperv.h | 3 --
arch/x86/kvm/trace.h | 21 +++++++-----
3 files changed, 80 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 68a2200d4a6f..ec3051699d2a 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -34,6 +34,7 @@
#include <linux/eventfd.h>

#include <asm/apicdef.h>
+#include <asm/mshyperv.h>
#include <trace/events/kvm.h>

#include "trace.h"
@@ -1832,18 +1833,16 @@ static int kvm_hv_get_tlb_flush_entries(struct kvm *kvm, struct kvm_hv_hcall *hc
entries, consumed_xmm_halves, offset);
}

-static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu, u64 *entries, int count)
+static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo,
+ u64 *entries, int count)
{
- struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
u64 flush_all_entry = KVM_HV_TLB_FLUSHALL_ENTRY;

if (!hv_vcpu)
return;

- /* kvm_hv_flush_tlb() is not ready to handle requests for L2s yet */
- tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo[HV_L1_TLB_FLUSH_FIFO];
-
spin_lock(&tlb_flush_fifo->write_lock);

/*
@@ -1912,6 +1911,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
struct hv_tlb_flush_ex flush_ex;
struct hv_tlb_flush flush;
DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
+ struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
/*
* Normally, there can be no more than 'KVM_HV_TLB_FLUSH_FIFO_SIZE'
* entries on the TLB flush fifo. The last entry, however, needs to be
@@ -1955,7 +1955,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
}

trace_kvm_hv_flush_tlb(flush.processor_mask,
- flush.address_space, flush.flags);
+ flush.address_space, flush.flags,
+ is_guest_mode(vcpu));

valid_bank_mask = BIT_ULL(0);
sparse_banks[0] = flush.processor_mask;
@@ -1986,7 +1987,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
flush_ex.hv_vp_set.format,
flush_ex.address_space,
- flush_ex.flags);
+ flush_ex.flags, is_guest_mode(vcpu));

valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
all_cpus = flush_ex.hv_vp_set.format !=
@@ -2030,19 +2031,57 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
* vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't
* analyze it here, flush TLB regardless of the specified address space.
*/
- if (all_cpus) {
- kvm_for_each_vcpu(i, v, kvm)
- hv_tlb_flush_enqueue(v, tlb_flush_entries, hc->rep_cnt);
+ if (all_cpus && !is_guest_mode(vcpu)) {
+ kvm_for_each_vcpu(i, v, kvm) {
+ tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
+ hv_tlb_flush_enqueue(v, tlb_flush_fifo,
+ tlb_flush_entries, hc->rep_cnt);
+ }

kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
- } else {
+ } else if (!is_guest_mode(vcpu)) {
sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);

for_each_set_bit(i, vcpu_mask, KVM_MAX_VCPUS) {
v = kvm_get_vcpu(kvm, i);
if (!v)
continue;
- hv_tlb_flush_enqueue(v, tlb_flush_entries, hc->rep_cnt);
+ tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, false);
+ hv_tlb_flush_enqueue(v, tlb_flush_fifo,
+ tlb_flush_entries, hc->rep_cnt);
+ }
+
+ kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
+ } else {
+ struct kvm_vcpu_hv *hv_v;
+
+ bitmap_zero(vcpu_mask, KVM_MAX_VCPUS);
+
+ kvm_for_each_vcpu(i, v, kvm) {
+ hv_v = to_hv_vcpu(v);
+
+ /*
+ * The following check races with nested vCPUs entering/exiting
+ * and/or migrating between L1's vCPUs, however the only case when
+ * KVM *must* flush the TLB is when the target L2 vCPU keeps
+ * running on the same L1 vCPU from the moment of the request until
+ * kvm_hv_flush_tlb() returns. TLB is fully flushed in all other
+ * cases, e.g. when the target L2 vCPU migrates to a different L1
+ * vCPU or when the corresponding L1 vCPU temporary switches to a
+ * different L2 vCPU while the request is being processed.
+ */
+ if (!hv_v || hv_v->nested.vm_id != hv_vcpu->nested.vm_id)
+ continue;
+
+ if (!all_cpus &&
+ !hv_is_vp_in_sparse_set(hv_v->nested.vp_id, valid_bank_mask,
+ sparse_banks))
+ continue;
+
+ __set_bit(i, vcpu_mask);
+ tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(v, true);
+ hv_tlb_flush_enqueue(v, tlb_flush_fifo,
+ tlb_flush_entries, hc->rep_cnt);
}

kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
@@ -2232,10 +2271,25 @@ static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result)

static int kvm_hv_hypercall_complete(struct kvm_vcpu *vcpu, u64 result)
{
+ u32 tlb_lock_count = 0;
+ int ret;
+
+ if (hv_result_success(result) && is_guest_mode(vcpu) &&
+ kvm_hv_is_tlb_flush_hcall(vcpu) &&
+ kvm_read_guest(vcpu->kvm, to_hv_vcpu(vcpu)->nested.pa_page_gpa,
+ &tlb_lock_count, sizeof(tlb_lock_count)))
+ result = HV_STATUS_INVALID_HYPERCALL_INPUT;
+
trace_kvm_hv_hypercall_done(result);
kvm_hv_hypercall_set_result(vcpu, result);
++vcpu->stat.hypercalls;
- return kvm_skip_emulated_instruction(vcpu);
+
+ ret = kvm_skip_emulated_instruction(vcpu);
+
+ if (tlb_lock_count)
+ kvm_x86_ops.nested_ops->hv_inject_synthetic_vmexit_post_tlb_flush(vcpu);
+
+ return ret;
}

static int kvm_hv_hypercall_complete_userspace(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 5f9c76b45f46..7706e203ff43 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -159,9 +159,6 @@ static inline struct kvm_vcpu_hv_tlb_flush_fifo *kvm_hv_get_tlb_flush_fifo(struc
int i = is_guest_mode ? HV_L2_TLB_FLUSH_FIFO :
HV_L1_TLB_FLUSH_FIFO;

- /* KVM does not handle L2 TLB flush requests yet */
- WARN_ON_ONCE(i != HV_L1_TLB_FLUSH_FIFO);
-
return &hv_vcpu->tlb_flush_fifo[i];
}

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index bc25589ad588..09f3392dd830 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -1547,38 +1547,41 @@ TRACE_EVENT(kvm_hv_timer_state,
* Tracepoint for kvm_hv_flush_tlb.
*/
TRACE_EVENT(kvm_hv_flush_tlb,
- TP_PROTO(u64 processor_mask, u64 address_space, u64 flags),
- TP_ARGS(processor_mask, address_space, flags),
+ TP_PROTO(u64 processor_mask, u64 address_space, u64 flags, bool guest_mode),
+ TP_ARGS(processor_mask, address_space, flags, guest_mode),

TP_STRUCT__entry(
__field(u64, processor_mask)
__field(u64, address_space)
__field(u64, flags)
+ __field(bool, guest_mode)
),

TP_fast_assign(
__entry->processor_mask = processor_mask;
__entry->address_space = address_space;
__entry->flags = flags;
+ __entry->guest_mode = guest_mode;
),

- TP_printk("processor_mask 0x%llx address_space 0x%llx flags 0x%llx",
+ TP_printk("processor_mask 0x%llx address_space 0x%llx flags 0x%llx %s",
__entry->processor_mask, __entry->address_space,
- __entry->flags)
+ __entry->flags, __entry->guest_mode ? "(L2)" : "")
);

/*
* Tracepoint for kvm_hv_flush_tlb_ex.
*/
TRACE_EVENT(kvm_hv_flush_tlb_ex,
- TP_PROTO(u64 valid_bank_mask, u64 format, u64 address_space, u64 flags),
- TP_ARGS(valid_bank_mask, format, address_space, flags),
+ TP_PROTO(u64 valid_bank_mask, u64 format, u64 address_space, u64 flags, bool guest_mode),
+ TP_ARGS(valid_bank_mask, format, address_space, flags, guest_mode),

TP_STRUCT__entry(
__field(u64, valid_bank_mask)
__field(u64, format)
__field(u64, address_space)
__field(u64, flags)
+ __field(bool, guest_mode)
),

TP_fast_assign(
@@ -1586,12 +1589,14 @@ TRACE_EVENT(kvm_hv_flush_tlb_ex,
__entry->format = format;
__entry->address_space = address_space;
__entry->flags = flags;
+ __entry->guest_mode = guest_mode;
),

TP_printk("valid_bank_mask 0x%llx format 0x%llx "
- "address_space 0x%llx flags 0x%llx",
+ "address_space 0x%llx flags 0x%llx %s",
__entry->valid_bank_mask, __entry->format,
- __entry->address_space, __entry->flags)
+ __entry->address_space, __entry->flags,
+ __entry->guest_mode ? "(L2)" : "")
);

/*
--
2.37.3

2022-10-21 15:52:47

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 19/46] KVM: nVMX: Keep track of hv_vm_id/hv_vp_id when eVMCS is in use

To handle L2 TLB flush requests, KVM needs to keep track of L2's VM_ID/
VP_IDs which are set by L1 hypervisor. 'Partition assist page' address is
also needed to handle post-flush exit to L1 upon request.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 6 ++++++
arch/x86/kvm/vmx/nested.c | 15 +++++++++++++++
2 files changed, 21 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 5d590157266e..ede163b6f955 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -649,6 +649,12 @@ struct kvm_vcpu_hv {

/* Preallocated buffer for handling hypercalls passing sparse vCPU set */
u64 sparse_banks[HV_MAX_SPARSE_VCPU_BANKS];
+
+ struct {
+ u64 pa_page_gpa;
+ u64 vm_id;
+ u32 vp_id;
+ } nested;
};

/* Xen HVM per vcpu emulation context */
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index feab88a13026..7a4260416d88 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -224,6 +224,7 @@ static void vmx_disable_shadow_vmcs(struct vcpu_vmx *vmx)

static inline void nested_release_evmcs(struct kvm_vcpu *vcpu)
{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
struct vcpu_vmx *vmx = to_vmx(vcpu);

if (evmptr_is_valid(vmx->nested.hv_evmcs_vmptr)) {
@@ -232,6 +233,12 @@ static inline void nested_release_evmcs(struct kvm_vcpu *vcpu)
}

vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID;
+
+ if (hv_vcpu) {
+ hv_vcpu->nested.pa_page_gpa = INVALID_GPA;
+ hv_vcpu->nested.vm_id = 0;
+ hv_vcpu->nested.vp_id = 0;
+ }
}

static void vmx_sync_vmcs_host_state(struct vcpu_vmx *vmx,
@@ -1556,11 +1563,19 @@ static void copy_enlightened_to_vmcs12(struct vcpu_vmx *vmx, u32 hv_clean_fields
{
struct vmcs12 *vmcs12 = vmx->nested.cached_vmcs12;
struct hv_enlightened_vmcs *evmcs = vmx->nested.hv_evmcs;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(&vmx->vcpu);

/* HV_VMX_ENLIGHTENED_CLEAN_FIELD_NONE */
vmcs12->tpr_threshold = evmcs->tpr_threshold;
vmcs12->guest_rip = evmcs->guest_rip;

+ if (unlikely(!(hv_clean_fields &
+ HV_VMX_ENLIGHTENED_CLEAN_FIELD_ENLIGHTENMENTSCONTROL))) {
+ hv_vcpu->nested.pa_page_gpa = evmcs->partition_assist_page;
+ hv_vcpu->nested.vm_id = evmcs->hv_vm_id;
+ hv_vcpu->nested.vp_id = evmcs->hv_vp_id;
+ }
+
if (unlikely(!(hv_clean_fields &
HV_VMX_ENLIGHTENED_CLEAN_FIELD_GUEST_BASIC))) {
vmcs12->guest_rsp = evmcs->guest_rsp;
--
2.37.3

2022-10-21 15:54:02

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 42/46] KVM: selftests: Create a vendor independent helper to allocate Hyper-V specific test pages

There's no need to pollute VMX and SVM code with Hyper-V specific
stuff and allocate Hyper-V specific test pages for all test as only
few really need them. Create a dedicated struct and an allocation
helper.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/evmcs.h | 4 ++--
.../selftests/kvm/include/x86_64/hyperv.h | 15 +++++++++++++
.../selftests/kvm/include/x86_64/vmx.h | 8 -------
.../testing/selftests/kvm/lib/x86_64/hyperv.c | 20 +++++++++++++++++
tools/testing/selftests/kvm/lib/x86_64/vmx.c | 12 ----------
.../testing/selftests/kvm/x86_64/evmcs_test.c | 22 +++++++++----------
6 files changed, 48 insertions(+), 33 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/evmcs.h b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
index 59b60d45b8f6..94d6059e9a12 100644
--- a/tools/testing/selftests/kvm/include/x86_64/evmcs.h
+++ b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
@@ -256,9 +256,9 @@ static inline int evmcs_vmptrld(uint64_t vmcs_pa, void *vmcs)
return 0;
}

-static inline bool load_evmcs(uint64_t enlightened_vmcs_gpa, void *enlightened_vmcs)
+static inline bool load_evmcs(struct hyperv_test_pages *hv)
{
- if (evmcs_vmptrld(enlightened_vmcs_gpa, enlightened_vmcs))
+ if (evmcs_vmptrld(hv->enlightened_vmcs_gpa, hv->enlightened_vmcs))
return false;

current_evmcs->revision_id = EVMCS_VERSION;
diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index 3a17431c5771..186f3aab888f 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -267,4 +267,19 @@ extern struct hv_vp_assist_page *current_vp_assist;

int enable_vp_assist(uint64_t vp_assist_pa, void *vp_assist);

+struct hyperv_test_pages {
+ /* VP assist page */
+ void *vp_assist_hva;
+ uint64_t vp_assist_gpa;
+ void *vp_assist;
+
+ /* Enlightened VMCS */
+ void *enlightened_vmcs_hva;
+ uint64_t enlightened_vmcs_gpa;
+ void *enlightened_vmcs;
+};
+
+struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
+ vm_vaddr_t *p_hv_pages_gva);
+
#endif /* !SELFTEST_KVM_HYPERV_H */
diff --git a/tools/testing/selftests/kvm/include/x86_64/vmx.h b/tools/testing/selftests/kvm/include/x86_64/vmx.h
index 71b290b6469d..9e0ef83e7091 100644
--- a/tools/testing/selftests/kvm/include/x86_64/vmx.h
+++ b/tools/testing/selftests/kvm/include/x86_64/vmx.h
@@ -517,14 +517,6 @@ struct vmx_pages {
uint64_t vmwrite_gpa;
void *vmwrite;

- void *vp_assist_hva;
- uint64_t vp_assist_gpa;
- void *vp_assist;
-
- void *enlightened_vmcs_hva;
- uint64_t enlightened_vmcs_gpa;
- void *enlightened_vmcs;
-
void *eptp_hva;
uint64_t eptp_gpa;
void *eptp;
diff --git a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
index 32dc0afd9e5b..a2fc083c65ef 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
@@ -8,6 +8,26 @@
#include "processor.h"
#include "hyperv.h"

+struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
+ vm_vaddr_t *p_hv_pages_gva)
+{
+ vm_vaddr_t hv_pages_gva = vm_vaddr_alloc_page(vm);
+ struct hyperv_test_pages *hv = addr_gva2hva(vm, hv_pages_gva);
+
+ /* Setup of a region of guest memory for the VP Assist page. */
+ hv->vp_assist = (void *)vm_vaddr_alloc_page(vm);
+ hv->vp_assist_hva = addr_gva2hva(vm, (uintptr_t)hv->vp_assist);
+ hv->vp_assist_gpa = addr_gva2gpa(vm, (uintptr_t)hv->vp_assist);
+
+ /* Setup of a region of guest memory for the enlightened VMCS. */
+ hv->enlightened_vmcs = (void *)vm_vaddr_alloc_page(vm);
+ hv->enlightened_vmcs_hva = addr_gva2hva(vm, (uintptr_t)hv->enlightened_vmcs);
+ hv->enlightened_vmcs_gpa = addr_gva2gpa(vm, (uintptr_t)hv->enlightened_vmcs);
+
+ *p_hv_pages_gva = hv_pages_gva;
+ return hv;
+}
+
int enable_vp_assist(uint64_t vp_assist_pa, void *vp_assist)
{
uint64_t val = (vp_assist_pa & HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_MASK) |
diff --git a/tools/testing/selftests/kvm/lib/x86_64/vmx.c b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
index 40e4f427a3ec..de6571cd1065 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/vmx.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/vmx.c
@@ -109,18 +109,6 @@ vcpu_alloc_vmx(struct kvm_vm *vm, vm_vaddr_t *p_vmx_gva)
vmx->vmwrite_gpa = addr_gva2gpa(vm, (uintptr_t)vmx->vmwrite);
memset(vmx->vmwrite_hva, 0, getpagesize());

- /* Setup of a region of guest memory for the VP Assist page. */
- vmx->vp_assist = (void *)vm_vaddr_alloc_page(vm);
- vmx->vp_assist_hva = addr_gva2hva(vm, (uintptr_t)vmx->vp_assist);
- vmx->vp_assist_gpa = addr_gva2gpa(vm, (uintptr_t)vmx->vp_assist);
-
- /* Setup of a region of guest memory for the enlightened VMCS. */
- vmx->enlightened_vmcs = (void *)vm_vaddr_alloc_page(vm);
- vmx->enlightened_vmcs_hva =
- addr_gva2hva(vm, (uintptr_t)vmx->enlightened_vmcs);
- vmx->enlightened_vmcs_gpa =
- addr_gva2gpa(vm, (uintptr_t)vmx->enlightened_vmcs);
-
*p_vmx_gva = vmx_gva;
return vmx;
}
diff --git a/tools/testing/selftests/kvm/x86_64/evmcs_test.c b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
index 5a4c8b1873aa..74f076ba574b 100644
--- a/tools/testing/selftests/kvm/x86_64/evmcs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/evmcs_test.c
@@ -68,7 +68,7 @@ void l2_guest_code(void)
vmcall();
}

-void guest_code(struct vmx_pages *vmx_pages)
+void guest_code(struct vmx_pages *vmx_pages, struct hyperv_test_pages *hv_pages)
{
#define L2_GUEST_STACK_SIZE 64
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
@@ -78,23 +78,22 @@ void guest_code(struct vmx_pages *vmx_pages)
GUEST_SYNC(1);
GUEST_SYNC(2);

- enable_vp_assist(vmx_pages->vp_assist_gpa, vmx_pages->vp_assist);
+ enable_vp_assist(hv_pages->vp_assist_gpa, hv_pages->vp_assist);
evmcs_enable();

GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
GUEST_SYNC(3);
- GUEST_ASSERT(load_evmcs(vmx_pages->enlightened_vmcs_gpa,
- vmx_pages->enlightened_vmcs));
- GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa);
+ GUEST_ASSERT(load_evmcs(hv_pages));
+ GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);

GUEST_SYNC(4);
- GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa);
+ GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);

prepare_vmcs(vmx_pages, l2_guest_code,
&l2_guest_stack[L2_GUEST_STACK_SIZE]);

GUEST_SYNC(5);
- GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa);
+ GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);
current_evmcs->revision_id = -1u;
GUEST_ASSERT(vmlaunch());
current_evmcs->revision_id = EVMCS_VERSION;
@@ -104,7 +103,7 @@ void guest_code(struct vmx_pages *vmx_pages)
PIN_BASED_NMI_EXITING);

GUEST_ASSERT(!vmlaunch());
- GUEST_ASSERT(vmptrstz() == vmx_pages->enlightened_vmcs_gpa);
+ GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);

/*
* NMI forces L2->L1 exit, resuming L2 and hope that EVMCS is
@@ -152,7 +151,7 @@ void guest_code(struct vmx_pages *vmx_pages)
GUEST_SYNC(11);

/* Try enlightened vmptrld with an incorrect GPA */
- evmcs_vmptrld(0xdeadbeef, vmx_pages->enlightened_vmcs);
+ evmcs_vmptrld(0xdeadbeef, hv_pages->enlightened_vmcs);
GUEST_ASSERT(vmlaunch());
GUEST_ASSERT(ud_count == 1);
GUEST_DONE();
@@ -199,7 +198,7 @@ static struct kvm_vcpu *save_restore_vm(struct kvm_vm *vm,

int main(int argc, char *argv[])
{
- vm_vaddr_t vmx_pages_gva = 0;
+ vm_vaddr_t vmx_pages_gva = 0, hv_pages_gva = 0;

struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
@@ -217,7 +216,8 @@ int main(int argc, char *argv[])
vcpu_enable_evmcs(vcpu);

vcpu_alloc_vmx(vm, &vmx_pages_gva);
- vcpu_args_set(vcpu, 1, vmx_pages_gva);
+ vcpu_alloc_hyperv_test_pages(vm, &hv_pages_gva);
+ vcpu_args_set(vcpu, 2, vmx_pages_gva, hv_pages_gva);

vm_init_descriptor_tables(vm);
vcpu_init_descriptor_tables(vcpu);
--
2.37.3

2022-10-21 15:56:33

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 08/46] KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag

In preparation to implementing fine-grained Hyper-V TLB flush and
L2 TLB flush, resurrect dedicated KVM_REQ_HV_TLB_FLUSH request bit. As
KVM_REQ_TLB_FLUSH_GUEST is a stronger operation, clear KVM_REQ_HV_TLB_FLUSH
request in kvm_vcpu_flush_tlb_guest().

The flush itself is temporary handled by kvm_vcpu_flush_tlb_guest().

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/hyperv.c | 4 ++--
arch/x86/kvm/svm/svm.c | 7 +++++++
arch/x86/kvm/x86.c | 9 +++++++++
4 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 50fe0c7a5571..05d90e11e535 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -108,6 +108,8 @@
KVM_ARCH_REQ_FLAGS(30, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQ_MMU_FREE_OBSOLETE_ROOTS \
KVM_ARCH_REQ_FLAGS(31, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
+#define KVM_REQ_HV_TLB_FLUSH \
+ KVM_ARCH_REQ_FLAGS(32, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)

#define CR0_RESERVED_BITS \
(~(unsigned long)(X86_CR0_PE | X86_CR0_MP | X86_CR0_EM | X86_CR0_TS \
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 0adf4a437e85..3c0f639f6a05 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1870,11 +1870,11 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
* analyze it here, flush TLB regardless of the specified address space.
*/
if (all_cpus) {
- kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST);
+ kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
} else {
sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);

- kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST, vcpu_mask);
+ kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
}

ret_success:
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 58f0077d9357..9210a8840224 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3738,6 +3738,13 @@ static void svm_flush_tlb_current(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);

+ /*
+ * Unlike VMX, SVM doesn't provide a way to flush only NPT TLB entries.
+ * A TLB flush for the current ASID flushes both "host" and "guest" TLB
+ * entries, and thus is a superset of Hyper-V's fine grained flushing.
+ */
+ kvm_clear_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+
/*
* Flush only the current ASID even if the TLB flush was invoked via
* kvm_flush_remote_tlbs(). Although flushing remote TLBs requires all
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fdda5f447f87..bf2aa77b7a2f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3417,6 +3417,12 @@ static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu)
}

static_call(kvm_x86_flush_tlb_guest)(vcpu);
+
+ /*
+ * Flushing all "guest" TLB is always a superset of Hyper-V's fine
+ * grained flushing.
+ */
+ kvm_clear_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
}


@@ -10491,6 +10497,9 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)

kvm_service_local_tlb_flush_requests(vcpu);

+ if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu))
+ kvm_vcpu_flush_tlb_guest(vcpu);
+
if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) {
vcpu->run->exit_reason = KVM_EXIT_TPR_ACCESS;
r = 0;
--
2.37.3

2022-10-21 15:57:22

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 33/46] KVM: selftests: Hyper-V PV IPI selftest

Introduce a selftest for Hyper-V PV IPI hypercalls
(HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx).

The test creates one 'sender' vCPU and two 'receiver' vCPU and then
issues various combinations of send IPI hypercalls in both 'normal'
and 'fast' (with XMM input where necessary) mode. Later, the test
checks whether IPIs were delivered to the expected destination vCPU[s].

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/include/x86_64/hyperv.h | 35 +-
.../selftests/kvm/x86_64/hyperv_features.c | 2 +-
.../testing/selftests/kvm/x86_64/hyperv_ipi.c | 314 ++++++++++++++++++
5 files changed, 349 insertions(+), 4 deletions(-)
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_ipi.c

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 2f0d705db9db..83ea4740cf93 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -25,6 +25,7 @@
/x86_64/hyperv_clock
/x86_64/hyperv_cpuid
/x86_64/hyperv_features
+/x86_64/hyperv_ipi
/x86_64/hyperv_svm_test
/x86_64/max_vcpuid_cap_test
/x86_64/mmio_warning_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 0172eb6cb6ee..7cdb547c06db 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -86,6 +86,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/fix_hypercall_test
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_features
+TEST_GEN_PROGS_x86_64 += x86_64/hyperv_ipi
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_svm_test
TEST_GEN_PROGS_x86_64 += x86_64/kvm_clock_test
TEST_GEN_PROGS_x86_64 += x86_64/kvm_pv_test
diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index 40f8b1b423fc..d299064fe2b1 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -9,6 +9,8 @@
#ifndef SELFTEST_KVM_HYPERV_H
#define SELFTEST_KVM_HYPERV_H

+#include "processor.h"
+
#define HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS 0x40000000
#define HYPERV_CPUID_INTERFACE 0x40000001
#define HYPERV_CPUID_VERSION 0x40000002
@@ -184,10 +186,15 @@

/* hypercall options */
#define HV_HYPERCALL_FAST_BIT BIT(16)
+#define HV_HYPERCALL_VARHEAD_OFFSET 17

-static inline uint8_t hyperv_hypercall(u64 control, vm_vaddr_t input_address,
- vm_vaddr_t output_address,
- uint64_t *hv_status)
+/*
+ * Issue a Hyper-V hypercall. Returns exception vector raised or 0, 'hv_status'
+ * is set to the hypercall status (if no exception occurred).
+ */
+static inline uint8_t __hyperv_hypercall(u64 control, vm_vaddr_t input_address,
+ vm_vaddr_t output_address,
+ uint64_t *hv_status)
{
uint8_t vector;

@@ -203,6 +210,28 @@ static inline uint8_t hyperv_hypercall(u64 control, vm_vaddr_t input_address,
return vector;
}

+/* Issue a Hyper-V hypercall and assert that it succeeded. */
+static inline void hyperv_hypercall(u64 control, vm_vaddr_t input_address,
+ vm_vaddr_t output_address)
+{
+ uint64_t hv_status;
+ uint8_t vector;
+
+ vector = __hyperv_hypercall(control, input_address, output_address, &hv_status);
+
+ GUEST_ASSERT(!vector);
+ GUEST_ASSERT((hv_status & 0xffff) == 0);
+}
+
+/* Write 'Fast' hypercall input 'data' to the first 'n_sse_regs' SSE regs */
+static inline void hyperv_write_xmm_input(void *data, int n_sse_regs)
+{
+ int i;
+
+ for (i = 0; i < n_sse_regs; i++)
+ write_sse_reg(i, (sse128_t *)(data + sizeof(sse128_t) * i));
+}
+
/* Proper HV_X64_MSR_GUEST_OS_ID value */
#define HYPERV_LINUX_OS_ID ((u64)0x8100 << 48)

diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_features.c b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
index 5ff4ff2365bb..3163c3e8db0a 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_features.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
@@ -62,7 +62,7 @@ static void guest_hcall(vm_vaddr_t pgs_gpa, struct hcall_data *hcall)
input = output = 0;
}

- vector = hyperv_hypercall(hcall->control, input, output, &res);
+ vector = __hyperv_hypercall(hcall->control, input, output, &res);
if (hcall->ud_expected) {
GUEST_ASSERT_2(vector == UD_VECTOR, hcall->control, vector);
} else {
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c b/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
new file mode 100644
index 000000000000..8b791eac7d5a
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hyper-V HvCallSendSyntheticClusterIpi{,Ex} tests
+ *
+ * Copyright (C) 2022, Red Hat, Inc.
+ *
+ */
+
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <pthread.h>
+#include <inttypes.h>
+
+#include "kvm_util.h"
+#include "hyperv.h"
+#include "test_util.h"
+#include "vmx.h"
+
+#define RECEIVER_VCPU_ID_1 2
+#define RECEIVER_VCPU_ID_2 65
+
+#define IPI_VECTOR 0xfe
+
+static volatile uint64_t ipis_rcvd[RECEIVER_VCPU_ID_2 + 1];
+
+struct hv_vpset {
+ u64 format;
+ u64 valid_bank_mask;
+ u64 bank_contents[2];
+};
+
+enum HV_GENERIC_SET_FORMAT {
+ HV_GENERIC_SET_SPARSE_4K,
+ HV_GENERIC_SET_ALL,
+};
+
+/* HvCallSendSyntheticClusterIpi hypercall */
+struct hv_send_ipi {
+ u32 vector;
+ u32 reserved;
+ u64 cpu_mask;
+};
+
+/* HvCallSendSyntheticClusterIpiEx hypercall */
+struct hv_send_ipi_ex {
+ u32 vector;
+ u32 reserved;
+ struct hv_vpset vp_set;
+};
+
+static inline void hv_init(vm_vaddr_t pgs_gpa)
+{
+ wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
+ wrmsr(HV_X64_MSR_HYPERCALL, pgs_gpa);
+}
+
+static void receiver_code(void *hcall_page, vm_vaddr_t pgs_gpa)
+{
+ u32 vcpu_id;
+
+ x2apic_enable();
+ hv_init(pgs_gpa);
+
+ vcpu_id = rdmsr(HV_X64_MSR_VP_INDEX);
+
+ /* Signal sender vCPU we're ready */
+ ipis_rcvd[vcpu_id] = (u64)-1;
+
+ for (;;)
+ asm volatile("sti; hlt; cli");
+}
+
+static void guest_ipi_handler(struct ex_regs *regs)
+{
+ u32 vcpu_id = rdmsr(HV_X64_MSR_VP_INDEX);
+
+ ipis_rcvd[vcpu_id]++;
+ wrmsr(HV_X64_MSR_EOI, 1);
+}
+
+static inline void nop_loop(void)
+{
+ int i;
+
+ for (i = 0; i < 100000000; i++)
+ asm volatile("nop");
+}
+
+static void sender_guest_code(void *hcall_page, vm_vaddr_t pgs_gpa)
+{
+ struct hv_send_ipi *ipi = (struct hv_send_ipi *)hcall_page;
+ struct hv_send_ipi_ex *ipi_ex = (struct hv_send_ipi_ex *)hcall_page;
+ int stage = 1, ipis_expected[2] = {0};
+
+ hv_init(pgs_gpa);
+ GUEST_SYNC(stage++);
+
+ /* Wait for receiver vCPUs to come up */
+ while (!ipis_rcvd[RECEIVER_VCPU_ID_1] || !ipis_rcvd[RECEIVER_VCPU_ID_2])
+ nop_loop();
+ ipis_rcvd[RECEIVER_VCPU_ID_1] = ipis_rcvd[RECEIVER_VCPU_ID_2] = 0;
+
+ /* 'Slow' HvCallSendSyntheticClusterIpi to RECEIVER_VCPU_ID_1 */
+ ipi->vector = IPI_VECTOR;
+ ipi->cpu_mask = 1 << RECEIVER_VCPU_ID_1;
+ hyperv_hypercall(HVCALL_SEND_IPI, pgs_gpa, pgs_gpa + 4096);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ipis_expected[1]);
+ GUEST_SYNC(stage++);
+ /* 'Fast' HvCallSendSyntheticClusterIpi to RECEIVER_VCPU_ID_1 */
+ hyperv_hypercall(HVCALL_SEND_IPI | HV_HYPERCALL_FAST_BIT,
+ IPI_VECTOR, 1 << RECEIVER_VCPU_ID_1);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ipis_expected[1]);
+ GUEST_SYNC(stage++);
+
+ /* 'Slow' HvCallSendSyntheticClusterIpiEx to RECEIVER_VCPU_ID_1 */
+ memset(hcall_page, 0, 4096);
+ ipi_ex->vector = IPI_VECTOR;
+ ipi_ex->vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ ipi_ex->vp_set.valid_bank_mask = 1 << 0;
+ ipi_ex->vp_set.bank_contents[0] = BIT(RECEIVER_VCPU_ID_1);
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | (1 << HV_HYPERCALL_VARHEAD_OFFSET),
+ pgs_gpa, pgs_gpa + 4096);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ipis_expected[1]);
+ GUEST_SYNC(stage++);
+ /* 'XMM Fast' HvCallSendSyntheticClusterIpiEx to RECEIVER_VCPU_ID_1 */
+ hyperv_write_xmm_input(&ipi_ex->vp_set.valid_bank_mask, 1);
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | HV_HYPERCALL_FAST_BIT |
+ (1 << HV_HYPERCALL_VARHEAD_OFFSET),
+ IPI_VECTOR, HV_GENERIC_SET_SPARSE_4K);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ipis_expected[1]);
+ GUEST_SYNC(stage++);
+
+ /* 'Slow' HvCallSendSyntheticClusterIpiEx to RECEIVER_VCPU_ID_2 */
+ memset(hcall_page, 0, 4096);
+ ipi_ex->vector = IPI_VECTOR;
+ ipi_ex->vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ ipi_ex->vp_set.valid_bank_mask = 1 << 1;
+ ipi_ex->vp_set.bank_contents[0] = BIT(RECEIVER_VCPU_ID_2 - 64);
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | (1 << HV_HYPERCALL_VARHEAD_OFFSET),
+ pgs_gpa, pgs_gpa + 4096);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ++ipis_expected[1]);
+ GUEST_SYNC(stage++);
+ /* 'XMM Fast' HvCallSendSyntheticClusterIpiEx to RECEIVER_VCPU_ID_2 */
+ hyperv_write_xmm_input(&ipi_ex->vp_set.valid_bank_mask, 1);
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | HV_HYPERCALL_FAST_BIT |
+ (1 << HV_HYPERCALL_VARHEAD_OFFSET),
+ IPI_VECTOR, HV_GENERIC_SET_SPARSE_4K);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ++ipis_expected[1]);
+ GUEST_SYNC(stage++);
+
+ /* 'Slow' HvCallSendSyntheticClusterIpiEx to both RECEIVER_VCPU_ID_{1,2} */
+ memset(hcall_page, 0, 4096);
+ ipi_ex->vector = IPI_VECTOR;
+ ipi_ex->vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ ipi_ex->vp_set.valid_bank_mask = 1 << 1 | 1;
+ ipi_ex->vp_set.bank_contents[0] = BIT(RECEIVER_VCPU_ID_1);
+ ipi_ex->vp_set.bank_contents[1] = BIT(RECEIVER_VCPU_ID_2 - 64);
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | (2 << HV_HYPERCALL_VARHEAD_OFFSET),
+ pgs_gpa, pgs_gpa + 4096);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ++ipis_expected[1]);
+ GUEST_SYNC(stage++);
+ /* 'XMM Fast' HvCallSendSyntheticClusterIpiEx to both RECEIVER_VCPU_ID_{1, 2} */
+ hyperv_write_xmm_input(&ipi_ex->vp_set.valid_bank_mask, 2);
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | HV_HYPERCALL_FAST_BIT |
+ (2 << HV_HYPERCALL_VARHEAD_OFFSET),
+ IPI_VECTOR, HV_GENERIC_SET_SPARSE_4K);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ++ipis_expected[1]);
+ GUEST_SYNC(stage++);
+
+ /* 'Slow' HvCallSendSyntheticClusterIpiEx to HV_GENERIC_SET_ALL */
+ memset(hcall_page, 0, 4096);
+ ipi_ex->vector = IPI_VECTOR;
+ ipi_ex->vp_set.format = HV_GENERIC_SET_ALL;
+ hyperv_hypercall(HVCALL_SEND_IPI_EX, pgs_gpa, pgs_gpa + 4096);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ++ipis_expected[1]);
+ GUEST_SYNC(stage++);
+ /*
+ * 'XMM Fast' HvCallSendSyntheticClusterIpiEx to HV_GENERIC_SET_ALL.
+ * Nothing to write anything to XMM regs.
+ */
+ hyperv_hypercall(HVCALL_SEND_IPI_EX | HV_HYPERCALL_FAST_BIT,
+ IPI_VECTOR, HV_GENERIC_SET_ALL);
+ nop_loop();
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_1] == ++ipis_expected[0]);
+ GUEST_ASSERT(ipis_rcvd[RECEIVER_VCPU_ID_2] == ++ipis_expected[1]);
+ GUEST_SYNC(stage++);
+
+ GUEST_DONE();
+}
+
+static void *vcpu_thread(void *arg)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *)arg;
+ int old, r;
+
+ r = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old);
+ TEST_ASSERT(!r, "pthread_setcanceltype failed on vcpu_id=%u with errno=%d",
+ vcpu->id, r);
+
+ vcpu_run(vcpu);
+
+ TEST_FAIL("vCPU %u exited unexpectedly", vcpu->id);
+
+ return NULL;
+}
+
+static void cancel_join_vcpu_thread(pthread_t thread, struct kvm_vcpu *vcpu)
+{
+ void *retval;
+ int r;
+
+ r = pthread_cancel(thread);
+ TEST_ASSERT(!r, "pthread_cancel on vcpu_id=%d failed with errno=%d",
+ vcpu->id, r);
+
+ r = pthread_join(thread, &retval);
+ TEST_ASSERT(!r, "pthread_join on vcpu_id=%d failed with errno=%d",
+ vcpu->id, r);
+ TEST_ASSERT(retval == PTHREAD_CANCELED,
+ "expected retval=%p, got %p", PTHREAD_CANCELED,
+ retval);
+}
+
+int main(int argc, char *argv[])
+{
+ struct kvm_vm *vm;
+ struct kvm_vcpu *vcpu[3];
+ unsigned int exit_reason;
+ vm_vaddr_t hcall_page;
+ pthread_t threads[2];
+ int stage = 1, r;
+ struct ucall uc;
+
+ vm = vm_create_with_one_vcpu(&vcpu[0], sender_guest_code);
+
+ /* Hypercall input/output */
+ hcall_page = vm_vaddr_alloc_pages(vm, 2);
+ memset(addr_gva2hva(vm, hcall_page), 0x0, 2 * getpagesize());
+
+ vm_init_descriptor_tables(vm);
+
+ vcpu[1] = vm_vcpu_add(vm, RECEIVER_VCPU_ID_1, receiver_code);
+ vcpu_init_descriptor_tables(vcpu[1]);
+ vcpu_args_set(vcpu[1], 2, hcall_page, addr_gva2gpa(vm, hcall_page));
+ vcpu_set_msr(vcpu[1], HV_X64_MSR_VP_INDEX, RECEIVER_VCPU_ID_1);
+ vcpu_set_hv_cpuid(vcpu[1]);
+
+ vcpu[2] = vm_vcpu_add(vm, RECEIVER_VCPU_ID_2, receiver_code);
+ vcpu_init_descriptor_tables(vcpu[2]);
+ vcpu_args_set(vcpu[2], 2, hcall_page, addr_gva2gpa(vm, hcall_page));
+ vcpu_set_msr(vcpu[2], HV_X64_MSR_VP_INDEX, RECEIVER_VCPU_ID_2);
+ vcpu_set_hv_cpuid(vcpu[2]);
+
+ vm_install_exception_handler(vm, IPI_VECTOR, guest_ipi_handler);
+
+ vcpu_args_set(vcpu[0], 2, hcall_page, addr_gva2gpa(vm, hcall_page));
+ vcpu_set_hv_cpuid(vcpu[0]);
+
+ r = pthread_create(&threads[0], NULL, vcpu_thread, vcpu[1]);
+ TEST_ASSERT(!r, "pthread_create failed errno=%d", r);
+
+ r = pthread_create(&threads[1], NULL, vcpu_thread, vcpu[2]);
+ TEST_ASSERT(!r, "pthread_create failed errno=%d", errno);
+
+ while (true) {
+ vcpu_run(vcpu[0]);
+
+ exit_reason = vcpu[0]->run->exit_reason;
+ TEST_ASSERT(exit_reason == KVM_EXIT_IO,
+ "unexpected exit reason: %u (%s)",
+ exit_reason, exit_reason_str(exit_reason));
+
+ switch (get_ucall(vcpu[0], &uc)) {
+ case UCALL_SYNC:
+ TEST_ASSERT(uc.args[1] == stage,
+ "Unexpected stage: %ld (%d expected)\n",
+ uc.args[1], stage);
+ break;
+ case UCALL_DONE:
+ goto done;
+ case UCALL_ABORT:
+ REPORT_GUEST_ASSERT(uc);
+ /* NOT REACHED */
+ default:
+ TEST_FAIL("Unknown ucall %lu", uc.cmd);
+ }
+
+ stage++;
+ }
+
+done:
+ cancel_join_vcpu_thread(threads[0], vcpu[1]);
+ cancel_join_vcpu_thread(threads[1], vcpu[2]);
+ kvm_vm_free(vm);
+
+ return r;
+}
--
2.37.3

2022-10-21 15:57:34

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 35/46] KVM: selftests: Export vm_vaddr_unused_gap() to make it possible to request unmapped ranges

Currently, tests can only request a new vaddr range by using
vm_vaddr_alloc()/vm_vaddr_alloc_page()/vm_vaddr_alloc_pages() but
these functions allocate and map physical pages too. Make it possible
to request unmapped range too.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/include/kvm_util_base.h | 1 +
tools/testing/selftests/kvm/lib/kvm_util.c | 4 ++--
2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index e42a09cd24a0..a34bdf97bf7c 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -383,6 +383,7 @@ void vm_mem_region_set_flags(struct kvm_vm *vm, uint32_t slot, uint32_t flags);
void vm_mem_region_move(struct kvm_vm *vm, uint32_t slot, uint64_t new_gpa);
void vm_mem_region_delete(struct kvm_vm *vm, uint32_t slot);
struct kvm_vcpu *__vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id);
+vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min);
vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min);
vm_vaddr_t vm_vaddr_alloc_pages(struct kvm_vm *vm, int nr_pages);
vm_vaddr_t vm_vaddr_alloc_page(struct kvm_vm *vm);
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 29f743086ecc..fdb5836461ab 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1151,8 +1151,8 @@ struct kvm_vcpu *__vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id)
* TEST_ASSERT failure occurs for invalid input or no area of at least
* sz unallocated bytes >= vaddr_min is available.
*/
-static vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz,
- vm_vaddr_t vaddr_min)
+vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz,
+ vm_vaddr_t vaddr_min)
{
uint64_t pages = (sz + vm->page_size - 1) >> vm->page_shift;

--
2.37.3

2022-10-21 15:57:34

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 38/46] KVM: selftests: Sync 'struct hv_enlightened_vmcs' definition with hyperv-tlfs.h

'struct hv_enlightened_vmcs' definition in selftests is not '__packed'
and so we rely on the compiler doing the right padding. This is not
obvious so it seems beneficial to use the same definition as in kernel.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/include/x86_64/evmcs.h | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/evmcs.h b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
index 58db74f68af2..4b6840df2979 100644
--- a/tools/testing/selftests/kvm/include/x86_64/evmcs.h
+++ b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
@@ -41,6 +41,8 @@ struct hv_enlightened_vmcs {
u16 host_gs_selector;
u16 host_tr_selector;

+ u16 padding16_1;
+
u64 host_ia32_pat;
u64 host_ia32_efer;

@@ -159,7 +161,7 @@ struct hv_enlightened_vmcs {
u64 ept_pointer;

u16 virtual_processor_id;
- u16 padding16[3];
+ u16 padding16_2[3];

u64 padding64_2[5];
u64 guest_physical_address;
@@ -195,13 +197,13 @@ struct hv_enlightened_vmcs {
u64 guest_rip;

u32 hv_clean_fields;
- u32 hv_padding_32;
+ u32 padding32_1;
u32 hv_synthetic_controls;
struct {
u32 nested_flush_hypercall:1;
u32 msr_bitmap:1;
u32 reserved:30;
- } hv_enlightenments_control;
+ } __packed hv_enlightenments_control;
u32 hv_vp_id;
u32 padding32_2;
u64 hv_vm_id;
@@ -222,7 +224,7 @@ struct hv_enlightened_vmcs {
u64 host_ssp;
u64 host_ia32_int_ssp_table_addr;
u64 padding64_6;
-};
+} __packed;

#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_NONE 0
#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_IO_BITMAP BIT(0)
--
2.37.3

2022-10-21 15:57:58

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 17/46] KVM: x86: hyper-v: Create a separate fifo for L2 TLB flush

To handle L2 TLB flush requests, KVM needs to use a separate fifo from
regular (L1) Hyper-V TLB flush requests: e.g. when a request to flush
something in L2 is made, the target vCPU can transition from L2 to L1,
receive a request to flush a GVA for L1 and then try to enter L2 back.
The first request needs to be processed at this point. Similarly,
requests to flush GVAs in L1 must wait until L2 exits to L1.

No functional change as KVM doesn't handle L2 TLB flush requests from
L2 yet.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 8 +++++++-
arch/x86/kvm/hyperv.c | 11 +++++++----
arch/x86/kvm/hyperv.h | 19 ++++++++++++++++---
3 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f8ee72dd8660..6ebcf78368d1 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -612,6 +612,12 @@ struct kvm_vcpu_hv_synic {
*/
#define KVM_HV_TLB_FLUSHALL_ENTRY ((u64)-1)

+enum hv_tlb_flush_fifos {
+ HV_L1_TLB_FLUSH_FIFO,
+ HV_L2_TLB_FLUSH_FIFO,
+ HV_NR_TLB_FLUSH_FIFOS,
+};
+
struct kvm_vcpu_hv_tlb_flush_fifo {
spinlock_t write_lock;
DECLARE_KFIFO(entries, u64, KVM_HV_TLB_FLUSH_FIFO_SIZE);
@@ -639,7 +645,7 @@ struct kvm_vcpu_hv {
u32 nested_ebx; /* HYPERV_CPUID_NESTED_FEATURES.EBX */
} cpuid_cache;

- struct kvm_vcpu_hv_tlb_flush_fifo tlb_flush_fifo;
+ struct kvm_vcpu_hv_tlb_flush_fifo tlb_flush_fifo[HV_NR_TLB_FLUSH_FIFOS];
};

/* Xen HVM per vcpu emulation context */
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 1d1a65903eb5..56b725e852cb 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -956,8 +956,10 @@ int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)

hv_vcpu->vp_index = vcpu->vcpu_idx;

- INIT_KFIFO(hv_vcpu->tlb_flush_fifo.entries);
- spin_lock_init(&hv_vcpu->tlb_flush_fifo.write_lock);
+ for (i = 0; i < HV_NR_TLB_FLUSH_FIFOS; i++) {
+ INIT_KFIFO(hv_vcpu->tlb_flush_fifo[i].entries);
+ spin_lock_init(&hv_vcpu->tlb_flush_fifo[i].write_lock);
+ }

return 0;
}
@@ -1839,7 +1841,8 @@ static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu, u64 *entries, int count)
if (!hv_vcpu)
return;

- tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;
+ /* kvm_hv_flush_tlb() is not ready to handle requests for L2s yet */
+ tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo[HV_L1_TLB_FLUSH_FIFO];

spin_lock(&tlb_flush_fifo->write_lock);

@@ -1874,7 +1877,7 @@ int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
if (!tdp_enabled || !hv_vcpu)
return -EINVAL;

- tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;
+ tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(vcpu, is_guest_mode(vcpu));

count = kfifo_out(&tlb_flush_fifo->entries, entries, KVM_HV_TLB_FLUSH_FIFO_SIZE);

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index f79edf9234cd..8942e8c6c912 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -22,6 +22,7 @@
#define __ARCH_X86_KVM_HYPERV_H__

#include <linux/kvm_host.h>
+#include "x86.h"

/* "Hv#1" signature */
#define HYPERV_CPUID_SIGNATURE_EAX 0x31237648
@@ -151,15 +152,27 @@ int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args);
int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
struct kvm_cpuid_entry2 __user *entries);

+static inline struct kvm_vcpu_hv_tlb_flush_fifo *kvm_hv_get_tlb_flush_fifo(struct kvm_vcpu *vcpu,
+ bool is_guest_mode)
+{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ int i = is_guest_mode ? HV_L2_TLB_FLUSH_FIFO :
+ HV_L1_TLB_FLUSH_FIFO;
+
+ /* KVM does not handle L2 TLB flush requests yet */
+ WARN_ON_ONCE(i != HV_L1_TLB_FLUSH_FIFO);
+
+ return &hv_vcpu->tlb_flush_fifo[i];
+}
+
static inline void kvm_hv_vcpu_purge_flush_tlb(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
- struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);

- if (!hv_vcpu || !kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu))
+ if (!to_hv_vcpu(vcpu) || !kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu))
return;

- tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;
+ tlb_flush_fifo = kvm_hv_get_tlb_flush_fifo(vcpu, is_guest_mode(vcpu));

kfifo_reset_out(&tlb_flush_fifo->entries);
}
--
2.37.3

2022-10-21 15:58:09

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 20/46] KVM: nSVM: Keep track of Hyper-V hv_vm_id/hv_vp_id

Similar to nSVM, KVM needs to know L2's VM_ID/VP_ID and Partition
assist page address to handle L2 TLB flush requests.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/svm/hyperv.h | 15 +++++++++++++++
arch/x86/kvm/svm/nested.c | 2 ++
2 files changed, 17 insertions(+)

diff --git a/arch/x86/kvm/svm/hyperv.h b/arch/x86/kvm/svm/hyperv.h
index c59544cdf03b..e97d80974e72 100644
--- a/arch/x86/kvm/svm/hyperv.h
+++ b/arch/x86/kvm/svm/hyperv.h
@@ -9,5 +9,20 @@
#include <asm/mshyperv.h>

#include "../hyperv.h"
+#include "svm.h"
+
+static inline void nested_svm_hv_update_vm_vp_ids(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_svm *svm = to_svm(vcpu);
+ struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+
+ if (!hv_vcpu)
+ return;
+
+ hv_vcpu->nested.pa_page_gpa = hve->partition_assist_page;
+ hv_vcpu->nested.vm_id = hve->hv_vm_id;
+ hv_vcpu->nested.vp_id = hve->hv_vp_id;
+}

#endif /* __ARCH_X86_KVM_SVM_HYPERV_H__ */
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index c2a49aa50a58..45bab740f3f0 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -799,6 +799,8 @@ int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa,
if (kvm_vcpu_apicv_active(vcpu))
kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);

+ nested_svm_hv_update_vm_vp_ids(vcpu);
+
return 0;
}

--
2.37.3

2022-10-21 16:00:08

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 36/46] KVM: selftests: Drop helpers to read/write page table entries

From: Sean Christopherson <[email protected]>

Drop vm_{g,s}et_page_table_entry() and instead expose the "inner"
helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the
PTE, i.e. let tests directly modify PTEs instead of bouncing through
helpers that just make life difficult.

Opportunsitically use BIT_ULL() in emulator_error_test, and use the
MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the
same value.

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
---
.../selftests/kvm/include/x86_64/processor.h | 6 ++----
.../selftests/kvm/lib/x86_64/processor.c | 21 ++-----------------
.../kvm/x86_64/emulator_error_test.c | 6 ++++--
3 files changed, 8 insertions(+), 25 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index dbd75717dc3b..f21d933a2663 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -829,10 +829,8 @@ static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val)

bool kvm_is_tdp_enabled(void);

-uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr);
-void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr, uint64_t pte);
+uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
+ uint64_t vaddr);

uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
uint64_t a3);
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 39c4409ef56a..90b35998b0f3 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -241,9 +241,8 @@ void virt_map_level(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
}
}

-static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm,
- struct kvm_vcpu *vcpu,
- uint64_t vaddr)
+uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
+ uint64_t vaddr)
{
uint16_t index[4];
uint64_t *pml4e, *pdpe, *pde;
@@ -313,22 +312,6 @@ static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm,
return &pte[index[0]];
}

-uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr)
-{
- uint64_t *pte = _vm_get_page_table_entry(vm, vcpu, vaddr);
-
- return *(uint64_t *)pte;
-}
-
-void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr, uint64_t pte)
-{
- uint64_t *new_pte = _vm_get_page_table_entry(vm, vcpu, vaddr);
-
- *(uint64_t *)new_pte = pte;
-}
-
void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
{
uint64_t *pml4e, *pml4e_start;
diff --git a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
index 236e11755ba6..bde247f3c8a1 100644
--- a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
+++ b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
@@ -152,8 +152,9 @@ int main(int argc, char *argv[])
{
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
- uint64_t gpa, pte;
+ uint64_t *pte;
uint64_t *hva;
+ uint64_t gpa;
int rc;

/* Tell stdout not to buffer its content */
@@ -178,8 +179,9 @@ int main(int argc, char *argv[])
virt_map(vm, MEM_REGION_GVA, MEM_REGION_GPA, 1);
hva = addr_gpa2hva(vm, MEM_REGION_GPA);
memset(hva, 0, PAGE_SIZE);
+
pte = vm_get_page_table_entry(vm, vcpu, MEM_REGION_GVA);
- vm_set_page_table_entry(vm, vcpu, MEM_REGION_GVA, pte | (1ull << 36));
+ *pte |= BIT_ULL(MAXPHYADDR);

vcpu_run(vcpu);
process_exit_on_emulation_error(vcpu);
--
2.37.3

2022-10-21 16:00:55

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 34/46] KVM: selftests: Fill in vm->vpages_mapped bitmap in virt_map() too

Similar to vm_vaddr_alloc(), virt_map() needs to reflect the mapping
in vm->vpages_mapped.

While on it, remove unneeded code wraping in vm_vaddr_alloc().

Reviewed-by: Andrew Jones <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/lib/kvm_util.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 3578b9a7cc2f..29f743086ecc 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1256,8 +1256,7 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min)

virt_pg_map(vm, vaddr, paddr);

- sparsebit_set(vm->vpages_mapped,
- vaddr >> vm->page_shift);
+ sparsebit_set(vm->vpages_mapped, vaddr >> vm->page_shift);
}

return vaddr_start;
@@ -1330,6 +1329,8 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
virt_pg_map(vm, vaddr, paddr);
vaddr += page_size;
paddr += page_size;
+
+ sparsebit_set(vm->vpages_mapped, vaddr >> vm->page_shift);
}
}

--
2.37.3

2022-10-21 16:01:21

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 31/46] KVM: selftests: Move HYPERV_LINUX_OS_ID definition to a common header

HYPERV_LINUX_OS_ID needs to be written to HV_X64_MSR_GUEST_OS_ID by
each Hyper-V specific selftest.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/include/x86_64/hyperv.h | 3 +++
tools/testing/selftests/kvm/x86_64/hyperv_features.c | 6 ++----
2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index b66910702c0a..f0a8a93694b2 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -185,4 +185,7 @@
/* hypercall options */
#define HV_HYPERCALL_FAST_BIT BIT(16)

+/* Proper HV_X64_MSR_GUEST_OS_ID value */
+#define HYPERV_LINUX_OS_ID ((u64)0x8100 << 48)
+
#endif /* !SELFTEST_KVM_HYPERV_H */
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_features.c b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
index 05b32e550a80..71bb91602a7f 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_features.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
@@ -13,8 +13,6 @@
#include "processor.h"
#include "hyperv.h"

-#define LINUX_OS_ID ((u64)0x8100 << 48)
-
static inline uint8_t hypercall(u64 control, vm_vaddr_t input_address,
vm_vaddr_t output_address, uint64_t *hv_status)
{
@@ -71,7 +69,7 @@ static void guest_hcall(vm_vaddr_t pgs_gpa, struct hcall_data *hcall)

GUEST_ASSERT(hcall->control);

- wrmsr(HV_X64_MSR_GUEST_OS_ID, LINUX_OS_ID);
+ wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
wrmsr(HV_X64_MSR_HYPERCALL, pgs_gpa);

if (!(hcall->control & HV_HYPERCALL_FAST_BIT)) {
@@ -169,7 +167,7 @@ static void guest_test_msrs_access(void)
*/
msr->idx = HV_X64_MSR_GUEST_OS_ID;
msr->write = 1;
- msr->write_val = LINUX_OS_ID;
+ msr->write_val = HYPERV_LINUX_OS_ID;
msr->available = 1;
break;
case 3:
--
2.37.3

2022-10-21 16:02:56

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 18/46] KVM: x86: hyper-v: Use preallocated buffer in 'struct kvm_vcpu_hv' instead of on-stack 'sparse_banks'

To make kvm_hv_flush_tlb() ready to handle L2 TLB flush requests, KVM needs
to allow for all 64 sparse vCPU banks regardless of KVM_MAX_VCPUs as L1
may use vCPU overcommit for L2. To avoid growing on-stack allocation, make
'sparse_banks' part of per-vCPU 'struct kvm_vcpu_hv' which is allocated
dynamically.

Note: sparse_set_to_vcpu_mask() can't currently be used to handle L2
requests as KVM does not keep L2 VM_ID -> L2 VCPU_ID -> L1 vCPU mappings,
i.e. its vp_bitmap array is still bounded by the number of L1 vCPUs and so
can remain an on-stack allocation.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 3 +++
arch/x86/kvm/hyperv.c | 6 ++++--
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 6ebcf78368d1..5d590157266e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -646,6 +646,9 @@ struct kvm_vcpu_hv {
} cpuid_cache;

struct kvm_vcpu_hv_tlb_flush_fifo tlb_flush_fifo[HV_NR_TLB_FLUSH_FIFOS];
+
+ /* Preallocated buffer for handling hypercalls passing sparse vCPU set */
+ u64 sparse_banks[HV_MAX_SPARSE_VCPU_BANKS];
};

/* Xen HVM per vcpu emulation context */
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 56b725e852cb..68a2200d4a6f 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1906,6 +1906,8 @@ int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)

static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ u64 *sparse_banks = hv_vcpu->sparse_banks;
struct kvm *kvm = vcpu->kvm;
struct hv_tlb_flush_ex flush_ex;
struct hv_tlb_flush flush;
@@ -1919,7 +1921,6 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
u64 __tlb_flush_entries[KVM_HV_TLB_FLUSH_FIFO_SIZE - 1];
u64 *tlb_flush_entries;
u64 valid_bank_mask;
- u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
struct kvm_vcpu *v;
unsigned long i;
bool all_cpus;
@@ -2076,11 +2077,12 @@ static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,

static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ u64 *sparse_banks = hv_vcpu->sparse_banks;
struct kvm *kvm = vcpu->kvm;
struct hv_send_ipi_ex send_ipi_ex;
struct hv_send_ipi send_ipi;
u64 valid_bank_mask;
- u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
u32 vector;
bool all_cpus;

--
2.37.3

2022-10-21 16:02:56

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 37/46] KVM: selftests: Hyper-V PV TLB flush selftest

Introduce a selftest for Hyper-V PV TLB flush hypercalls
(HvFlushVirtualAddressSpace/HvFlushVirtualAddressSpaceEx,
HvFlushVirtualAddressList/HvFlushVirtualAddressListEx).

The test creates one 'sender' vCPU and two 'worker' vCPU which do busy
loop reading from a certain GVA checking the observed value. Sender
vCPU swaos the data page with another page filled with a different value.
The expectation for workers is also altered. Without TLB flush on worker
vCPUs, they may continue to observe old value. To guard against accidental
TLB flushes for worker vCPUs the test is repeated 100 times.

Hyper-V TLB flush hypercalls are tested in both 'normal' and 'XMM
fast' modes.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/include/x86_64/hyperv.h | 1 +
.../selftests/kvm/x86_64/hyperv_tlb_flush.c | 690 ++++++++++++++++++
4 files changed, 693 insertions(+)
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 83ea4740cf93..68d3d2080b59 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -27,6 +27,7 @@
/x86_64/hyperv_features
/x86_64/hyperv_ipi
/x86_64/hyperv_svm_test
+/x86_64/hyperv_tlb_flush
/x86_64/max_vcpuid_cap_test
/x86_64/mmio_warning_test
/x86_64/monitor_mwait_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 7cdb547c06db..c4342dd427a2 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -88,6 +88,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_features
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_ipi
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_svm_test
+TEST_GEN_PROGS_x86_64 += x86_64/hyperv_tlb_flush
TEST_GEN_PROGS_x86_64 += x86_64/kvm_clock_test
TEST_GEN_PROGS_x86_64 += x86_64/kvm_pv_test
TEST_GEN_PROGS_x86_64 += x86_64/mmio_warning_test
diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index d299064fe2b1..e2cda9f9f409 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -187,6 +187,7 @@
/* hypercall options */
#define HV_HYPERCALL_FAST_BIT BIT(16)
#define HV_HYPERCALL_VARHEAD_OFFSET 17
+#define HV_HYPERCALL_REP_COMP_OFFSET 32

/*
* Issue a Hyper-V hypercall. Returns exception vector raised or 0, 'hv_status'
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c b/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c
new file mode 100644
index 000000000000..44525255f5c8
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c
@@ -0,0 +1,690 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hyper-V HvFlushVirtualAddress{List,Space}{,Ex} tests
+ *
+ * Copyright (C) 2022, Red Hat, Inc.
+ *
+ */
+
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <asm/barrier.h>
+#include <pthread.h>
+#include <inttypes.h>
+
+#include "kvm_util.h"
+#include "processor.h"
+#include "hyperv.h"
+#include "test_util.h"
+#include "vmx.h"
+
+#define WORKER_VCPU_ID_1 2
+#define WORKER_VCPU_ID_2 65
+
+#define NTRY 100
+#define NTEST_PAGES 2
+
+struct hv_vpset {
+ u64 format;
+ u64 valid_bank_mask;
+ u64 bank_contents[];
+};
+
+enum HV_GENERIC_SET_FORMAT {
+ HV_GENERIC_SET_SPARSE_4K,
+ HV_GENERIC_SET_ALL,
+};
+
+#define HV_FLUSH_ALL_PROCESSORS BIT(0)
+#define HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES BIT(1)
+#define HV_FLUSH_NON_GLOBAL_MAPPINGS_ONLY BIT(2)
+#define HV_FLUSH_USE_EXTENDED_RANGE_FORMAT BIT(3)
+
+/* HvFlushVirtualAddressSpace, HvFlushVirtualAddressList hypercalls */
+struct hv_tlb_flush {
+ u64 address_space;
+ u64 flags;
+ u64 processor_mask;
+ u64 gva_list[];
+} __packed;
+
+/* HvFlushVirtualAddressSpaceEx, HvFlushVirtualAddressListEx hypercalls */
+struct hv_tlb_flush_ex {
+ u64 address_space;
+ u64 flags;
+ struct hv_vpset hv_vp_set;
+ u64 gva_list[];
+} __packed;
+
+/*
+ * Pass the following info to 'workers' and 'sender'
+ * - Hypercall page's GVA
+ * - Hypercall page's GPA
+ * - Test pages GVA
+ * - GVAs of the test pages' PTEs
+ */
+struct test_data {
+ vm_vaddr_t hcall_gva;
+ vm_paddr_t hcall_gpa;
+ vm_vaddr_t test_pages;
+ vm_vaddr_t test_pages_pte[NTEST_PAGES];
+};
+
+/* 'Worker' vCPU code checking the contents of the test page */
+static void worker_guest_code(vm_vaddr_t test_data)
+{
+ struct test_data *data = (struct test_data *)test_data;
+ u32 vcpu_id = rdmsr(HV_X64_MSR_VP_INDEX);
+ void *exp_page = (void *)data->test_pages + PAGE_SIZE * NTEST_PAGES;
+ u64 *this_cpu = (u64 *)(exp_page + vcpu_id * sizeof(u64));
+ u64 expected, val;
+
+ x2apic_enable();
+ wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
+
+ for (;;) {
+ cpu_relax();
+
+ expected = READ_ONCE(*this_cpu);
+
+ /*
+ * Make sure the value in the test page is read after reading
+ * the expectation for the first time. Pairs with wmb() in
+ * prepare_to_test().
+ */
+ rmb();
+
+ val = READ_ONCE(*(u64 *)data->test_pages);
+
+ /*
+ * Make sure the value in the test page is read after before
+ * reading the expectation for the second time. Pairs with wmb()
+ * post_test().
+ */
+ rmb();
+
+ /*
+ * '0' indicates the sender is between iterations, wait until
+ * the sender is ready for this vCPU to start checking again.
+ */
+ if (!expected)
+ continue;
+
+ /*
+ * Re-read the per-vCPU byte to ensure the sender didn't move
+ * onto a new iteration.
+ */
+ if (expected != READ_ONCE(*this_cpu))
+ continue;
+
+ GUEST_ASSERT(val == expected);
+ }
+}
+
+/*
+ * Write per-CPU info indicating what each 'worker' CPU is supposed to see in
+ * test page. '0' means don't check.
+ */
+static void set_expected_val(void *addr, u64 val, int vcpu_id)
+{
+ void *exp_page = addr + PAGE_SIZE * NTEST_PAGES;
+
+ *(u64 *)(exp_page + vcpu_id * sizeof(u64)) = val;
+}
+
+/*
+ * Update PTEs swapping two test pages.
+ * TODO: use swap()/xchg() when these are provided.
+ */
+static void swap_two_test_pages(vm_paddr_t pte_gva1, vm_paddr_t pte_gva2)
+{
+ uint64_t tmp = *(uint64_t *)pte_gva1;
+
+ *(uint64_t *)pte_gva1 = *(uint64_t *)pte_gva2;
+ *(uint64_t *)pte_gva2 = tmp;
+}
+
+/*
+ * TODO: replace the silly NOP loop with a proper udelay() implementation.
+ */
+static inline void do_delay(void)
+{
+ int i;
+
+ for (i = 0; i < 1000000; i++)
+ asm volatile("nop");
+}
+
+/*
+ * Prepare to test: 'disable' workers by setting the expectation to '0',
+ * clear hypercall input page and then swap two test pages.
+ */
+static inline void prepare_to_test(struct test_data *data)
+{
+ /* Clear hypercall input page */
+ memset((void *)data->hcall_gva, 0, PAGE_SIZE);
+
+ /* 'Disable' workers */
+ set_expected_val((void *)data->test_pages, 0x0, WORKER_VCPU_ID_1);
+ set_expected_val((void *)data->test_pages, 0x0, WORKER_VCPU_ID_2);
+
+ /* Make sure workers are 'disabled' before we swap PTEs. */
+ wmb();
+
+ /* Make sure workers have enough time to notice */
+ do_delay();
+
+ /* Swap test page mappings */
+ swap_two_test_pages(data->test_pages_pte[0], data->test_pages_pte[1]);
+}
+
+/*
+ * Finalize the test: check hypercall resule set the expected val for
+ * 'worker' CPUs and give them some time to test.
+ */
+static inline void post_test(struct test_data *data, u64 exp1, u64 exp2)
+{
+ /* Make sure we change the expectation after swapping PTEs */
+ wmb();
+
+ /* Set the expectation for workers, '0' means don't test */
+ set_expected_val((void *)data->test_pages, exp1, WORKER_VCPU_ID_1);
+ set_expected_val((void *)data->test_pages, exp2, WORKER_VCPU_ID_2);
+
+ /* Make sure workers have enough time to test */
+ do_delay();
+}
+
+#define TESTVAL1 0x0101010101010101
+#define TESTVAL2 0x0202020202020202
+
+/* Main vCPU doing the test */
+static void sender_guest_code(vm_vaddr_t test_data)
+{
+ struct test_data *data = (struct test_data *)test_data;
+ struct hv_tlb_flush *flush = (struct hv_tlb_flush *)data->hcall_gva;
+ struct hv_tlb_flush_ex *flush_ex = (struct hv_tlb_flush_ex *)data->hcall_gva;
+ vm_paddr_t hcall_gpa = data->hcall_gpa;
+ int i, stage = 1;
+
+ wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
+ wrmsr(HV_X64_MSR_HYPERCALL, data->hcall_gpa);
+
+ /* "Slow" hypercalls */
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE for WORKER_VCPU_ID_1 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush->processor_mask = BIT(WORKER_VCPU_ID_1);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE, hcall_gpa,
+ hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2, 0x0);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST for WORKER_VCPU_ID_1 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush->processor_mask = BIT(WORKER_VCPU_ID_1);
+ flush->gva_list[0] = (u64)data->test_pages;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2, 0x0);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE for HV_FLUSH_ALL_PROCESSORS */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
+ HV_FLUSH_ALL_PROCESSORS;
+ flush->processor_mask = 0;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE, hcall_gpa,
+ hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2, i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST for HV_FLUSH_ALL_PROCESSORS */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
+ HV_FLUSH_ALL_PROCESSORS;
+ flush->gva_list[0] = (u64)data->test_pages;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX for WORKER_VCPU_ID_2 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_2 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX |
+ (1 << HV_HYPERCALL_VARHEAD_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, 0x0, i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX for WORKER_VCPU_ID_2 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_2 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ /* bank_contents and gva_list occupy the same space, thus [1] */
+ flush_ex->gva_list[1] = (u64)data->test_pages;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX |
+ (1 << HV_HYPERCALL_VARHEAD_OFFSET) |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, 0x0, i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX for both vCPUs */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_2 / 64) |
+ BIT_ULL(WORKER_VCPU_ID_1 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_1 % 64);
+ flush_ex->hv_vp_set.bank_contents[1] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX |
+ (2 << HV_HYPERCALL_VARHEAD_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX for both vCPUs */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_1 / 64) |
+ BIT_ULL(WORKER_VCPU_ID_2 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_1 % 64);
+ flush_ex->hv_vp_set.bank_contents[1] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ /* bank_contents and gva_list occupy the same space, thus [2] */
+ flush_ex->gva_list[2] = (u64)data->test_pages;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX |
+ (2 << HV_HYPERCALL_VARHEAD_OFFSET) |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX for HV_GENERIC_SET_ALL */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_ALL;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX,
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX for HV_GENERIC_SET_ALL */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_ALL;
+ flush_ex->gva_list[0] = (u64)data->test_pages;
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ hcall_gpa, hcall_gpa + PAGE_SIZE);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ /* "Fast" hypercalls */
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE for WORKER_VCPU_ID_1 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->processor_mask = BIT(WORKER_VCPU_ID_1);
+ hyperv_write_xmm_input(&flush->processor_mask, 1);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE |
+ HV_HYPERCALL_FAST_BIT, 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2, 0x0);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST for WORKER_VCPU_ID_1 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->processor_mask = BIT(WORKER_VCPU_ID_1);
+ flush->gva_list[0] = (u64)data->test_pages;
+ hyperv_write_xmm_input(&flush->processor_mask, 1);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST |
+ HV_HYPERCALL_FAST_BIT |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2, 0x0);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE for HV_FLUSH_ALL_PROCESSORS */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ hyperv_write_xmm_input(&flush->processor_mask, 1);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE |
+ HV_HYPERCALL_FAST_BIT, 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
+ HV_FLUSH_ALL_PROCESSORS);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST for HV_FLUSH_ALL_PROCESSORS */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush->gva_list[0] = (u64)data->test_pages;
+ hyperv_write_xmm_input(&flush->processor_mask, 1);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST |
+ HV_HYPERCALL_FAST_BIT |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET), 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
+ HV_FLUSH_ALL_PROCESSORS);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX for WORKER_VCPU_ID_2 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_2 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ hyperv_write_xmm_input(&flush_ex->hv_vp_set, 2);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX |
+ HV_HYPERCALL_FAST_BIT |
+ (1 << HV_HYPERCALL_VARHEAD_OFFSET),
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, 0x0, i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX for WORKER_VCPU_ID_2 */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_2 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ /* bank_contents and gva_list occupy the same space, thus [1] */
+ flush_ex->gva_list[1] = (u64)data->test_pages;
+ hyperv_write_xmm_input(&flush_ex->hv_vp_set, 2);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX |
+ HV_HYPERCALL_FAST_BIT |
+ (1 << HV_HYPERCALL_VARHEAD_OFFSET) |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, 0x0, i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX for both vCPUs */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_2 / 64) |
+ BIT_ULL(WORKER_VCPU_ID_1 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_1 % 64);
+ flush_ex->hv_vp_set.bank_contents[1] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ hyperv_write_xmm_input(&flush_ex->hv_vp_set, 2);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX |
+ HV_HYPERCALL_FAST_BIT |
+ (2 << HV_HYPERCALL_VARHEAD_OFFSET),
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, i % 2 ? TESTVAL1 :
+ TESTVAL2, i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX for both vCPUs */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ flush_ex->hv_vp_set.valid_bank_mask = BIT_ULL(WORKER_VCPU_ID_1 / 64) |
+ BIT_ULL(WORKER_VCPU_ID_2 / 64);
+ flush_ex->hv_vp_set.bank_contents[0] = BIT_ULL(WORKER_VCPU_ID_1 % 64);
+ flush_ex->hv_vp_set.bank_contents[1] = BIT_ULL(WORKER_VCPU_ID_2 % 64);
+ /* bank_contents and gva_list occupy the same space, thus [2] */
+ flush_ex->gva_list[2] = (u64)data->test_pages;
+ hyperv_write_xmm_input(&flush_ex->hv_vp_set, 3);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX |
+ HV_HYPERCALL_FAST_BIT |
+ (2 << HV_HYPERCALL_VARHEAD_OFFSET) |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX for HV_GENERIC_SET_ALL */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_ALL;
+ hyperv_write_xmm_input(&flush_ex->hv_vp_set, 2);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX |
+ HV_HYPERCALL_FAST_BIT,
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_SYNC(stage++);
+
+ /* HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX for HV_GENERIC_SET_ALL */
+ for (i = 0; i < NTRY; i++) {
+ prepare_to_test(data);
+ flush_ex->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ flush_ex->hv_vp_set.format = HV_GENERIC_SET_ALL;
+ flush_ex->gva_list[0] = (u64)data->test_pages;
+ hyperv_write_xmm_input(&flush_ex->hv_vp_set, 2);
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX |
+ HV_HYPERCALL_FAST_BIT |
+ (1UL << HV_HYPERCALL_REP_COMP_OFFSET),
+ 0x0, HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES);
+ post_test(data, i % 2 ? TESTVAL1 : TESTVAL2,
+ i % 2 ? TESTVAL1 : TESTVAL2);
+ }
+
+ GUEST_DONE();
+}
+
+static void *vcpu_thread(void *arg)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *)arg;
+ struct ucall uc;
+ int old;
+ int r;
+ unsigned int exit_reason;
+
+ r = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &old);
+ TEST_ASSERT(!r, "pthread_setcanceltype failed on vcpu_id=%u with errno=%d",
+ vcpu->id, r);
+
+ vcpu_run(vcpu);
+ exit_reason = vcpu->run->exit_reason;
+
+ TEST_ASSERT(exit_reason == KVM_EXIT_IO,
+ "vCPU %u exited with unexpected exit reason %u-%s, expected KVM_EXIT_IO",
+ vcpu->id, exit_reason, exit_reason_str(exit_reason));
+
+ switch (get_ucall(vcpu, &uc)) {
+ case UCALL_ABORT:
+ REPORT_GUEST_ASSERT(uc);
+ /* NOT REACHED */
+ default:
+ TEST_FAIL("Unexpected ucall %lu, vCPU %d", uc.cmd, vcpu->id);
+ }
+
+ return NULL;
+}
+
+static void cancel_join_vcpu_thread(pthread_t thread, struct kvm_vcpu *vcpu)
+{
+ void *retval;
+ int r;
+
+ r = pthread_cancel(thread);
+ TEST_ASSERT(!r, "pthread_cancel on vcpu_id=%d failed with errno=%d",
+ vcpu->id, r);
+
+ r = pthread_join(thread, &retval);
+ TEST_ASSERT(!r, "pthread_join on vcpu_id=%d failed with errno=%d",
+ vcpu->id, r);
+ TEST_ASSERT(retval == PTHREAD_CANCELED,
+ "expected retval=%p, got %p", PTHREAD_CANCELED,
+ retval);
+}
+
+int main(int argc, char *argv[])
+{
+ struct kvm_vm *vm;
+ struct kvm_vcpu *vcpu[3];
+ unsigned int exit_reason;
+ pthread_t threads[2];
+ vm_vaddr_t test_data_page, gva;
+ vm_paddr_t gpa;
+ uint64_t *pte;
+ struct test_data *data;
+ struct ucall uc;
+ int stage = 1, r, i;
+
+ vm = vm_create_with_one_vcpu(&vcpu[0], sender_guest_code);
+
+ /* Test data page */
+ test_data_page = vm_vaddr_alloc_page(vm);
+ data = (struct test_data *)addr_gva2hva(vm, test_data_page);
+
+ /* Hypercall input/output */
+ data->hcall_gva = vm_vaddr_alloc_pages(vm, 2);
+ data->hcall_gpa = addr_gva2gpa(vm, data->hcall_gva);
+ memset(addr_gva2hva(vm, data->hcall_gva), 0x0, 2 * PAGE_SIZE);
+
+ /*
+ * Test pages: the first one is filled with '0x01's, the second with '0x02's
+ * and the test will swap their mappings. The third page keeps the indication
+ * about the current state of mappings.
+ */
+ data->test_pages = vm_vaddr_alloc_pages(vm, NTEST_PAGES + 1);
+ for (i = 0; i < NTEST_PAGES; i++)
+ memset(addr_gva2hva(vm, data->test_pages + PAGE_SIZE * i),
+ (u8)(i + 1), PAGE_SIZE);
+ set_expected_val(addr_gva2hva(vm, data->test_pages), 0x0, WORKER_VCPU_ID_1);
+ set_expected_val(addr_gva2hva(vm, data->test_pages), 0x0, WORKER_VCPU_ID_2);
+
+ /*
+ * Get PTE pointers for test pages and map them inside the guest.
+ * Use separate page for each PTE for simplicity.
+ */
+ gva = vm_vaddr_unused_gap(vm, NTEST_PAGES * PAGE_SIZE, KVM_UTIL_MIN_VADDR);
+ for (i = 0; i < NTEST_PAGES; i++) {
+ pte = vm_get_page_table_entry(vm, vcpu[0], data->test_pages + i * PAGE_SIZE);
+ gpa = addr_hva2gpa(vm, pte);
+ __virt_pg_map(vm, gva + PAGE_SIZE * i, gpa & PAGE_MASK, PG_LEVEL_4K);
+ data->test_pages_pte[i] = gva + (gpa & ~PAGE_MASK);
+ }
+
+ /*
+ * Sender vCPU which performs the test: swaps test pages, sets expectation
+ * for 'workers' and issues TLB flush hypercalls.
+ */
+ vcpu_args_set(vcpu[0], 1, test_data_page);
+ vcpu_set_hv_cpuid(vcpu[0]);
+
+ /* Create worker vCPUs which check the contents of the test pages */
+ vcpu[1] = vm_vcpu_add(vm, WORKER_VCPU_ID_1, worker_guest_code);
+ vcpu_args_set(vcpu[1], 1, test_data_page);
+ vcpu_set_msr(vcpu[1], HV_X64_MSR_VP_INDEX, WORKER_VCPU_ID_1);
+ vcpu_set_hv_cpuid(vcpu[1]);
+
+ vcpu[2] = vm_vcpu_add(vm, WORKER_VCPU_ID_2, worker_guest_code);
+ vcpu_args_set(vcpu[2], 1, test_data_page);
+ vcpu_set_msr(vcpu[2], HV_X64_MSR_VP_INDEX, WORKER_VCPU_ID_2);
+ vcpu_set_hv_cpuid(vcpu[2]);
+
+ r = pthread_create(&threads[0], NULL, vcpu_thread, vcpu[1]);
+ TEST_ASSERT(!r, "pthread_create() failed");
+
+ r = pthread_create(&threads[1], NULL, vcpu_thread, vcpu[2]);
+ TEST_ASSERT(!r, "pthread_create() failed");
+
+ while (true) {
+ vcpu_run(vcpu[0]);
+ exit_reason = vcpu[0]->run->exit_reason;
+
+ TEST_ASSERT(exit_reason == KVM_EXIT_IO,
+ "unexpected exit reason: %u (%s)",
+ exit_reason, exit_reason_str(exit_reason));
+
+ switch (get_ucall(vcpu[0], &uc)) {
+ case UCALL_SYNC:
+ TEST_ASSERT(uc.args[1] == stage,
+ "Unexpected stage: %ld (%d expected)\n",
+ uc.args[1], stage);
+ break;
+ case UCALL_ABORT:
+ REPORT_GUEST_ASSERT(uc);
+ /* NOT REACHED */
+ case UCALL_DONE:
+ goto done;
+ default:
+ TEST_FAIL("Unknown ucall %lu", uc.cmd);
+ }
+
+ stage++;
+ }
+
+done:
+ cancel_join_vcpu_thread(threads[0], vcpu[1]);
+ cancel_join_vcpu_thread(threads[1], vcpu[2]);
+ kvm_vm_free(vm);
+
+ return 0;
+}
--
2.37.3

2022-10-21 16:18:34

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 45/46] KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test

Enable Hyper-V L2 TLB flush and check that Hyper-V TLB flush hypercalls
from L2 don't exit to L1 unless 'TlbLockCount' is set in the Partition
assist page.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/svm.h | 4 ++
.../selftests/kvm/x86_64/hyperv_svm_test.c | 61 +++++++++++++++++--
2 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/svm.h b/tools/testing/selftests/kvm/include/x86_64/svm.h
index 483e6ae12f69..4803e1056055 100644
--- a/tools/testing/selftests/kvm/include/x86_64/svm.h
+++ b/tools/testing/selftests/kvm/include/x86_64/svm.h
@@ -76,6 +76,10 @@ struct hv_vmcb_enlightenments {
*/
#define HV_VMCB_NESTED_ENLIGHTENMENTS (1U << 31)

+/* Synthetic VM-Exit */
+#define HV_SVM_EXITCODE_ENL 0xf0000000
+#define HV_SVM_ENL_EXITCODE_TRAP_AFTER_FLUSH (1)
+
struct __attribute__ ((__packed__)) vmcb_control_area {
u32 intercept_cr;
u32 intercept_dr;
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
index 1c3fc38b4f15..edb779615a79 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
@@ -25,6 +25,8 @@

void l2_guest_code(void)
{
+ u64 unused;
+
GUEST_SYNC(3);
/* Exit to L1 */
vmmcall();
@@ -38,11 +40,30 @@ void l2_guest_code(void)

GUEST_SYNC(5);

+ /* L2 TLB flush tests */
+ hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE |
+ HV_HYPERCALL_FAST_BIT, 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
+ HV_FLUSH_ALL_PROCESSORS);
+ rdmsr(MSR_FS_BASE);
+ /*
+ * Note: hypercall status (RAX) is not preserved correctly by L1 after
+ * synthetic vmexit, use unchecked version.
+ */
+ __hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE |
+ HV_HYPERCALL_FAST_BIT, 0x0,
+ HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
+ HV_FLUSH_ALL_PROCESSORS, &unused);
+ /* Make sure we're not issuing Hyper-V TLB flush call again */
+ __asm__ __volatile__ ("mov $0xdeadbeef, %rcx");
+
/* Done, exit to L1 and never come back. */
vmmcall();
}

-static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)
+static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm,
+ struct hyperv_test_pages *hv_pages,
+ vm_vaddr_t pgs_gpa)
{
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
struct vmcb *vmcb = svm->vmcb;
@@ -50,13 +71,23 @@ static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)

GUEST_SYNC(1);

- wrmsr(HV_X64_MSR_GUEST_OS_ID, (u64)0x8100 << 48);
+ wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
+ wrmsr(HV_X64_MSR_HYPERCALL, pgs_gpa);
+ enable_vp_assist(hv_pages->vp_assist_gpa, hv_pages->vp_assist);

GUEST_ASSERT(svm->vmcb_gpa);
/* Prepare for L2 execution. */
generic_svm_setup(svm, l2_guest_code,
&l2_guest_stack[L2_GUEST_STACK_SIZE]);

+ /* L2 TLB flush setup */
+ hve->partition_assist_page = hv_pages->partition_assist_gpa;
+ hve->hv_enlightenments_control.nested_flush_hypercall = 1;
+ hve->hv_vm_id = 1;
+ hve->hv_vp_id = 1;
+ current_vp_assist->nested_control.features.directhypercall = 1;
+ *(u32 *)(hv_pages->partition_assist) = 0;
+
GUEST_SYNC(2);
run_guest(vmcb, svm->vmcb_gpa);
GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
@@ -91,6 +122,20 @@ static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)
GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_MSR);
vmcb->save.rip += 2; /* rdmsr */

+
+ /*
+ * L2 TLB flush test. First VMCALL should be handled directly by L0,
+ * no VMCALL exit expected.
+ */
+ run_guest(vmcb, svm->vmcb_gpa);
+ GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_MSR);
+ vmcb->save.rip += 2; /* rdmsr */
+ /* Enable synthetic vmexit */
+ *(u32 *)(hv_pages->partition_assist) = 1;
+ run_guest(vmcb, svm->vmcb_gpa);
+ GUEST_ASSERT(vmcb->control.exit_code == HV_SVM_EXITCODE_ENL);
+ GUEST_ASSERT(vmcb->control.exit_info_1 == HV_SVM_ENL_EXITCODE_TRAP_AFTER_FLUSH);
+
run_guest(vmcb, svm->vmcb_gpa);
GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
GUEST_SYNC(6);
@@ -100,8 +145,8 @@ static void __attribute__((__flatten__)) guest_code(struct svm_test_data *svm)

int main(int argc, char *argv[])
{
- vm_vaddr_t nested_gva = 0;
-
+ vm_vaddr_t nested_gva = 0, hv_pages_gva = 0;
+ vm_vaddr_t hcall_page;
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
struct kvm_run *run;
@@ -115,7 +160,13 @@ int main(int argc, char *argv[])
vcpu_set_hv_cpuid(vcpu);
run = vcpu->run;
vcpu_alloc_svm(vm, &nested_gva);
- vcpu_args_set(vcpu, 1, nested_gva);
+ vcpu_alloc_hyperv_test_pages(vm, &hv_pages_gva);
+
+ hcall_page = vm_vaddr_alloc_pages(vm, 1);
+ memset(addr_gva2hva(vm, hcall_page), 0x0, getpagesize());
+
+ vcpu_args_set(vcpu, 3, nested_gva, hv_pages_gva, addr_gva2gpa(vm, hcall_page));
+ vcpu_set_msr(vcpu, HV_X64_MSR_VP_INDEX, vcpu->id);

for (stage = 1;; stage++) {
vcpu_run(vcpu);
--
2.37.3

2022-10-21 16:18:52

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 22/46] KVM: x86: hyper-v: Introduce kvm_hv_is_tlb_flush_hcall()

The newly introduced helper checks whether vCPU is performing a
Hyper-V TLB flush hypercall. This is required to filter out L2 TLB
flush hypercalls for processing.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.h | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 8942e8c6c912..5f9c76b45f46 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -177,6 +177,23 @@ static inline void kvm_hv_vcpu_purge_flush_tlb(struct kvm_vcpu *vcpu)
kfifo_reset_out(&tlb_flush_fifo->entries);
}

+static inline bool kvm_hv_is_tlb_flush_hcall(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ u16 code;
+
+ if (!hv_vcpu)
+ return false;
+
+ code = is_64_bit_hypercall(vcpu) ? kvm_rcx_read(vcpu) :
+ kvm_rax_read(vcpu);
+
+ return (code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE ||
+ code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
+ code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX ||
+ code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX);
+}
+
int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu);

#endif
--
2.37.3

2022-10-21 16:20:25

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 46/46] KVM: selftests: Rename 'evmcs_test' to 'hyperv_evmcs'

Conform to the rest of Hyper-V emulation selftests which have 'hyperv'
prefix. Get rid of '_test' suffix as well as the purpose of this code
is fairly obvious.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/.gitignore | 2 +-
tools/testing/selftests/kvm/Makefile | 2 +-
.../selftests/kvm/x86_64/{evmcs_test.c => hyperv_evmcs.c} | 0
3 files changed, 2 insertions(+), 2 deletions(-)
rename tools/testing/selftests/kvm/x86_64/{evmcs_test.c => hyperv_evmcs.c} (100%)

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 68d3d2080b59..edca2d3823d1 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -16,7 +16,6 @@
/x86_64/cpuid_test
/x86_64/cr4_cpuid_sync_test
/x86_64/debug_regs
-/x86_64/evmcs_test
/x86_64/emulator_error_test
/x86_64/fix_hypercall_test
/x86_64/get_msr_index_features
@@ -24,6 +23,7 @@
/x86_64/kvm_pv_test
/x86_64/hyperv_clock
/x86_64/hyperv_cpuid
+/x86_64/hyperv_evmcs
/x86_64/hyperv_features
/x86_64/hyperv_ipi
/x86_64/hyperv_svm_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index eee6421cf4a8..379a83ba4912 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -81,11 +81,11 @@ TEST_PROGS_x86_64 += x86_64/nx_huge_pages_test.sh
TEST_GEN_PROGS_x86_64 = x86_64/cpuid_test
TEST_GEN_PROGS_x86_64 += x86_64/cr4_cpuid_sync_test
TEST_GEN_PROGS_x86_64 += x86_64/get_msr_index_features
-TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test
TEST_GEN_PROGS_x86_64 += x86_64/emulator_error_test
TEST_GEN_PROGS_x86_64 += x86_64/fix_hypercall_test
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid
+TEST_GEN_PROGS_x86_64 += x86_64/hyperv_evmcs
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_features
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_ipi
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_svm_test
diff --git a/tools/testing/selftests/kvm/x86_64/evmcs_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c
similarity index 100%
rename from tools/testing/selftests/kvm/x86_64/evmcs_test.c
rename to tools/testing/selftests/kvm/x86_64/hyperv_evmcs.c
--
2.37.3

2022-10-21 16:21:17

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 26/46] KVM: nVMX: hyper-v: Enable L2 TLB flush

Enable L2 TLB flush feature on nVMX when:
- Enlightened VMCS is in use.
- The feature flag is enabled in eVMCS.
- The feature flag is enabled in partition assist page.

Perform synthetic vmexit to L1 after processing TLB flush call upon
request (HV_VMX_SYNTHETIC_EXIT_REASON_TRAP_AFTER_FLUSH).

Note: nested_evmcs_l2_tlb_flush_enabled() uses cached VP assist page copy
which gets updated from nested_vmx_handle_enlightened_vmptrld(). This is
also guaranteed to happen post migration with eVMCS backed L2 running.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/hyperv-tlfs.h | 9 +++++++++
arch/x86/kvm/vmx/hyperv.c | 17 +++++++++++++++++
arch/x86/kvm/vmx/hyperv.h | 1 +
arch/x86/kvm/vmx/nested.c | 20 ++++++++++++++++++++
4 files changed, 47 insertions(+)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 6639979302ab..b25c6792d409 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -600,6 +600,15 @@ struct hv_enlightened_vmcs {

#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL 0xFFFF

+/*
+ * Note, Hyper-V isn't actually stealing bit 28 from Intel, just abusing it by
+ * pairing it with architecturally impossible exit reasons. Bit 28 is set only
+ * on SMI exits to a SMI transfer monitor (STM) and if and only if a MTF VM-Exit
+ * is pending. I.e. it will never be set by hardware for non-SMI exits (there
+ * are only three), nor will it ever be set unless the VMM is an STM.
+ */
+#define HV_VMX_SYNTHETIC_EXIT_REASON_TRAP_AFTER_FLUSH 0x10000031
+
/*
* Hyper-V uses the software reserved 32 bytes in VMCB control area to expose
* SVM enlightenments to guests.
diff --git a/arch/x86/kvm/vmx/hyperv.c b/arch/x86/kvm/vmx/hyperv.c
index bceca1a99804..04a0bba58c7d 100644
--- a/arch/x86/kvm/vmx/hyperv.c
+++ b/arch/x86/kvm/vmx/hyperv.c
@@ -5,6 +5,7 @@

#include "../cpuid.h"
#include "hyperv.h"
+#include "nested.h"
#include "vmcs.h"
#include "vmx.h"
#include "trace.h"
@@ -500,6 +501,22 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu,
return 0;
}

+bool nested_evmcs_l2_tlb_flush_enabled(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
+ struct hv_enlightened_vmcs *evmcs = vmx->nested.hv_evmcs;
+
+ if (!hv_vcpu || !evmcs)
+ return false;
+
+ if (!evmcs->hv_enlightenments_control.nested_flush_hypercall)
+ return false;
+
+ return hv_vcpu->vp_assist_page.nested_control.features.directhypercall;
+}
+
void vmx_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu)
{
+ nested_vmx_vmexit(vcpu, HV_VMX_SYNTHETIC_EXIT_REASON_TRAP_AFTER_FLUSH, 0, 0);
}
diff --git a/arch/x86/kvm/vmx/hyperv.h b/arch/x86/kvm/vmx/hyperv.h
index 8bf366730d33..571e7929d14e 100644
--- a/arch/x86/kvm/vmx/hyperv.h
+++ b/arch/x86/kvm/vmx/hyperv.h
@@ -243,6 +243,7 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu,
uint16_t *vmcs_version);
void nested_evmcs_filter_control_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata);
int nested_evmcs_check_controls(struct vmcs12 *vmcs12);
+bool nested_evmcs_l2_tlb_flush_enabled(struct kvm_vcpu *vcpu);
void vmx_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu);

#endif /* __KVM_X86_VMX_HYPERV_H */
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 29a210df4066..d9814b91877c 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -1131,6 +1131,15 @@ static void nested_vmx_transition_tlb_flush(struct kvm_vcpu *vcpu,
{
struct vcpu_vmx *vmx = to_vmx(vcpu);

+ /*
+ * KVM_REQ_HV_TLB_FLUSH flushes entries from either L1's VP_ID or
+ * L2's VP_ID upon request from the guest. Make sure we check for
+ * pending entries in the right FIFO upon L1/L2 transition as these
+ * requests are put by other vCPUs asynchronously.
+ */
+ if (to_hv_vcpu(vcpu) && enable_ept)
+ kvm_make_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+
/*
* If vmcs12 doesn't use VPID, L1 expects linear and combined mappings
* for *all* contexts to be flushed on VM-Enter/VM-Exit, i.e. it's a
@@ -3266,6 +3275,12 @@ static bool nested_get_vmcs12_pages(struct kvm_vcpu *vcpu)

static bool vmx_get_nested_state_pages(struct kvm_vcpu *vcpu)
{
+ /*
+ * Note: nested_get_evmcs_page() also updates 'vp_assist_page' copy
+ * in 'struct kvm_vcpu_hv' in case eVMCS is in use, this is mandatory
+ * to make nested_evmcs_l2_tlb_flush_enabled() work correctly post
+ * migration.
+ */
if (!nested_get_evmcs_page(vcpu)) {
pr_debug_ratelimited("%s: enlightened vmptrld failed\n",
__func__);
@@ -6142,6 +6157,11 @@ static bool nested_vmx_l0_wants_exit(struct kvm_vcpu *vcpu,
* Handle L2's bus locks in L0 directly.
*/
return true;
+ case EXIT_REASON_VMCALL:
+ /* Hyper-V L2 TLB flush hypercall is handled by L0 */
+ return guest_hv_cpuid_has_l2_tlb_flush(vcpu) &&
+ nested_evmcs_l2_tlb_flush_enabled(vcpu) &&
+ kvm_hv_is_tlb_flush_hcall(vcpu);
default:
break;
}
--
2.37.3

2022-10-21 16:21:19

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 28/46] KVM: nSVM: hyper-v: Enable L2 TLB flush

Implement Hyper-V L2 TLB flush for nSVM. The feature needs to be enabled
both in extended 'nested controls' in VMCB and VP assist page.
According to Hyper-V TLFS, synthetic vmexit to L1 is performed with
- HV_SVM_EXITCODE_ENL exit_code.
- HV_SVM_ENL_EXITCODE_TRAP_AFTER_FLUSH exit_info_1.

Note: VP assist page is cached in 'struct kvm_vcpu_hv' so
recalc_intercepts() doesn't need to read from guest's memory. KVM
needs to update the case upon each VMRUN and after svm_set_nested_state
(svm_get_nested_state_pages()) to handle the case when the guest got
migrated while L2 was running.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/hyperv-tlfs.h | 4 ++++
arch/x86/kvm/hyperv.h | 11 ++++++++++
arch/x86/kvm/svm/hyperv.c | 7 ++++++
arch/x86/kvm/svm/hyperv.h | 15 +++++++++++++
arch/x86/kvm/svm/nested.c | 35 ++++++++++++++++++++++++++++--
5 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index b25c6792d409..e3efaf6e6b62 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -631,6 +631,10 @@ struct hv_vmcb_enlightenments {
*/
#define HV_VMCB_NESTED_ENLIGHTENMENTS 31

+/* Synthetic VM-Exit */
+#define HV_SVM_EXITCODE_ENL 0xf0000000
+#define HV_SVM_ENL_EXITCODE_TRAP_AFTER_FLUSH (1)
+
struct hv_partition_assist_pg {
u32 tlb_lock_count;
};
diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 5157622c2fb3..9f96414a31c5 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -198,6 +198,17 @@ static inline bool kvm_hv_is_tlb_flush_hcall(struct kvm_vcpu *vcpu)
code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX);
}

+static inline int kvm_hv_verify_vp_assist(struct kvm_vcpu *vcpu)
+{
+ if (!to_hv_vcpu(vcpu))
+ return 0;
+
+ if (!kvm_hv_assist_page_enabled(vcpu))
+ return 0;
+
+ return kvm_hv_get_assist_page(vcpu);
+}
+
int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu);

#endif
diff --git a/arch/x86/kvm/svm/hyperv.c b/arch/x86/kvm/svm/hyperv.c
index 911f51021af1..088f6429b24c 100644
--- a/arch/x86/kvm/svm/hyperv.c
+++ b/arch/x86/kvm/svm/hyperv.c
@@ -8,4 +8,11 @@

void svm_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu)
{
+ struct vcpu_svm *svm = to_svm(vcpu);
+
+ svm->vmcb->control.exit_code = HV_SVM_EXITCODE_ENL;
+ svm->vmcb->control.exit_code_hi = 0;
+ svm->vmcb->control.exit_info_1 = HV_SVM_ENL_EXITCODE_TRAP_AFTER_FLUSH;
+ svm->vmcb->control.exit_info_2 = 0;
+ nested_svm_vmexit(svm);
}
diff --git a/arch/x86/kvm/svm/hyperv.h b/arch/x86/kvm/svm/hyperv.h
index 7564bdf652e4..02f4784b5d44 100644
--- a/arch/x86/kvm/svm/hyperv.h
+++ b/arch/x86/kvm/svm/hyperv.h
@@ -25,6 +25,21 @@ static inline void nested_svm_hv_update_vm_vp_ids(struct kvm_vcpu *vcpu)
hv_vcpu->nested.vp_id = hve->hv_vp_id;
}

+static inline bool nested_svm_l2_tlb_flush_enabled(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_svm *svm = to_svm(vcpu);
+ struct hv_vmcb_enlightenments *hve = &svm->nested.ctl.hv_enlightenments;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+
+ if (!hv_vcpu)
+ return false;
+
+ if (!hve->hv_enlightenments_control.nested_flush_hypercall)
+ return false;
+
+ return hv_vcpu->vp_assist_page.nested_control.features.directhypercall;
+}
+
void svm_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu);

#endif /* __ARCH_X86_KVM_SVM_HYPERV_H__ */
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 05889d5a8629..8f67b8fb3c1f 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -149,8 +149,12 @@ void recalc_intercepts(struct vcpu_svm *svm)
vmcb_clr_intercept(c, INTERCEPT_VINTR);
}

- /* We don't want to see VMMCALLs from a nested guest */
- vmcb_clr_intercept(c, INTERCEPT_VMMCALL);
+ /*
+ * We want to see VMMCALLs from a nested guest only when Hyper-V L2 TLB
+ * flush feature is enabled.
+ */
+ if (!nested_svm_l2_tlb_flush_enabled(&svm->vcpu))
+ vmcb_clr_intercept(c, INTERCEPT_VMMCALL);

for (i = 0; i < MAX_INTERCEPT; i++)
c->intercepts[i] |= g->intercepts[i];
@@ -472,6 +476,15 @@ static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm,

static void nested_svm_transition_tlb_flush(struct kvm_vcpu *vcpu)
{
+ /*
+ * KVM_REQ_HV_TLB_FLUSH flushes entries from either L1's VP_ID or
+ * L2's VP_ID upon request from the guest. Make sure we check for
+ * pending entries in the right FIFO upon L1/L2 transition as these
+ * requests are put by other vCPUs asynchronously.
+ */
+ if (to_hv_vcpu(vcpu) && npt_enabled)
+ kvm_make_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+
/*
* TODO: optimize unconditional TLB flush/MMU sync. A partial list of
* things to fix before this can be conditional:
@@ -823,6 +836,13 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu)
return 1;
}

+ /* This fails when VP assist page is enabled but the supplied GPA is bogus */
+ ret = kvm_hv_verify_vp_assist(vcpu);
+ if (ret) {
+ kvm_inject_gp(vcpu, 0);
+ return ret;
+ }
+
vmcb12_gpa = svm->vmcb->save.rax;
ret = kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map);
if (ret == -EINVAL) {
@@ -1412,6 +1432,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
int nested_svm_exit_special(struct vcpu_svm *svm)
{
u32 exit_code = svm->vmcb->control.exit_code;
+ struct kvm_vcpu *vcpu = &svm->vcpu;

switch (exit_code) {
case SVM_EXIT_INTR:
@@ -1430,6 +1451,13 @@ int nested_svm_exit_special(struct vcpu_svm *svm)
return NESTED_EXIT_HOST;
break;
}
+ case SVM_EXIT_VMMCALL:
+ /* Hyper-V L2 TLB flush hypercall is handled by L0 */
+ if (guest_hv_cpuid_has_l2_tlb_flush(vcpu) &&
+ nested_svm_l2_tlb_flush_enabled(vcpu) &&
+ kvm_hv_is_tlb_flush_hcall(vcpu))
+ return NESTED_EXIT_HOST;
+ break;
default:
break;
}
@@ -1710,6 +1738,9 @@ static bool svm_get_nested_state_pages(struct kvm_vcpu *vcpu)
return false;
}

+ if (kvm_hv_verify_vp_assist(vcpu))
+ return false;
+
return true;
}

--
2.37.3

2022-10-21 16:21:50

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 09/46] KVM: x86: hyper-v: Introduce TLB flush fifo

To allow flushing individual GVAs instead of always flushing the whole
VPID a per-vCPU structure to pass the requests is needed. Use standard
'kfifo' to queue two types of entries: individual GVA (GFN + up to 4095
following GFNs in the lower 12 bits) and 'flush all'.

The size of the fifo is arbitrarily set to '16'.

Note, kvm_hv_flush_tlb() only queues 'flush all' entries for now and
kvm_hv_vcpu_flush_tlb() doesn't actually read the fifo just resets the
queue before returning -EOPNOTSUPP (which triggers full TLB flush) so
the functional change is very small but the infrastructure is prepared
to handle individual GVA flush requests.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 20 ++++++++++++++
arch/x86/kvm/hyperv.c | 47 +++++++++++++++++++++++++++++++++
arch/x86/kvm/hyperv.h | 15 +++++++++++
arch/x86/kvm/svm/svm.c | 2 +-
arch/x86/kvm/x86.c | 11 ++++++--
5 files changed, 92 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 05d90e11e535..f8ee72dd8660 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -25,6 +25,7 @@
#include <linux/clocksource.h>
#include <linux/irqbypass.h>
#include <linux/hyperv.h>
+#include <linux/kfifo.h>

#include <asm/apic.h>
#include <asm/pvclock-abi.h>
@@ -599,6 +600,23 @@ struct kvm_vcpu_hv_synic {
bool dont_zero_synic_pages;
};

+/* The maximum number of entries on the TLB flush fifo. */
+#define KVM_HV_TLB_FLUSH_FIFO_SIZE (16)
+/*
+ * Note: the following 'magic' entry is made up by KVM to avoid putting
+ * anything besides GVA on the TLB flush fifo. It is theoretically possible
+ * to observe a request to flush 4095 PFNs starting from 0xfffffffffffff000
+ * which will look identical. KVM's action to 'flush everything' instead of
+ * flushing these particular addresses is, however, fully legitimate as
+ * flushing more than requested is always OK.
+ */
+#define KVM_HV_TLB_FLUSHALL_ENTRY ((u64)-1)
+
+struct kvm_vcpu_hv_tlb_flush_fifo {
+ spinlock_t write_lock;
+ DECLARE_KFIFO(entries, u64, KVM_HV_TLB_FLUSH_FIFO_SIZE);
+};
+
/* Hyper-V per vcpu emulation context */
struct kvm_vcpu_hv {
struct kvm_vcpu *vcpu;
@@ -620,6 +638,8 @@ struct kvm_vcpu_hv {
u32 nested_eax; /* HYPERV_CPUID_NESTED_FEATURES.EAX */
u32 nested_ebx; /* HYPERV_CPUID_NESTED_FEATURES.EBX */
} cpuid_cache;
+
+ struct kvm_vcpu_hv_tlb_flush_fifo tlb_flush_fifo;
};

/* Xen HVM per vcpu emulation context */
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 3c0f639f6a05..9d9a5ff2d54b 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -29,6 +29,7 @@
#include <linux/kvm_host.h>
#include <linux/highmem.h>
#include <linux/sched/cputime.h>
+#include <linux/spinlock.h>
#include <linux/eventfd.h>

#include <asm/apicdef.h>
@@ -954,6 +955,9 @@ int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)

hv_vcpu->vp_index = vcpu->vcpu_idx;

+ INIT_KFIFO(hv_vcpu->tlb_flush_fifo.entries);
+ spin_lock_init(&hv_vcpu->tlb_flush_fifo.write_lock);
+
return 0;
}

@@ -1783,6 +1787,37 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc,
var_cnt * sizeof(*sparse_banks));
}

+static void hv_tlb_flush_enqueue(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ u64 flush_all_entry = KVM_HV_TLB_FLUSHALL_ENTRY;
+
+ if (!hv_vcpu)
+ return;
+
+ tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;
+
+ kfifo_in_spinlocked_noirqsave(&tlb_flush_fifo->entries, &flush_all_entry,
+ 1, &tlb_flush_fifo->write_lock);
+}
+
+int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+
+ if (!hv_vcpu)
+ return -EINVAL;
+
+ tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;
+
+ kfifo_reset_out(&tlb_flush_fifo->entries);
+
+ /* Precise flushing isn't implemented yet. */
+ return -EOPNOTSUPP;
+}
+
static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
{
struct kvm *kvm = vcpu->kvm;
@@ -1791,6 +1826,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS);
u64 valid_bank_mask;
u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS];
+ struct kvm_vcpu *v;
+ unsigned long i;
bool all_cpus;

/*
@@ -1870,10 +1907,20 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
* analyze it here, flush TLB regardless of the specified address space.
*/
if (all_cpus) {
+ kvm_for_each_vcpu(i, v, kvm)
+ hv_tlb_flush_enqueue(v);
+
kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
} else {
sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);

+ for_each_set_bit(i, vcpu_mask, KVM_MAX_VCPUS) {
+ v = kvm_get_vcpu(kvm, i);
+ if (!v)
+ continue;
+ hv_tlb_flush_enqueue(v);
+ }
+
kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
}

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 1030b1b50552..f79edf9234cd 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -151,4 +151,19 @@ int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args);
int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
struct kvm_cpuid_entry2 __user *entries);

+static inline void kvm_hv_vcpu_purge_flush_tlb(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv_tlb_flush_fifo *tlb_flush_fifo;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+
+ if (!hv_vcpu || !kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu))
+ return;
+
+ tlb_flush_fifo = &hv_vcpu->tlb_flush_fifo;
+
+ kfifo_reset_out(&tlb_flush_fifo->entries);
+}
+
+int kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu);
+
#endif
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 9210a8840224..25dc38a94fa0 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3743,7 +3743,7 @@ static void svm_flush_tlb_current(struct kvm_vcpu *vcpu)
* A TLB flush for the current ASID flushes both "host" and "guest" TLB
* entries, and thus is a superset of Hyper-V's fine grained flushing.
*/
- kvm_clear_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+ kvm_hv_vcpu_purge_flush_tlb(vcpu);

/*
* Flush only the current ASID even if the TLB flush was invoked via
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bf2aa77b7a2f..ed8b7802ba88 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3422,7 +3422,7 @@ static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu)
* Flushing all "guest" TLB is always a superset of Hyper-V's fine
* grained flushing.
*/
- kvm_clear_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+ kvm_hv_vcpu_purge_flush_tlb(vcpu);
}


@@ -10497,7 +10497,14 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)

kvm_service_local_tlb_flush_requests(vcpu);

- if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu))
+ /*
+ * Fall back to a "full" guest flush if Hyper-V's precise
+ * flushing fails. Note, Hyper-V's flushing is per-vCPU, but
+ * the flushes are considered "remote" and not "local" because
+ * the requests can be initiated from other vCPUs.
+ */
+ if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu) &&
+ kvm_hv_vcpu_flush_tlb(vcpu))
kvm_vcpu_flush_tlb_guest(vcpu);

if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) {
--
2.37.3

2022-10-21 16:21:57

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 32/46] KVM: selftests: Move the function doing Hyper-V hypercall to a common header

All Hyper-V specific tests issuing hypercalls need this.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/hyperv.h | 18 ++++++++++++++++++
.../selftests/kvm/x86_64/hyperv_features.c | 19 +------------------
2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index f0a8a93694b2..40f8b1b423fc 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -185,6 +185,24 @@
/* hypercall options */
#define HV_HYPERCALL_FAST_BIT BIT(16)

+static inline uint8_t hyperv_hypercall(u64 control, vm_vaddr_t input_address,
+ vm_vaddr_t output_address,
+ uint64_t *hv_status)
+{
+ uint8_t vector;
+
+ /* Note both the hypercall and the "asm safe" clobber r9-r11. */
+ asm volatile("mov %[output_address], %%r8\n\t"
+ KVM_ASM_SAFE("vmcall")
+ : "=a" (*hv_status),
+ "+c" (control), "+d" (input_address),
+ KVM_ASM_SAFE_OUTPUTS(vector)
+ : [output_address] "r"(output_address),
+ "a" (-EFAULT)
+ : "cc", "memory", "r8", KVM_ASM_SAFE_CLOBBERS);
+ return vector;
+}
+
/* Proper HV_X64_MSR_GUEST_OS_ID value */
#define HYPERV_LINUX_OS_ID ((u64)0x8100 << 48)

diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_features.c b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
index 71bb91602a7f..5ff4ff2365bb 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_features.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_features.c
@@ -13,23 +13,6 @@
#include "processor.h"
#include "hyperv.h"

-static inline uint8_t hypercall(u64 control, vm_vaddr_t input_address,
- vm_vaddr_t output_address, uint64_t *hv_status)
-{
- uint8_t vector;
-
- /* Note both the hypercall and the "asm safe" clobber r9-r11. */
- asm volatile("mov %[output_address], %%r8\n\t"
- KVM_ASM_SAFE("vmcall")
- : "=a" (*hv_status),
- "+c" (control), "+d" (input_address),
- KVM_ASM_SAFE_OUTPUTS(vector)
- : [output_address] "r"(output_address),
- "a" (-EFAULT)
- : "cc", "memory", "r8", KVM_ASM_SAFE_CLOBBERS);
- return vector;
-}
-
struct msr_data {
uint32_t idx;
bool available;
@@ -79,7 +62,7 @@ static void guest_hcall(vm_vaddr_t pgs_gpa, struct hcall_data *hcall)
input = output = 0;
}

- vector = hypercall(hcall->control, input, output, &res);
+ vector = hyperv_hypercall(hcall->control, input, output, &res);
if (hcall->ud_expected) {
GUEST_ASSERT_2(vector == UD_VECTOR, hcall->control, vector);
} else {
--
2.37.3

2022-10-21 16:24:04

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 39/46] KVM: selftests: Sync 'struct hv_vp_assist_page' definition with hyperv-tlfs.h

'struct hv_vp_assist_page' definition doesn't match TLFS. Also, define
'struct hv_nested_enlightenments_control' and use it instead of opaque
'__u64'.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
.../selftests/kvm/include/x86_64/evmcs.h | 22 ++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/evmcs.h b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
index 4b6840df2979..efdc62704f27 100644
--- a/tools/testing/selftests/kvm/include/x86_64/evmcs.h
+++ b/tools/testing/selftests/kvm/include/x86_64/evmcs.h
@@ -20,14 +20,26 @@

extern bool enable_evmcs;

+struct hv_nested_enlightenments_control {
+ struct {
+ __u32 directhypercall:1;
+ __u32 reserved:31;
+ } features;
+ struct {
+ __u32 reserved;
+ } hypercallControls;
+} __packed;
+
+/* Define virtual processor assist page structure. */
struct hv_vp_assist_page {
__u32 apic_assist;
- __u32 reserved;
- __u64 vtl_control[2];
- __u64 nested_enlightenments_control[2];
- __u32 enlighten_vmentry;
+ __u32 reserved1;
+ __u64 vtl_control[3];
+ struct hv_nested_enlightenments_control nested_control;
+ __u8 enlighten_vmentry;
+ __u8 reserved2[7];
__u64 current_nested_vmcs;
-};
+} __packed;

struct hv_enlightened_vmcs {
u32 revision_id;
--
2.37.3

2022-10-21 16:25:05

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 43/46] KVM: selftests: Allocate Hyper-V partition assist page

In preparation to testing Hyper-V L2 TLB flush hypercalls, allocate
so-called Partition assist page.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
tools/testing/selftests/kvm/include/x86_64/hyperv.h | 5 +++++
tools/testing/selftests/kvm/lib/x86_64/hyperv.c | 5 +++++
2 files changed, 10 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/x86_64/hyperv.h b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
index 186f3aab888f..ffe28a78c8a3 100644
--- a/tools/testing/selftests/kvm/include/x86_64/hyperv.h
+++ b/tools/testing/selftests/kvm/include/x86_64/hyperv.h
@@ -273,6 +273,11 @@ struct hyperv_test_pages {
uint64_t vp_assist_gpa;
void *vp_assist;

+ /* Partition assist page */
+ void *partition_assist_hva;
+ uint64_t partition_assist_gpa;
+ void *partition_assist;
+
/* Enlightened VMCS */
void *enlightened_vmcs_hva;
uint64_t enlightened_vmcs_gpa;
diff --git a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
index a2fc083c65ef..efb7e7a1354d 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/hyperv.c
@@ -19,6 +19,11 @@ struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
hv->vp_assist_hva = addr_gva2hva(vm, (uintptr_t)hv->vp_assist);
hv->vp_assist_gpa = addr_gva2gpa(vm, (uintptr_t)hv->vp_assist);

+ /* Setup of a region of guest memory for the partition assist page. */
+ hv->partition_assist = (void *)vm_vaddr_alloc_page(vm);
+ hv->partition_assist_hva = addr_gva2hva(vm, (uintptr_t)hv->partition_assist);
+ hv->partition_assist_gpa = addr_gva2gpa(vm, (uintptr_t)hv->partition_assist);
+
/* Setup of a region of guest memory for the enlightened VMCS. */
hv->enlightened_vmcs = (void *)vm_vaddr_alloc_page(vm);
hv->enlightened_vmcs_hva = addr_gva2hva(vm, (uintptr_t)hv->enlightened_vmcs);
--
2.37.3

2022-10-21 16:25:35

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 25/46] KVM: nVMX: hyper-v: Cache VP assist page in 'struct kvm_vcpu_hv'

In preparation to enabling L2 TLB flush, cache VP assist page in
'struct kvm_vcpu_hv'. While on it, rename nested_enlightened_vmentry()
to nested_get_evmptr() and make it return eVMCS GPA directly.

No functional change intended.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/hyperv.c | 10 ++++++----
arch/x86/kvm/hyperv.h | 3 +--
arch/x86/kvm/vmx/hyperv.c | 21 +++++++--------------
arch/x86/kvm/vmx/hyperv.h | 2 +-
arch/x86/kvm/vmx/nested.c | 6 +++---
6 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index cccaf423f4d9..63fd3c160331 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -650,6 +650,8 @@ struct kvm_vcpu_hv {
/* Preallocated buffer for handling hypercalls passing sparse vCPU set */
u64 sparse_banks[HV_MAX_SPARSE_VCPU_BANKS];

+ struct hv_vp_assist_page vp_assist_page;
+
struct {
u64 pa_page_gpa;
u64 vm_id;
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index ec3051699d2a..90f37e58a9ed 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -900,13 +900,15 @@ bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);

-bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
- struct hv_vp_assist_page *assist_page)
+bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu)
{
- if (!kvm_hv_assist_page_enabled(vcpu))
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+
+ if (!hv_vcpu || !kvm_hv_assist_page_enabled(vcpu))
return false;
+
return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
- assist_page, sizeof(*assist_page));
+ &hv_vcpu->vp_assist_page, sizeof(struct hv_vp_assist_page));
}
EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index bd698eb2bda1..81313e418b80 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -108,8 +108,7 @@ int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages);
void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu);

bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu);
-bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu,
- struct hv_vp_assist_page *assist_page);
+bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu);

static inline struct kvm_vcpu_hv_stimer *to_hv_stimer(struct kvm_vcpu *vcpu,
int timer_index)
diff --git a/arch/x86/kvm/vmx/hyperv.c b/arch/x86/kvm/vmx/hyperv.c
index f05464db4fdc..bceca1a99804 100644
--- a/arch/x86/kvm/vmx/hyperv.c
+++ b/arch/x86/kvm/vmx/hyperv.c
@@ -321,24 +321,17 @@ const struct evmcs_field vmcs_field_to_evmcs_1[] = {
};
const unsigned int nr_evmcs_1_fields = ARRAY_SIZE(vmcs_field_to_evmcs_1);

-bool nested_enlightened_vmentry(struct kvm_vcpu *vcpu, u64 *evmcs_gpa)
+u64 nested_get_evmptr(struct kvm_vcpu *vcpu)
{
- struct hv_vp_assist_page assist_page;
-
- *evmcs_gpa = -1ull;
-
- if (unlikely(!kvm_hv_get_assist_page(vcpu, &assist_page)))
- return false;
-
- if (unlikely(!assist_page.enlighten_vmentry))
- return false;
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);

- if (unlikely(!evmptr_is_valid(assist_page.current_nested_vmcs)))
- return false;
+ if (unlikely(!kvm_hv_get_assist_page(vcpu)))
+ return EVMPTR_INVALID;

- *evmcs_gpa = assist_page.current_nested_vmcs;
+ if (unlikely(!hv_vcpu->vp_assist_page.enlighten_vmentry))
+ return EVMPTR_INVALID;

- return true;
+ return hv_vcpu->vp_assist_page.current_nested_vmcs;
}

uint16_t nested_get_evmcs_version(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx/hyperv.h b/arch/x86/kvm/vmx/hyperv.h
index 8efaffe9215b..8bf366730d33 100644
--- a/arch/x86/kvm/vmx/hyperv.h
+++ b/arch/x86/kvm/vmx/hyperv.h
@@ -237,7 +237,7 @@ enum nested_evmptrld_status {
EVMPTRLD_ERROR,
};

-bool nested_enlightened_vmentry(struct kvm_vcpu *vcpu, u64 *evmcs_gpa);
+u64 nested_get_evmptr(struct kvm_vcpu *vcpu);
uint16_t nested_get_evmcs_version(struct kvm_vcpu *vcpu);
int nested_enable_evmcs(struct kvm_vcpu *vcpu,
uint16_t *vmcs_version);
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index a89b8e6f90f3..29a210df4066 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -1991,7 +1991,8 @@ static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld(
if (likely(!guest_cpuid_has_evmcs(vcpu)))
return EVMPTRLD_DISABLED;

- if (!nested_enlightened_vmentry(vcpu, &evmcs_gpa)) {
+ evmcs_gpa = nested_get_evmptr(vcpu);
+ if (!evmptr_is_valid(evmcs_gpa)) {
nested_release_evmcs(vcpu);
return EVMPTRLD_DISABLED;
}
@@ -5219,7 +5220,6 @@ static int handle_vmclear(struct kvm_vcpu *vcpu)
struct vcpu_vmx *vmx = to_vmx(vcpu);
u32 zero = 0;
gpa_t vmptr;
- u64 evmcs_gpa;
int r;

if (!nested_vmx_check_permission(vcpu))
@@ -5245,7 +5245,7 @@ static int handle_vmclear(struct kvm_vcpu *vcpu)
* vmx->nested.hv_evmcs but this shouldn't be a problem.
*/
if (likely(!guest_cpuid_has_evmcs(vcpu) ||
- !nested_enlightened_vmentry(vcpu, &evmcs_gpa))) {
+ !evmptr_is_valid(nested_get_evmptr(vcpu)))) {
if (vmptr == vmx->nested.current_vmptr)
nested_release_vmcs12(vcpu);

--
2.37.3

2022-10-21 16:26:04

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 21/46] KVM: x86: Introduce .hv_inject_synthetic_vmexit_post_tlb_flush() nested hook

Hyper-V supports injecting synthetic L2->L1 exit after performing
L2 TLB flush operation but the procedure is vendor specific. Introduce
.hv_inject_synthetic_vmexit_post_tlb_flush nested hook for it.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/Makefile | 3 ++-
arch/x86/kvm/svm/hyperv.c | 11 +++++++++++
arch/x86/kvm/svm/hyperv.h | 2 ++
arch/x86/kvm/svm/nested.c | 1 +
arch/x86/kvm/vmx/hyperv.c | 4 ++++
arch/x86/kvm/vmx/hyperv.h | 1 +
arch/x86/kvm/vmx/nested.c | 1 +
8 files changed, 23 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/kvm/svm/hyperv.c

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ede163b6f955..cccaf423f4d9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1695,6 +1695,7 @@ struct kvm_x86_nested_ops {
int (*enable_evmcs)(struct kvm_vcpu *vcpu,
uint16_t *vmcs_version);
uint16_t (*get_evmcs_version)(struct kvm_vcpu *vcpu);
+ void (*hv_inject_synthetic_vmexit_post_tlb_flush)(struct kvm_vcpu *vcpu);
};

struct kvm_x86_init_ops {
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 4412f0b8244c..7ac6ea23122f 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -25,7 +25,8 @@ 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
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 svm/sev.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

ifdef CONFIG_HYPERV
kvm-amd-y += svm/svm_onhyperv.o
diff --git a/arch/x86/kvm/svm/hyperv.c b/arch/x86/kvm/svm/hyperv.c
new file mode 100644
index 000000000000..911f51021af1
--- /dev/null
+++ b/arch/x86/kvm/svm/hyperv.c
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD SVM specific code for Hyper-V on KVM.
+ *
+ * Copyright 2022 Red Hat, Inc. and/or its affiliates.
+ */
+#include "hyperv.h"
+
+void svm_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu)
+{
+}
diff --git a/arch/x86/kvm/svm/hyperv.h b/arch/x86/kvm/svm/hyperv.h
index e97d80974e72..7564bdf652e4 100644
--- a/arch/x86/kvm/svm/hyperv.h
+++ b/arch/x86/kvm/svm/hyperv.h
@@ -25,4 +25,6 @@ static inline void nested_svm_hv_update_vm_vp_ids(struct kvm_vcpu *vcpu)
hv_vcpu->nested.vp_id = hve->hv_vp_id;
}

+void svm_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu);
+
#endif /* __ARCH_X86_KVM_SVM_HYPERV_H__ */
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 45bab740f3f0..05889d5a8629 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1721,4 +1721,5 @@ struct kvm_x86_nested_ops svm_nested_ops = {
.get_nested_state_pages = svm_get_nested_state_pages,
.get_state = svm_get_nested_state,
.set_state = svm_set_nested_state,
+ .hv_inject_synthetic_vmexit_post_tlb_flush = svm_hv_inject_synthetic_vmexit_post_tlb_flush,
};
diff --git a/arch/x86/kvm/vmx/hyperv.c b/arch/x86/kvm/vmx/hyperv.c
index 5e239158174e..f05464db4fdc 100644
--- a/arch/x86/kvm/vmx/hyperv.c
+++ b/arch/x86/kvm/vmx/hyperv.c
@@ -506,3 +506,7 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu,

return 0;
}
+
+void vmx_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu)
+{
+}
diff --git a/arch/x86/kvm/vmx/hyperv.h b/arch/x86/kvm/vmx/hyperv.h
index 99a151af7a81..8efaffe9215b 100644
--- a/arch/x86/kvm/vmx/hyperv.h
+++ b/arch/x86/kvm/vmx/hyperv.h
@@ -243,5 +243,6 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu,
uint16_t *vmcs_version);
void nested_evmcs_filter_control_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata);
int nested_evmcs_check_controls(struct vmcs12 *vmcs12);
+void vmx_hv_inject_synthetic_vmexit_post_tlb_flush(struct kvm_vcpu *vcpu);

#endif /* __KVM_X86_VMX_HYPERV_H */
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 7a4260416d88..a89b8e6f90f3 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -6996,4 +6996,5 @@ struct kvm_x86_nested_ops vmx_nested_ops = {
.write_log_dirty = nested_vmx_write_pml_buffer,
.enable_evmcs = nested_enable_evmcs,
.get_evmcs_version = nested_get_evmcs_version,
+ .hv_inject_synthetic_vmexit_post_tlb_flush = vmx_hv_inject_synthetic_vmexit_post_tlb_flush,
};
--
2.37.3

2022-10-21 16:26:49

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 27/46] KVM: x86: Make kvm_hv_get_assist_page() return 0/-errno

Convert kvm_hv_get_assist_page() to return 'int' and propagate possible
errors from kvm_read_guest_cached().

Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 8 ++++----
arch/x86/kvm/hyperv.h | 2 +-
arch/x86/kvm/vmx/hyperv.c | 2 +-
3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 90f37e58a9ed..404e1a968b02 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -900,15 +900,15 @@ bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvm_hv_assist_page_enabled);

-bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu)
+int kvm_hv_get_assist_page(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);

if (!hv_vcpu || !kvm_hv_assist_page_enabled(vcpu))
- return false;
+ return -EFAULT;

- return !kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
- &hv_vcpu->vp_assist_page, sizeof(struct hv_vp_assist_page));
+ return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data,
+ &hv_vcpu->vp_assist_page, sizeof(struct hv_vp_assist_page));
}
EXPORT_SYMBOL_GPL(kvm_hv_get_assist_page);

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index 81313e418b80..5157622c2fb3 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -108,7 +108,7 @@ int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages);
void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu);

bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu);
-bool kvm_hv_get_assist_page(struct kvm_vcpu *vcpu);
+int kvm_hv_get_assist_page(struct kvm_vcpu *vcpu);

static inline struct kvm_vcpu_hv_stimer *to_hv_stimer(struct kvm_vcpu *vcpu,
int timer_index)
diff --git a/arch/x86/kvm/vmx/hyperv.c b/arch/x86/kvm/vmx/hyperv.c
index 04a0bba58c7d..ae03d1fe0355 100644
--- a/arch/x86/kvm/vmx/hyperv.c
+++ b/arch/x86/kvm/vmx/hyperv.c
@@ -326,7 +326,7 @@ u64 nested_get_evmptr(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);

- if (unlikely(!kvm_hv_get_assist_page(vcpu)))
+ if (unlikely(kvm_hv_get_assist_page(vcpu)))
return EVMPTR_INVALID;

if (unlikely(!hv_vcpu->vp_assist_page.enlighten_vmentry))
--
2.37.3

2022-10-21 16:27:37

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 06/46] KVM: VMX: Rename "vmx/evmcs.{ch}" to "vmx/hyperv.{ch}"

To conform with SVM, rename VMX specific Hyper-V files from "evmcs.{ch}"
to "hyperv.{ch}". While Enlightened VMCS is a lion's share of these
files, some stuff (e.g. enlightened MSR bitmap, the upcoming Hyper-V
L2 TLB flush, ...) goes beyond that.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/Makefile | 2 +-
arch/x86/kvm/vmx/{evmcs.c => hyperv.c} | 3 +--
arch/x86/kvm/vmx/{evmcs.h => hyperv.h} | 8 +++++---
arch/x86/kvm/vmx/nested.c | 1 -
arch/x86/kvm/vmx/vmx.c | 1 -
arch/x86/kvm/vmx/vmx_ops.h | 2 +-
6 files changed, 8 insertions(+), 9 deletions(-)
rename arch/x86/kvm/vmx/{evmcs.c => hyperv.c} (99%)
rename arch/x86/kvm/vmx/{evmcs.h => hyperv.h} (98%)

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 30f244b64523..4412f0b8244c 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -22,7 +22,7 @@ kvm-$(CONFIG_X86_64) += mmu/tdp_iter.o mmu/tdp_mmu.o
kvm-$(CONFIG_KVM_XEN) += xen.o

kvm-intel-y += vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
- vmx/evmcs.o vmx/nested.o vmx/posted_intr.o
+ vmx/hyperv.o vmx/nested.o vmx/posted_intr.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 svm/sev.o
diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/hyperv.c
similarity index 99%
rename from arch/x86/kvm/vmx/evmcs.c
rename to arch/x86/kvm/vmx/hyperv.c
index d8b23c96d627..5e239158174e 100644
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/hyperv.c
@@ -3,9 +3,8 @@
#include <linux/errno.h>
#include <linux/smp.h>

-#include "../hyperv.h"
#include "../cpuid.h"
-#include "evmcs.h"
+#include "hyperv.h"
#include "vmcs.h"
#include "vmx.h"
#include "trace.h"
diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/hyperv.h
similarity index 98%
rename from arch/x86/kvm/vmx/evmcs.h
rename to arch/x86/kvm/vmx/hyperv.h
index 6f746ef3c038..99a151af7a81 100644
--- a/arch/x86/kvm/vmx/evmcs.h
+++ b/arch/x86/kvm/vmx/hyperv.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __KVM_X86_VMX_EVMCS_H
-#define __KVM_X86_VMX_EVMCS_H
+#ifndef __KVM_X86_VMX_HYPERV_H
+#define __KVM_X86_VMX_HYPERV_H

#include <linux/jump_label.h>

@@ -8,6 +8,8 @@
#include <asm/mshyperv.h>
#include <asm/vmx.h>

+#include "../hyperv.h"
+
#include "capabilities.h"
#include "vmcs.h"
#include "vmcs12.h"
@@ -242,4 +244,4 @@ int nested_enable_evmcs(struct kvm_vcpu *vcpu,
void nested_evmcs_filter_control_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata);
int nested_evmcs_check_controls(struct vmcs12 *vmcs12);

-#endif /* __KVM_X86_VMX_EVMCS_H */
+#endif /* __KVM_X86_VMX_HYPERV_H */
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 8f67a9c4a287..feab88a13026 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -7,7 +7,6 @@
#include <asm/mmu_context.h>

#include "cpuid.h"
-#include "evmcs.h"
#include "hyperv.h"
#include "mmu.h"
#include "nested.h"
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6b258d9cf53c..f7cf1352ca0f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -51,7 +51,6 @@

#include "capabilities.h"
#include "cpuid.h"
-#include "evmcs.h"
#include "hyperv.h"
#include "kvm_onhyperv.h"
#include "irq.h"
diff --git a/arch/x86/kvm/vmx/vmx_ops.h b/arch/x86/kvm/vmx/vmx_ops.h
index ec268df83ed6..f6f23c7397dc 100644
--- a/arch/x86/kvm/vmx/vmx_ops.h
+++ b/arch/x86/kvm/vmx/vmx_ops.h
@@ -6,7 +6,7 @@

#include <asm/vmx.h>

-#include "evmcs.h"
+#include "hyperv.h"
#include "vmcs.h"
#include "../x86.h"

--
2.37.3

2022-10-21 16:27:43

by Vitaly Kuznetsov

[permalink] [raw]
Subject: [PATCH v12 29/46] KVM: x86: Expose Hyper-V L2 TLB flush feature

With both nSVM and nVMX implementations in place, KVM can now expose
Hyper-V L2 TLB flush feature to userspace.

Reviewed-by: Maxim Levitsky <[email protected]>
Signed-off-by: Vitaly Kuznetsov <[email protected]>
---
arch/x86/kvm/hyperv.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 404e1a968b02..2464c21feec9 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -2772,6 +2772,7 @@ int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,

case HYPERV_CPUID_NESTED_FEATURES:
ent->eax = evmcs_ver;
+ ent->eax |= HV_X64_NESTED_DIRECT_FLUSH;
ent->eax |= HV_X64_NESTED_MSR_BITMAP;
ent->ebx |= HV_X64_NESTED_EVMCS1_PERF_GLOBAL_CTRL;
break;
--
2.37.3

2022-10-26 22:26:34

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 36/46] KVM: selftests: Drop helpers to read/write page table entries

On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> From: Sean Christopherson <[email protected]>
>
> Drop vm_{g,s}et_page_table_entry() and instead expose the "inner"
> helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the
> PTE, i.e. let tests directly modify PTEs instead of bouncing through
> helpers that just make life difficult.
>
> Opportunsitically use BIT_ULL() in emulator_error_test, and use the
> MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the
> same value.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <[email protected]>

Missing your SOB, though maybe Paolo will merge my series first and make this a
moot point :-)

2022-10-26 22:29:35

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 44/46] KVM: selftests: evmcs_test: Introduce L2 TLB flush test

On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> @@ -48,6 +49,8 @@ static inline void rdmsr_gs_base(void)
>
> void l2_guest_code(void)
> {
> + u64 unused;
> +
> GUEST_SYNC(7);
>
> GUEST_SYNC(8);
> @@ -64,15 +67,33 @@ void l2_guest_code(void)
> vmcall();
> rdmsr_gs_base(); /* intercepted */
>
> + /* L2 TLB flush tests */
> + hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE | HV_HYPERCALL_FAST_BIT, 0x0,
> + HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES | HV_FLUSH_ALL_PROCESSORS);
> + rdmsr_fs_base();
> + /*
> + * Note: hypercall status (RAX) is not preserved correctly by L1 after
> + * synthetic vmexit, use unchecked version.
> + */
> + __hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE | HV_HYPERCALL_FAST_BIT, 0x0,
> + HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES | HV_FLUSH_ALL_PROCESSORS,
> + &unused);
> + /* Make sure we're not issuing Hyper-V TLB flush call again */
> + __asm__ __volatile__ ("mov $0xdeadbeef, %rcx");

This needs a clobber. It won't cause problems in the current code, but it will
make someone really sad if they add more code after this.

Using %ecx instead of %rcx will also suffice, 32-bit accesses clear bits 63:32.

Even better, if a "nop" isn't required to get the compiler to emit preamble, would
be to load ECX through an input constraint, that way the compiler "knows" the value
of ECX and can optimize for it (though it's extremely unlikely 0xdeadbeef will be
a useful value).

Actually, not setting RCX in vmcall() is a nasty bug waiting to happen, e.g. if
RCX just happens to contain a value that gets routed to L0.

Rather than handle this as a one-off, can you insert a prep patch to have the
common vmcall() stuff RCX with a "safe" value?

Related side topic, rdmsr_{f,g}s_base() should also use input constraints, and
should use a proper #define for the MSRs. Also, why earth do those clobber all GPRs?
Oooh, because they get routed to L1 and L1 doesn't preserve GPRs.

Related side topic #2, KVM's kvm_xen_hypercall() is broken, it checks the wrong
input register for 64-bit (checks RAX instead of RCX). Not sure that's even a
fixable bug though.

2022-10-26 22:30:01

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 45/46] KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test

On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> Enable Hyper-V L2 TLB flush and check that Hyper-V TLB flush hypercalls
> from L2 don't exit to L1 unless 'TlbLockCount' is set in the Partition
> assist page.
>
> Signed-off-by: Vitaly Kuznetsov <[email protected]>
> ---
> .../selftests/kvm/include/x86_64/svm.h | 4 ++
> .../selftests/kvm/x86_64/hyperv_svm_test.c | 61 +++++++++++++++++--
> 2 files changed, 60 insertions(+), 5 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/include/x86_64/svm.h b/tools/testing/selftests/kvm/include/x86_64/svm.h
> index 483e6ae12f69..4803e1056055 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/svm.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/svm.h
> @@ -76,6 +76,10 @@ struct hv_vmcb_enlightenments {
> */
> #define HV_VMCB_NESTED_ENLIGHTENMENTS (1U << 31)
>
> +/* Synthetic VM-Exit */
> +#define HV_SVM_EXITCODE_ENL 0xf0000000
> +#define HV_SVM_ENL_EXITCODE_TRAP_AFTER_FLUSH (1)
> +
> struct __attribute__ ((__packed__)) vmcb_control_area {
> u32 intercept_cr;
> u32 intercept_dr;
> diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
> index 1c3fc38b4f15..edb779615a79 100644
> --- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
> @@ -25,6 +25,8 @@
>
> void l2_guest_code(void)
> {
> + u64 unused;
> +
> GUEST_SYNC(3);
> /* Exit to L1 */
> vmmcall();
> @@ -38,11 +40,30 @@ void l2_guest_code(void)
>
> GUEST_SYNC(5);
>
> + /* L2 TLB flush tests */
> + hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE |
> + HV_HYPERCALL_FAST_BIT, 0x0,
> + HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
> + HV_FLUSH_ALL_PROCESSORS);
> + rdmsr(MSR_FS_BASE);

Why doesn't the SVM test need to clobber GPRs?

> + /*
> + * Note: hypercall status (RAX) is not preserved correctly by L1 after
> + * synthetic vmexit, use unchecked version.
> + */
> + __hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE |
> + HV_HYPERCALL_FAST_BIT, 0x0,
> + HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES |
> + HV_FLUSH_ALL_PROCESSORS, &unused);
> + /* Make sure we're not issuing Hyper-V TLB flush call again */
> + __asm__ __volatile__ ("mov $0xdeadbeef, %rcx");

Heh, and a patch to vmmcall() itself "safe"...

> +
> /* Done, exit to L1 and never come back. */
> vmmcall();
> }

2022-10-26 22:30:44

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 13/46] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> To handle L2 TLB flush requests, KVM needs to translate the specified
> L2 GPA to L1 GPA to read hypercall arguments from there.
>
> No functional change as KVM doesn't handle VMCALL/VMMCALL from L2 yet.
>
> Reviewed-by: Maxim Levitsky <[email protected]>
> Signed-off-by: Vitaly Kuznetsov <[email protected]>
> ---
> arch/x86/kvm/hyperv.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index fca9c51891f5..df1efb821eb0 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -23,6 +23,7 @@
> #include "ioapic.h"
> #include "cpuid.h"
> #include "hyperv.h"
> +#include "mmu.h"
> #include "xen.h"
>
> #include <linux/cpu.h>
> @@ -1908,6 +1909,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> */
> BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
>
> + if (!hc->fast && is_guest_mode(vcpu)) {

Please add a comment explaining why only "slow" hypercalls need to translate the
GPA from L2=>L1.

With a comment (and assuming this isn't a bug),

Reviewed-by: Sean Christopherson <[email protected]>

2022-10-26 22:31:27

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 00/46] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features

On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> KVM: selftests: evmcs_test: Introduce L2 TLB flush test
> KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test

Except for these two (patches 44 and 45),

Reviewed-by: Sean Christopherson <[email protected]>

2022-10-26 22:34:06

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 00/46] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features

On Wed, Oct 26, 2022, Sean Christopherson wrote:
> On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> > KVM: selftests: evmcs_test: Introduce L2 TLB flush test
> > KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test
>
> Except for these two (patches 44 and 45),
>
> Reviewed-by: Sean Christopherson <[email protected]>

Actually, easiest thing is probably for Paolo to queue everything through 43
(with a comment in patch 13 about the GPA translation), and then you can send a
new version containing only the stragglers.

2022-10-26 22:44:38

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 34/46] KVM: selftests: Fill in vm->vpages_mapped bitmap in virt_map() too

On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> Similar to vm_vaddr_alloc(), virt_map() needs to reflect the mapping
> in vm->vpages_mapped.
>
> While on it, remove unneeded code wraping in vm_vaddr_alloc().

"wrapping", this is dangerously close to getting someone fired ;-)

2022-10-27 09:00:09

by Vitaly Kuznetsov

[permalink] [raw]
Subject: Re: [PATCH v12 13/46] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

Sean Christopherson <[email protected]> writes:

> On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
>> To handle L2 TLB flush requests, KVM needs to translate the specified
>> L2 GPA to L1 GPA to read hypercall arguments from there.
>>
>> No functional change as KVM doesn't handle VMCALL/VMMCALL from L2 yet.
>>
>> Reviewed-by: Maxim Levitsky <[email protected]>
>> Signed-off-by: Vitaly Kuznetsov <[email protected]>
>> ---
>> arch/x86/kvm/hyperv.c | 7 +++++++
>> 1 file changed, 7 insertions(+)
>>
>> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
>> index fca9c51891f5..df1efb821eb0 100644
>> --- a/arch/x86/kvm/hyperv.c
>> +++ b/arch/x86/kvm/hyperv.c
>> @@ -23,6 +23,7 @@
>> #include "ioapic.h"
>> #include "cpuid.h"
>> #include "hyperv.h"
>> +#include "mmu.h"
>> #include "xen.h"
>>
>> #include <linux/cpu.h>
>> @@ -1908,6 +1909,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
>> */
>> BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
>>
>> + if (!hc->fast && is_guest_mode(vcpu)) {
>
> Please add a comment explaining why only "slow" hypercalls need to translate the
> GPA from L2=>L1.
>
> With a comment (and assuming this isn't a bug),

This is intended,

For "slow" hypercalls 'hc->ingpa' is the GPA (or an 'nGPA' -- thus the
patch) in guest memory where hypercall parameters are placed, kvm reads
them with kvm_read_guest() later. For "fast" hypercalls 'ingpa' is a
misnomer as it is not an address but the first parameter (in the 'tlb
flush' case it's 'address space id' which we currently don't
analyze). We may want to add a union in 'struct kvm_hv_hcall' to make
this explicit.

The comment I'm thinking of would be:

"
/*
* 'Slow' hypercall's first parameter is the address in guest's memory where
* hypercall parameters are placed. This is either a GPA or a nested GPA when
* KVM is handling the call from L2 ('direct' TLB flush), translate the address
* here so the memory can be uniformly read with kvm_read_guest().
*/
"

>
> Reviewed-by: Sean Christopherson <[email protected]>
>

--
Vitaly


2022-10-27 22:19:59

by Sean Christopherson

[permalink] [raw]
Subject: Re: [PATCH v12 13/46] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

On Thu, Oct 27, 2022, Vitaly Kuznetsov wrote:
> Sean Christopherson <[email protected]> writes:
>
> > On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
> >> @@ -1908,6 +1909,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> >> */
> >> BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
> >>
> >> + if (!hc->fast && is_guest_mode(vcpu)) {
> >
> > Please add a comment explaining why only "slow" hypercalls need to translate the
> > GPA from L2=>L1.
> >
> > With a comment (and assuming this isn't a bug),
>
> This is intended,
>
> For "slow" hypercalls 'hc->ingpa' is the GPA (or an 'nGPA' -- thus the
> patch) in guest memory where hypercall parameters are placed, kvm reads
> them with kvm_read_guest() later. For "fast" hypercalls 'ingpa' is a
> misnomer as it is not an address but the first parameter (in the 'tlb
> flush' case it's 'address space id' which we currently don't
> analyze). We may want to add a union in 'struct kvm_hv_hcall' to make
> this explicit.

Ya, a union would be helpful. I'm pretty sure at some point I knew the "fast"
ingpa isn't actually a GPA, but obviously forgot that detail.

2022-10-31 09:36:47

by Vitaly Kuznetsov

[permalink] [raw]
Subject: Re: [PATCH v12 00/46] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features

Sean Christopherson <[email protected]> writes:

> On Wed, Oct 26, 2022, Sean Christopherson wrote:
>> On Fri, Oct 21, 2022, Vitaly Kuznetsov wrote:
>> > KVM: selftests: evmcs_test: Introduce L2 TLB flush test
>> > KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test
>>
>> Except for these two (patches 44 and 45),
>>
>> Reviewed-by: Sean Christopherson <[email protected]>

Thanks! I'll take a look at 44/45 shortly.

>
> Actually, easiest thing is probably for Paolo to queue everything through 43
> (with a comment in patch 13 about the GPA translation), and then you can send a
> new version containing only the stragglers.

Paolo,

do you want to follow this path or do you expect the full 'v13' from me?

--
Vitaly


2022-11-01 15:57:47

by Vitaly Kuznetsov

[permalink] [raw]
Subject: Re: [PATCH v12 00/46] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features

Vitaly Kuznetsov <[email protected]> writes:

>
> Paolo,
>
> do you want to follow this path or do you expect the full 'v13' from me?

v13 it is :-) I've added all the tags and addressed the remaining
feedback (a typo fixed + a comment added).

--
Vitaly