TDX stands for Trust Domain Extensions which isolates VMs from the
virtual-machine manager (VMM)/hypervisor and any other software on the
platform.
Intel has recently submitted a set of RFC patches for KVM support for
TDX and more information can be found on the latest TDX Support
Patches: https://lkml.org/lkml/2021/7/2/558
Due to the nature of the confidential computing environment that TDX
provides, it is very difficult to verify/test the KVM support. TDX
requires UEFI and the guest kernel to be enlightened which are all under
development.
We are working on a set of selftests to close this gap and be able to
verify the KVM functionality to support TDX lifecycle and GHCI [1]
interface.
We are looking for any feedback on:
- Patch series itself
- Any suggestion on how we should approach testing TDX functionality.
Does selftests seems reasonable or should we switch to using KVM
unit tests. I would be happy to get some perspective on how KVM unit
tests can help us more.
- Any test case or scenario that we should add.
- Anything else I have not thought of yet.
Current patch series provide the following capabilities:
- Provide helper functions to create a TD (Trusted Domain) using the KVM
ioctls
- Provide helper functions to create a guest image that can include any
testing code
- Provide helper functions and wrapper functions to write testing code
using GHCI interface
- Add a test case that verifies TDX life cycle
- Add a test case that verifies TDX GHCI port IO
TODOs:
- Use existing function to create page tables dynamically
(ie __virt_pg_map())
- Remove arbitrary defined magic numbers for data structure offsets
- Add TDVMCALL for error reporting
- Add additional test cases as some listed below
- Add #VE handlers to help testing more complicated test cases
Other test cases that we are planning to add:
(with credit to [email protected])
VM call interface Input Output Result
GetTdVmCallInfo R12=0 None VMCALL_SUCCESS
MapGPA Map private page (GPA.S=0) VMCALL_SUCCESS
MapGPA Map shared page (GPA.S=1) VMCALL_SUCCESS
MapGPA Map already private page as private VMCALL_INVALID_OPERAND
MapGPA Map already shared page as shared VMCALL_INVALID_OPERAND
GetQuote
ReportFatalError
SetupEventNotifyInterrupt Valid interrupt value (32:255) VMCALL_SUCCESS
SetupEventNotifyInterrupt Invalid value (>255) VMCALL_INVALID_OPERAND
Instruction.CPUID R12(EAX)=1, R13(ECX)=0 EBX[8:15]=0x8
EBX[16:23]=X
EBX[24:31]=vcpu_id
ECX[0]=1
ECX[12]=Y
Instruction.CPUID R12(EAX)=1, R13(ECX)=4 VMCALL_INVALID_OPERAND
VE.RequestMMIO
Instruction.HLT VMCALL_SUCCESS
Instruction.IO Read/Write 1/2/4 bytes VMCALL_SUCCESS
Instruction.IO Read/Write 3 bytes VMCALL_INVALID_OPERAND
Instruction.RDMSR Accessible register R11=msr_value VMCALL_SUCCESS
Inaccessible register VMCALL_INVALID_OPERAND
Instruction.RDMSR Accessible register VMCALL_SUCCESS
Inaccessible register VMCALL_INVALID_OPERAND
INSTRUCTION.PCONFIG
[1] Intel TDX Guest-Hypervisor Communication Interface
https://software.intel.com/content/dam/develop/external/us/en/documents/intel-tdx-guest-hypervisor-communication-interface.pdf
Erdem Aktas (4):
KVM: selftests: Add support for creating non-default type VMs
KVM: selftest: Add helper functions to create TDX VMs
KVM: selftest: Adding TDX life cycle test.
KVM: selftest: Adding test case for TDX port IO
tools/testing/selftests/kvm/Makefile | 6 +-
.../testing/selftests/kvm/include/kvm_util.h | 1 +
.../selftests/kvm/include/x86_64/processor.h | 5 +
tools/testing/selftests/kvm/lib/kvm_util.c | 29 +-
.../selftests/kvm/lib/x86_64/processor.c | 23 ++
tools/testing/selftests/kvm/lib/x86_64/tdx.h | 220 ++++++++++++
.../selftests/kvm/lib/x86_64/tdx_lib.c | 314 ++++++++++++++++++
.../selftests/kvm/x86_64/tdx_vm_tests.c | 209 ++++++++++++
8 files changed, 800 insertions(+), 7 deletions(-)
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx.h
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx_lib.c
create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
--
2.32.0.432.gabb21c7263-goog
Adding a test to verify TDX lifecycle by creating a TD and running a
dummy TDVMCALL<INSTRUCTION.IO> inside it.
Signed-off-by: Erdem Aktas <[email protected]>
Reviewed-by: Sean Christopherson <[email protected]>
Reviewed-by: Peter Gonda <[email protected]>
Reviewed-by: Marc Orr <[email protected]>
Reviewed-by: Sagi Shahar <[email protected]>
---
tools/testing/selftests/kvm/Makefile | 1 +
tools/testing/selftests/kvm/lib/x86_64/tdx.h | 131 ++++++++++++++++++
.../selftests/kvm/x86_64/tdx_vm_tests.c | 102 ++++++++++++++
3 files changed, 234 insertions(+)
create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index d84c09b5e..259be634c 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -72,6 +72,7 @@ TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus
TEST_GEN_PROGS_x86_64 += memslot_modification_stress_test
TEST_GEN_PROGS_x86_64 += set_memory_region_test
TEST_GEN_PROGS_x86_64 += steal_time
TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
+TEST_GEN_PROGS_x86_64 += x86_64/tdx_vm_tests
TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx.h b/tools/testing/selftests/kvm/lib/x86_64/tdx.h
index 6e3e8384e..395be3c81 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/tdx.h
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx.h
@@ -86,4 +86,135 @@ void prepare_source_image(struct kvm_vm *vm, void *guest_code,
size_t guest_code_size,
uint64_t guest_code_signature);
+/*
+ * Generic TDCALL function that can be used to communicate with TDX module or
+ * VMM.
+ * Input operands: rax, rbx, rcx, rdx, r8-r15, rbp, rsi, rdi
+ * Output operands: rax, r8-r15, rbx, rdx, rdi, rsi
+ * rcx is actually a bitmap to tell TDX module which register values will be
+ * exposed to the VMM.
+ * XMM0-XMM15 registers can be used as input operands but the current
+ * implementation does not support it yet.
+ */
+static inline void tdcall(struct kvm_regs *regs)
+{
+ asm volatile (
+ "mov %13, %%rax;\n\t"
+ "mov %14, %%rbx;\n\t"
+ "mov %15, %%rcx;\n\t"
+ "mov %16, %%rdx;\n\t"
+ "mov %17, %%r8;\n\t"
+ "mov %18, %%r9;\n\t"
+ "mov %19, %%r10;\n\t"
+ "mov %20, %%r11;\n\t"
+ "mov %21, %%r12;\n\t"
+ "mov %22, %%r13;\n\t"
+ "mov %23, %%r14;\n\t"
+ "mov %24, %%r15;\n\t"
+ "mov %25, %%rbp;\n\t"
+ "mov %26, %%rsi;\n\t"
+ "mov %27, %%rdi;\n\t"
+ ".byte 0x66, 0x0F, 0x01, 0xCC;\n\t"
+ "mov %%rax, %0;\n\t"
+ "mov %%rbx, %1;\n\t"
+ "mov %%rdx, %2;\n\t"
+ "mov %%r8, %3;\n\t"
+ "mov %%r9, %4;\n\t"
+ "mov %%r10, %5;\n\t"
+ "mov %%r11, %6;\n\t"
+ "mov %%r12, %7;\n\t"
+ "mov %%r13, %8;\n\t"
+ "mov %%r14, %9;\n\t"
+ "mov %%r15, %10;\n\t"
+ "mov %%rsi, %11;\n\t"
+ "mov %%rdi, %12;\n\t"
+ : "=m" (regs->rax), "=m" (regs->rbx), "=m" (regs->rdx),
+ "=m" (regs->r8), "=m" (regs->r9), "=m" (regs->r10),
+ "=m" (regs->r11), "=m" (regs->r12), "=m" (regs->r13),
+ "=m" (regs->r14), "=m" (regs->r15), "=m" (regs->rsi),
+ "=m" (regs->rdi)
+ : "m" (regs->rax), "m" (regs->rbx), "m" (regs->rcx),
+ "m" (regs->rdx), "m" (regs->r8), "m" (regs->r9),
+ "m" (regs->r10), "m" (regs->r11), "m" (regs->r12),
+ "m" (regs->r13), "m" (regs->r14), "m" (regs->r15),
+ "m" (regs->rbp), "m" (regs->rsi), "m" (regs->rdi)
+ : "rax", "rbx", "rcx", "rdx", "r8", "r9", "r10", "r11",
+ "r12", "r13", "r14", "r15", "rbp", "rsi", "rdi");
+}
+
+
+/*
+ * Do a TDVMCALL IO request
+ *
+ * Input Args:
+ * port - IO port to do read/write
+ * size - Number of bytes to read/write. 1=1byte, 2=2bytes, 4=4bytes.
+ * write - 1=IO write 0=IO read
+ * data - pointer for the data to write
+ *
+ * Output Args:
+ * data - pointer for data to be read
+ *
+ * Return:
+ * On success, return 0. For Invalid-IO-Port error, returns -1.
+ *
+ * Does an IO operation using the following tdvmcall interface.
+ *
+ * TDG.VP.VMCALL<Instruction.IO>-Input Operands
+ * R11 30 for IO
+ *
+ * R12 Size of access. 1=1byte, 2=2bytes, 4=4bytes.
+ * R13 Direction. 0=Read, 1=Write.
+ * R14 Port number
+ * R15 Data to write, if R13 is 1.
+ *
+ * TDG.VP.VMCALL<Instruction.IO>-Output Operands
+ * R10 TDG.VP.VMCALL-return code.
+ * R11 Data to read, if R13 is 0.
+ *
+ * TDG.VP.VMCALL<Instruction.IO>-Status Codes
+ * Error Code Value Description
+ * TDG.VP.VMCALL_SUCCESS 0x0 TDG.VP.VMCALL is successful
+ * TDG.VP.VMCALL_INVALID_OPERAND 0x80000000 00000000 Invalid-IO-Port access
+ */
+static inline int tdvmcall_io(uint64_t port, uint64_t size,
+ uint64_t write, uint64_t *data)
+{
+ struct kvm_regs regs;
+
+ memset(®s, 0, sizeof(regs));
+ regs.r11 = 30;
+ regs.r12 = size;
+ regs.r13 = write;
+ regs.r14 = port;
+ if (write)
+ regs.r15 = *data;
+ /* TODO: update the bitmap register with only the relavent registers */
+ regs.rcx = 0xFC00;
+ tdcall(®s);
+ if (!write)
+ *data = regs.r11;
+ return regs.r10;
+}
+
+
+#define TDX_FUNCTION_SIZE(name) ((uint64_t)&__stop_sec_ ## name -\
+ (uint64_t)&__start_sec_ ## name) \
+
+#define TDX_GUEST_FUNCTION__(name, section_name) \
+extern char *__start_sec_ ## name ; \
+extern char *__stop_sec_ ## name ; \
+static void \
+__attribute__((__flatten__, section(section_name))) name(void *arg)
+
+
+#define STRINGIFY2(x) #x
+#define STRINGIFY(x) STRINGIFY2(x)
+#define CONCAT2(a, b) a##b
+#define CONCAT(a, b) CONCAT2(a, b)
+
+
+#define TDX_GUEST_FUNCTION(name) \
+TDX_GUEST_FUNCTION__(name, STRINGIFY(CONCAT(sec_, name)))
+
#endif // KVM_LIB_TDX_H_
diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
new file mode 100644
index 000000000..da7ea67b1
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <fcntl.h>
+#include <limits.h>
+#include <kvm_util.h>
+#include "../lib/kvm_util_internal.h"
+#include "../lib/x86_64/tdx.h"
+#include <linux/kvm.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <test_util.h>
+#include <unistd.h>
+#include <processor.h>
+#include <time.h>
+#include <sys/mman.h>
+#include<sys/wait.h>
+
+/*
+ * There might be multiple tests we are running and if one test fails, it will
+ * prevent the subsequent tests to run due to how tests are failing with
+ * TEST_ASSERT function. The run_in_new_process function will run a test in a
+ * new process context and wait for it to finish or fail to prevent TEST_ASSERT
+ * to kill the main testing process.
+ */
+void run_in_new_process(void (*func)(void))
+{
+ if (fork() == 0) {
+ func();
+ exit(0);
+ }
+ wait(NULL);
+}
+
+/*
+ * Verify that the TDX is supported by the KVM.
+ */
+bool is_tdx_enabled(void)
+{
+ return !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_TDX_VM));
+}
+
+/*
+ * Do a dummy io exit to verify that the TD has been initialized correctly and
+ * guest can run some code inside.
+ */
+TDX_GUEST_FUNCTION(guest_dummy_exit)
+{
+ uint64_t data;
+
+ data = 0xAB;
+ tdvmcall_io(TDX_TEST_PORT, 1, 1, &data);
+}
+
+/*
+ * TD lifecycle test will create a TD which runs a dumy IO exit to verify that
+ * the guest TD has been created correctly.
+ */
+void verify_td_lifecycle(void)
+{
+ struct kvm_vm *vm;
+ struct kvm_run *run;
+
+ printf("Verifying TD lifecycle:\n");
+ /* Create a TD VM with no memory.*/
+ vm = __vm_create(VM_MODE_DEFAULT, 0, O_RDWR, KVM_X86_TDX_VM);
+
+ /* Allocate TD guest memory and initialize the TD.*/
+ initialize_td(vm);
+
+ /* Initialize the TD vcpu and copy the test code to the guest memory.*/
+ vm_vcpu_add_tdx(vm, 0);
+
+ /* Setup and initialize VM memory */
+ prepare_source_image(vm, guest_dummy_exit,
+ TDX_FUNCTION_SIZE(guest_dummy_exit), 0);
+ finalize_td_memory(vm);
+
+ run = vcpu_state(vm, 0);
+ vcpu_run(vm, 0);
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason));
+
+ kvm_vm_free(vm);
+ printf("\t ... PASSED\n");
+}
+int main(int argc, char **argv)
+{
+ if (!is_tdx_enabled()) {
+ printf("TDX is not supported by the KVM\n"
+ "Skipping the TDX tests.\n");
+ return 0;
+ }
+
+ run_in_new_process(&verify_td_lifecycle);
+
+ return 0;
+}
--
2.32.0.432.gabb21c7263-goog
Verifies TDVMCALL<INSTRUCTION.IO> READ and WRITE operations.
Signed-off-by: Erdem Aktas <[email protected]>
Reviewed-by: Sean Christopherson <[email protected]>
Reviewed-by: Peter Gonda <[email protected]>
Reviewed-by: Marc Orr <[email protected]>
Reviewed-by: Sagi Shahar <[email protected]>
---
.../selftests/kvm/x86_64/tdx_vm_tests.c | 107 ++++++++++++++++++
1 file changed, 107 insertions(+)
diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
index da7ea67b1..7b0b4b378 100644
--- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
@@ -88,6 +88,112 @@ void verify_td_lifecycle(void)
kvm_vm_free(vm);
printf("\t ... PASSED\n");
}
+
+/*
+ * Verifies IO functionality by writing a |value| to a predefined port.
+ * Verifies that the read value is |value| + 1 from the same port.
+ * If all the tests are passed then write a value to port TDX_TEST_PORT
+ */
+TDX_GUEST_FUNCTION(guest_io_exit)
+{
+ uint64_t data_out, data_in, delta;
+
+ data_out = 0xAB;
+ tdvmcall_io(TDX_TEST_PORT, 1, 1, &data_out);
+ tdvmcall_io(TDX_TEST_PORT, 1, 0, &data_in);
+ delta = data_in - data_out - 1;
+ tdvmcall_io(TDX_TEST_PORT, 1, 1, &delta);
+}
+
+void verify_td_ioexit(void)
+{
+ struct kvm_vm *vm;
+ struct kvm_run *run;
+ uint32_t port_data;
+
+ printf("Verifying TD IO Exit:\n");
+ /* Create a TD VM with no memory.*/
+ vm = __vm_create(VM_MODE_DEFAULT, 0, O_RDWR, KVM_X86_TDX_VM);
+
+ /* Allocate TD guest memory and initialize the TD.*/
+ initialize_td(vm);
+
+ /* Initialize the TD vcpu and copy the test code to the guest memory.*/
+ vm_vcpu_add_tdx(vm, 0);
+
+ /* Setup and initialize VM memory */
+ prepare_source_image(vm, guest_io_exit,
+ TDX_FUNCTION_SIZE(guest_io_exit), 0);
+ finalize_td_memory(vm);
+
+ run = vcpu_state(vm, 0);
+
+ /* Wait for guest to do a IO write */
+ vcpu_run(vm, 0);
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason));
+
+ TEST_ASSERT((run->exit_reason == KVM_EXIT_IO)
+ && (run->io.port == TDX_TEST_PORT)
+ && (run->io.size == 1)
+ && (run->io.direction == 1),
+ "Got an unexpected IO exit values: %u (%s) %d %d %d\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason),
+ run->io.port, run->io.size, run->io.direction);
+ port_data = *(uint8_t *)((void *)run + run->io.data_offset);
+
+ printf("\t ... IO WRITE: OK\n");
+ /*
+ * Wait for the guest to do a IO read. Provide the previos written data
+ * + 1 back to the guest
+ */
+ vcpu_run(vm, 0);
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason));
+
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO &&
+ run->io.port == TDX_TEST_PORT &&
+ run->io.size == 1 &&
+ run->io.direction == 0,
+ "Got an unexpected IO exit values: %u (%s) %d %d %d\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason),
+ run->io.port, run->io.size, run->io.direction);
+ *(uint8_t *)((void *)run + run->io.data_offset) = port_data + 1;
+
+ printf("\t ... IO READ: OK\n");
+ /*
+ * Wait for the guest to do a IO write to the TDX_TEST_PORT with the
+ * value of 0. Any value other than 0 means, the guest has not able to
+ * read/write values correctly.
+ */
+ vcpu_run(vm, 0);
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "KVM_EXIT_IO is expected but got an exit_reason: %u (%s)\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason));
+
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO &&
+ run->io.port == TDX_TEST_PORT &&
+ run->io.size == 1 &&
+ run->io.direction == 1 &&
+ *(uint32_t *)((void *)run + run->io.data_offset) == 0,
+ "Got an unexpected IO exit values: %u (%s) %d %d %d %d\n",
+ run->exit_reason,
+ exit_reason_str(run->exit_reason),
+ run->io.port, run->io.size, run->io.direction,
+ *(uint32_t *)((void *)run + run->io.data_offset));
+
+ printf("\t ... IO verify read/write values: OK\n");
+ kvm_vm_free(vm);
+ printf("\t ... PASSED\n");
+}
+
int main(int argc, char **argv)
{
if (!is_tdx_enabled()) {
@@ -97,6 +203,7 @@ int main(int argc, char **argv)
}
run_in_new_process(&verify_td_lifecycle);
+ run_in_new_process(&verify_td_ioexit);
return 0;
}
--
2.32.0.432.gabb21c7263-goog
TDX requires additional IOCTLs to initialize VM and vCPUs, to add
private memory and to finalize the VM memory. Also additional utility
functions are provided to create a guest image that will include test code.
TDX enabled VM's memory is encrypted and cannot be modified or observed
by the VMM. We need to create a guest image that includes the testing
code.
When TDX is enabled, vCPUs will enter guest mode with 32 bit mode with
paging disabled. TDX requires the CPU to run on long mode with paging
enabled. The guest image should have transition code from 32 bit to 64
bit, enable paging and run the testing code. There has to be predifined
offset values for each data structure that will be used by the guest code.
The guest image layout is as following:
| Page Tables | GDTR | GDT | Stack | Testing Code | Transition Boot Code |
Guest image will be loaded to the bottom of the first 4GB of the memory.
Signed-off-by: Erdem Aktas <[email protected]>
Reviewed-by: Sean Christopherson <[email protected]>
Reviewed-by: Peter Gonda <[email protected]>
Reviewed-by: Marc Orr <[email protected]>
Reviewed-by: Sagi Shahar <[email protected]>
---
tools/testing/selftests/kvm/Makefile | 5 +-
.../selftests/kvm/include/x86_64/processor.h | 5 +
.../selftests/kvm/lib/x86_64/processor.c | 23 ++
tools/testing/selftests/kvm/lib/x86_64/tdx.h | 89 +++++
.../selftests/kvm/lib/x86_64/tdx_lib.c | 314 ++++++++++++++++++
5 files changed, 432 insertions(+), 4 deletions(-)
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx.h
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx_lib.c
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index b634926e2..d84c09b5e 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -34,7 +34,7 @@ ifeq ($(ARCH),s390)
endif
LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
-LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
+LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S /lib/x86_64/tdx_lib.c
LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index f5cb6fba6..62b26b50f 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -422,6 +422,11 @@ struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void);
void vcpu_set_hv_cpuid(struct kvm_vm *vm, uint32_t vcpuid);
struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vm *vm, uint32_t vcpuid);
+void vm_vcpu_add_tdx(struct kvm_vm *vm, uint32_t vcpuid);
+
+#define __stringify_1(x) #x
+#define __stringify(x) __stringify_1(x)
+
/*
* Basic CPU control in CR0
*/
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index a8906e60a..d97d40fa9 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -8,6 +8,7 @@
#include "test_util.h"
#include "kvm_util.h"
#include "../kvm_util_internal.h"
+#include "tdx.h"
#include "processor.h"
#ifndef NUM_INTERRUPTS
@@ -578,6 +579,28 @@ static void vcpu_setup(struct kvm_vm *vm, int vcpuid, int pgd_memslot, int gdt_m
vcpu_sregs_set(vm, vcpuid, &sregs);
}
+/*
+ * Adds a vCPU to a TD (Trusted Domain) with minimum defaults. It will not set
+ * up any general purpose registers as they will be initialized by the TDX. In
+ * TDX, vCPUs RIP is set to 0xFFFFFFF0. See Intel TDX EAS Section "Initial State
+ * of Guest GPRs" for more information on vCPUs initial register values when
+ * entering the TD first time.
+ *
+ * Input Args:
+ * vm - Virtual Machine
+ * vcpuid - The id of the VCPU to add to the VM.
+ */
+void vm_vcpu_add_tdx(struct kvm_vm *vm, uint32_t vcpuid)
+{
+ struct kvm_mp_state mp_state;
+
+ vm_vcpu_add(vm, vcpuid);
+ initialize_td_vcpu(vm, vcpuid);
+
+ mp_state.mp_state = 0;
+ vcpu_set_mp_state(vm, vcpuid, &mp_state);
+}
+
void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
{
struct kvm_mp_state mp_state;
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx.h b/tools/testing/selftests/kvm/lib/x86_64/tdx.h
new file mode 100644
index 000000000..6e3e8384e
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef KVM_LIB_TDX_H_
+#define KVM_LIB_TDX_H_
+
+#include <kvm_util.h>
+#include "../kvm_util_internal.h"
+
+/*
+ * Max page size for the guest image.
+ */
+#define TDX_GUEST_MAX_NR_PAGES 10000
+#define PAGE_SIZE 4096
+
+/*
+ * Page Table Address used when paging is enabled.
+ */
+#define TDX_GUEST_PT_FIXED_ADDR (0xFFFFFFFF -\
+ (TDX_GUEST_MAX_NR_PAGES * PAGE_SIZE) + 1)
+
+/*
+ * Max Page Table Size
+ * To map 4GB memory region with 2MB pages, there needs to be 1 page for PML4,
+ * 1 Page for PDPT, 4 pages for PD. Reserving 6 pages for PT.
+ */
+#define TDX_GUEST_NR_PT_PAGES (1 + 1 + 4)
+
+/*
+ * Predefined GDTR values.
+ */
+#define TDX_GUEST_GDTR_ADDR (TDX_GUEST_PT_FIXED_ADDR + (TDX_GUEST_NR_PT_PAGES *\
+ PAGE_SIZE))
+#define TDX_GUEST_GDTR_BASE (TDX_GUEST_GDTR_ADDR + PAGE_SIZE)
+#define TDX_GUEST_LINEAR_CODE64_SEL 0x38
+
+#define TDX_GUEST_STACK_NR_PAGES (3)
+#define TDX_GUEST_STACK_BASE (TDX_GUEST_GDTR_BASE + (TDX_GUEST_STACK_NR_PAGES *\
+ PAGE_SIZE) - 1)
+/*
+ * Reserving some pages to copy the test code. This is an arbitrary number for
+ * now to simplify to guest image layout calculation.
+ * TODO: calculate the guest code dynamcially.
+ */
+#define TDX_GUEST_CODE_ENTRY (TDX_GUEST_GDTR_BASE + (TDX_GUEST_STACK_NR_PAGES *\
+ PAGE_SIZE))
+
+#define KVM_MAX_CPUID_ENTRIES 256
+
+/*
+ * TODO: Move page attributes to processor.h file.
+ */
+#define _PAGE_PRESENT (1UL<<0) /* is present */
+#define _PAGE_RW (1UL<<1) /* writeable */
+#define _PAGE_PS (1UL<<7) /* page size bit*/
+
+#define TDX_TEST_PORT 0x33
+
+#define GDT_ENTRY(flags, base, limit) \
+ ((((base) & 0xff000000ULL) << (56-24)) | \
+ (((flags) & 0x0000f0ffULL) << 40) | \
+ (((limit) & 0x000f0000ULL) << (48-16)) | \
+ (((base) & 0x00ffffffULL) << 16) | \
+ (((limit) & 0x0000ffffULL)))
+
+struct tdx_cpuid_data {
+ struct kvm_cpuid2 cpuid;
+ struct kvm_cpuid_entry2 entries[KVM_MAX_CPUID_ENTRIES];
+};
+
+struct __packed tdx_gdtr {
+ uint16_t limit;
+ uint32_t base;
+};
+
+struct page_table {
+ uint64_t pml4[512];
+ uint64_t pdpt[512];
+ uint64_t pd[4][512];
+};
+
+void add_td_memory(struct kvm_vm *vm, void *source_page,
+ uint64_t gpa, int size);
+void finalize_td_memory(struct kvm_vm *vm);
+void initialize_td(struct kvm_vm *vm);
+void initialize_td_vcpu(struct kvm_vm *vm, uint32_t vcpuid);
+void prepare_source_image(struct kvm_vm *vm, void *guest_code,
+ size_t guest_code_size,
+ uint64_t guest_code_signature);
+
+#endif // KVM_LIB_TDX_H_
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx_lib.c b/tools/testing/selftests/kvm/lib/x86_64/tdx_lib.c
new file mode 100644
index 000000000..03f0c3af8
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx_lib.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "tdx.h"
+#include <stdlib.h>
+#include <malloc.h>
+#include "processor.h"
+
+char *tdx_cmd_str[] = {
+ "KVM_TDX_CAPABILITIES",
+ "KVM_TDX_INIT_VM",
+ "KVM_TDX_INIT_VCPU",
+ "KVM_TDX_INIT_MEM_REGION",
+ "KVM_TDX_FINALIZE_VM"
+};
+
+#define TDX_MAX_CMD_STR (ARRAY_SIZE(tdx_cmd_str))
+#define EIGHT_INT3_INSTRUCTIONS 0xCCCCCCCCCCCCCCCC
+
+static void tdx_ioctl(int fd, int ioctl_no, uint32_t metadata, void *data)
+{
+ struct kvm_tdx_cmd tdx_cmd;
+ int r;
+
+ TEST_ASSERT(ioctl_no < TDX_MAX_CMD_STR, "Unknown TDX CMD : %d\n",
+ ioctl_no);
+
+ memset(&tdx_cmd, 0x0, sizeof(tdx_cmd));
+ tdx_cmd.id = ioctl_no;
+ tdx_cmd.metadata = metadata;
+ tdx_cmd.data = (uint64_t)data;
+ r = ioctl(fd, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd);
+ TEST_ASSERT(r == 0, "%s failed: %d %d", tdx_cmd_str[ioctl_no], r,
+ errno);
+}
+
+/*
+ * Initialize a VM as a TD.
+ *
+ */
+void initialize_td(struct kvm_vm *vm)
+{
+ int ret, i;
+ struct tdx_cpuid_data cpuid_data;
+ int rc;
+
+ /* No guest VMM controlled cpuid information yet. */
+ struct kvm_tdx_init_vm init_vm;
+
+ rc = kvm_check_cap(KVM_CAP_X2APIC_API);
+ TEST_ASSERT(rc, "TDX: KVM_CAP_X2APIC_API is not supported!");
+ rc = kvm_check_cap(KVM_CAP_SPLIT_IRQCHIP);
+ TEST_ASSERT(rc, "TDX: KVM_CAP_SPLIT_IRQCHIP is not supported!");
+
+ struct kvm_enable_cap cap = {
+ .cap = KVM_CAP_X2APIC_API,
+ .args[0] = KVM_X2APIC_API_USE_32BIT_IDS |
+ KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK
+ };
+ vm_enable_cap(vm, &cap);
+ struct kvm_enable_cap cap2 = {
+ .cap = KVM_CAP_SPLIT_IRQCHIP,
+ .args[0] = 24
+ };
+ vm_enable_cap(vm, &cap2);
+
+ /* Allocate and setup memoryfor the td guest. */
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+ TDX_GUEST_PT_FIXED_ADDR,
+ 0, TDX_GUEST_MAX_NR_PAGES, 0);
+
+ memset(&init_vm, 0, sizeof(init_vm));
+ memset(&cpuid_data, 0, sizeof(cpuid_data));
+ cpuid_data.cpuid.nent = KVM_MAX_CPUID_ENTRIES;
+ ret = ioctl(vm->kvm_fd, KVM_GET_SUPPORTED_CPUID, &cpuid_data);
+ TEST_ASSERT(ret == 0, "KVM_GET_SUPPORTED_CPUID failed %d %d\n",
+ ret, errno);
+ for (i = 0; i < KVM_MAX_CPUID_ENTRIES; i++) {
+ struct kvm_cpuid_entry2 *e = &cpuid_data.entries[i];
+
+ /* Setting max VA and PA bits to 48. This will make sure that
+ * TDX module will use 4 level SEPT structures.
+ */
+ if (e->function == 0x80000008 && (e->index == 0)) {
+ e->eax = 0x3030;
+ break;
+ }
+ }
+ init_vm.max_vcpus = 1;
+ init_vm.attributes = 0;
+ init_vm.cpuid = (uint64_t)&cpuid_data;
+ tdx_ioctl(vm->fd, KVM_TDX_INIT_VM, 0, &init_vm);
+}
+
+
+void initialize_td_vcpu(struct kvm_vm *vm, uint32_t vcpuid)
+{
+ struct vcpu *vcpu = vcpu_find(vm, vcpuid);
+
+ TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);
+ tdx_ioctl(vcpu->fd, KVM_TDX_INIT_VCPU, 0, NULL);
+}
+
+void add_td_memory(struct kvm_vm *vm, void *source_pages,
+ uint64_t gpa, int size)
+{
+ struct kvm_tdx_init_mem_region mem_region = {
+ .source_addr = (uint64_t)source_pages,
+ .gpa = gpa,
+ .nr_pages = size / PAGE_SIZE,
+ };
+ uint32_t metadata = KVM_TDX_MEASURE_MEMORY_REGION;
+
+ TEST_ASSERT((mem_region.nr_pages > 0) &&
+ ((mem_region.nr_pages * PAGE_SIZE) == size),
+ "Cannot add partial pages to the guest memory.\n");
+ TEST_ASSERT(((uint64_t)source_pages & (PAGE_SIZE - 1)) == 0,
+ "Source memory buffer is not page aligned\n");
+ tdx_ioctl(vm->fd, KVM_TDX_INIT_MEM_REGION, metadata, &mem_region);
+}
+
+void finalize_td_memory(struct kvm_vm *vm)
+{
+ tdx_ioctl(vm->fd, KVM_TDX_FINALIZE_VM, 0, NULL);
+}
+
+void build_gdtr_table(void *gdtr_target, void *gdt_target)
+{
+ uint64_t gdt_table[] = {
+ GDT_ENTRY(0, 0, 0), // NULL_SEL
+ GDT_ENTRY(0xc093, 0, 0xfffff), // LINEAR_DATA32_SEL
+ GDT_ENTRY(0xc09b, 0, 0xfffff), // LINEAR_CODE32_SEL
+ GDT_ENTRY(0, 0, 0), // NULL_SEL
+ GDT_ENTRY(0, 0, 0), // NULL_SEL
+ GDT_ENTRY(0, 0, 0), // NULL_SEL
+ GDT_ENTRY(0, 0, 0), // NULL_SEL
+ GDT_ENTRY(0xa09b, 0, 0xfffff) // LINEAR_CODE64_SEL
+ };
+
+ struct tdx_gdtr gdtr;
+
+ gdtr.limit = sizeof(gdt_table) - 1;
+ gdtr.base = TDX_GUEST_GDTR_BASE;
+
+ memcpy(gdt_target, gdt_table, sizeof(gdt_table));
+ memcpy(gdtr_target, &gdtr, sizeof(gdtr));
+
+}
+
+
+/*
+ * Constructing 1:1 mapping for the lowest 4GB address space using 2MB pages
+ * which will be used by the TDX guest when paging is enabled.
+ * TODO: use virt_pg_map() functions to dynamically allocate the page tables.
+ */
+void build_page_tables(void *pt_target, uint64_t pml4_base_address)
+{
+ uint64_t i;
+ struct page_table *pt;
+
+ pt = malloc(sizeof(struct page_table));
+ TEST_ASSERT(pt != NULL, "Could not allocate memory for page tables!\n");
+ memset((void *) &(pt->pml4[0]), 0, sizeof(pt->pml4));
+ memset((void *) &(pt->pdpt[0]), 0, sizeof(pt->pdpt));
+ for (i = 0; i < 4; i++)
+ memset((void *) &(pt->pd[i][0]), 0, sizeof(pt->pd[i]));
+
+ pt->pml4[0] = (pml4_base_address + PAGE_SIZE) |
+ _PAGE_PRESENT | _PAGE_RW;
+ for (i = 0; i < 4; i++)
+ pt->pdpt[i] = (pml4_base_address + (i + 2) * PAGE_SIZE) |
+ _PAGE_PRESENT | _PAGE_RW;
+
+ uint64_t *pde = &(pt->pd[0][0]);
+
+ for (i = 0; i < sizeof(pt->pd) / sizeof(pt->pd[0][0]); i++, pde++)
+ *pde = (i << 21) | _PAGE_PRESENT | _PAGE_RW | _PAGE_PS;
+ memcpy(pt_target, pt, 6 * PAGE_SIZE);
+}
+
+static void
+__attribute__((__flatten__, section("guest_boot_section"))) guest_boot(void)
+{
+ asm volatile(" .code32\n\t;"
+ "main_32:\n\t;"
+ " cli\n\t;"
+ " movl $" __stringify(TDX_GUEST_STACK_BASE) ", %%esp\n\t;"
+ " movl $" __stringify(TDX_GUEST_GDTR_ADDR) ", %%eax\n\t;"
+ " lgdt (%%eax)\n\t;"
+ " movl $0x660, %%eax\n\t;"
+ " movl %%eax, %%cr4\n\t;"
+ " movl $" __stringify(TDX_GUEST_PT_FIXED_ADDR) ", %%eax\n\t;"
+ " movl %%eax, %%cr3\n\t;"
+ " movl $0x80000023, %%eax\n\t;"
+ " movl %%eax, %%cr0\n\t;"
+ " ljmp $" __stringify(TDX_GUEST_LINEAR_CODE64_SEL)
+ ", $" __stringify(TDX_GUEST_CODE_ENTRY) "\n\t;"
+ /*
+ * This is where the CPU will start running.
+ * Do not remove any int3 instruction below.
+ */
+ "reset_vector:\n\t;"
+ " jmp main_32\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ " int3\n\t;"
+ ".code64\n\t"
+ :::"rax");
+}
+
+extern char *__start_guest_boot_section;
+extern char *__stop_guest_boot_section;
+#define GUEST_BOOT_SIZE ((uint64_t)&__stop_guest_boot_section -\
+ (uint64_t)&__start_guest_boot_section)
+
+/*
+ * Copies the guest code to the guest image. If signature value is not 0, it
+ * will verify that the guest code ends with the signature provided. We might
+ * need to check the signature to prevent compiler to add additional instruction
+ * to the end of the guest code which might create problems in some cases ie
+ * when copying code for resetvector.
+ */
+void copy_guest_code(void *target, void *guest_function, size_t code_size,
+ uint64_t signature)
+{
+ uint64_t *end;
+
+ TEST_ASSERT((target != NULL) && (guest_function != NULL) &&
+ (code_size > 0), "Invalid inputs to copy guest code\n");
+ if (signature) {
+ while (code_size >= sizeof(signature)) {
+ end = guest_function + code_size - sizeof(signature);
+ if (*end == signature)
+ break;
+ /* Trimming the unwanted code at the end added by
+ * compiler. We need to add nop instruction to the
+ * begginning of the buffer to make sure that the guest
+ * code is aligned from the bottom and top as expected
+ * based on the original code size. This is important
+ * for reset vector which is copied to the bottom of
+ * the first 4GB memory.
+ */
+ code_size--;
+ *(unsigned char *)target = 0x90;
+ target++;
+ }
+ TEST_ASSERT(code_size >= sizeof(signature),
+ "Guest code does not end with the signature: %lx\n"
+ , signature);
+ }
+
+ memcpy(target, guest_function, code_size);
+}
+
+void prepare_source_image(struct kvm_vm *vm, void *guest_code,
+ size_t guest_code_size, uint64_t guest_code_signature)
+{
+ void *source_mem, *pt_address, *code_address, *gdtr_address,
+ *gdt_address, *guest_code_base;
+ int number_of_pages;
+
+ number_of_pages = (GUEST_BOOT_SIZE + guest_code_size) / PAGE_SIZE + 1 +
+ TDX_GUEST_NR_PT_PAGES + TDX_GUEST_STACK_NR_PAGES;
+ TEST_ASSERT(number_of_pages < TDX_GUEST_MAX_NR_PAGES,
+ "Initial image does not fit to the memory");
+
+ source_mem = memalign(PAGE_SIZE,
+ (TDX_GUEST_MAX_NR_PAGES * PAGE_SIZE));
+ TEST_ASSERT(source_mem != NULL,
+ "Could not allocate memory for guest image\n");
+
+ pt_address = source_mem;
+ gdtr_address = source_mem + (TDX_GUEST_NR_PT_PAGES * PAGE_SIZE);
+ gdt_address = gdtr_address + PAGE_SIZE;
+ code_address = source_mem + (TDX_GUEST_MAX_NR_PAGES * PAGE_SIZE) -
+ GUEST_BOOT_SIZE;
+ guest_code_base = gdt_address + (TDX_GUEST_STACK_NR_PAGES *
+ PAGE_SIZE);
+
+ build_page_tables(pt_address, TDX_GUEST_PT_FIXED_ADDR);
+ build_gdtr_table(gdtr_address, gdt_address);
+
+ /* reset vector code should end with int3 instructions.
+ * The unused bytes at the reset vector with int3 to trigger triple
+ * fault shutdown if the guest manages to get into the unused code.
+ * Using the last 8 int3 instruction as a signature to find the function
+ * end offset for guest boot code that includes the instructions for
+ * reset vector.
+ * TODO: Using signature to find the exact size is a little strange but
+ * compiler might add additional bytes to the end of the function which
+ * makes it hard to calculate the offset addresses correctly.
+ * Alternatively, we can construct the jmp instruction for the reset
+ * vector manually to prevent any offset mismatch when copying the
+ * compiler generated code.
+ */
+ copy_guest_code(code_address, guest_boot, GUEST_BOOT_SIZE,
+ EIGHT_INT3_INSTRUCTIONS);
+ if (guest_code)
+ copy_guest_code(guest_code_base, guest_code, guest_code_size,
+ guest_code_signature);
+
+ add_td_memory(vm, source_mem, TDX_GUEST_PT_FIXED_ADDR,
+ (TDX_GUEST_MAX_NR_PAGES * PAGE_SIZE));
+ free(source_mem);
+}
--
2.32.0.432.gabb21c7263-goog
On Mon, Jul 26, 2021 at 11:37:56AM -0700, Erdem Aktas wrote:
> Adding a test to verify TDX lifecycle by creating a TD and running a
> dummy TDVMCALL<INSTRUCTION.IO> inside it.
>
> Signed-off-by: Erdem Aktas <[email protected]>
> Reviewed-by: Sean Christopherson <[email protected]>
> Reviewed-by: Peter Gonda <[email protected]>
> Reviewed-by: Marc Orr <[email protected]>
> Reviewed-by: Sagi Shahar <[email protected]>
> ---
> tools/testing/selftests/kvm/Makefile | 1 +
> tools/testing/selftests/kvm/lib/x86_64/tdx.h | 131 ++++++++++++++++++
> .../selftests/kvm/x86_64/tdx_vm_tests.c | 102 ++++++++++++++
> 3 files changed, 234 insertions(+)
> create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
>
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index d84c09b5e..259be634c 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -72,6 +72,7 @@ TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus
> TEST_GEN_PROGS_x86_64 += memslot_modification_stress_test
> TEST_GEN_PROGS_x86_64 += set_memory_region_test
> TEST_GEN_PROGS_x86_64 += steal_time
> TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
> +TEST_GEN_PROGS_x86_64 += x86_64/tdx_vm_tests
>
> TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
> TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx.h b/tools/testing/selftests/kvm/lib/x86_64/tdx.h
> index 6e3e8384e..395be3c81 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/tdx.h
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx.h
> @@ -86,4 +86,135 @@ void prepare_source_image(struct kvm_vm *vm, void *guest_code,
> size_t guest_code_size,
> uint64_t guest_code_signature);
>
> +/*
> + * Generic TDCALL function that can be used to communicate with TDX module or
> + * VMM.
> + * Input operands: rax, rbx, rcx, rdx, r8-r15, rbp, rsi, rdi
> + * Output operands: rax, r8-r15, rbx, rdx, rdi, rsi
> + * rcx is actually a bitmap to tell TDX module which register values will be
> + * exposed to the VMM.
> + * XMM0-XMM15 registers can be used as input operands but the current
> + * implementation does not support it yet.
> + */
> +static inline void tdcall(struct kvm_regs *regs)
> +{
> + asm volatile (
> + "mov %13, %%rax;\n\t"
> + "mov %14, %%rbx;\n\t"
> + "mov %15, %%rcx;\n\t"
> + "mov %16, %%rdx;\n\t"
> + "mov %17, %%r8;\n\t"
> + "mov %18, %%r9;\n\t"
> + "mov %19, %%r10;\n\t"
> + "mov %20, %%r11;\n\t"
> + "mov %21, %%r12;\n\t"
> + "mov %22, %%r13;\n\t"
> + "mov %23, %%r14;\n\t"
> + "mov %24, %%r15;\n\t"
> + "mov %25, %%rbp;\n\t"
> + "mov %26, %%rsi;\n\t"
> + "mov %27, %%rdi;\n\t"
> + ".byte 0x66, 0x0F, 0x01, 0xCC;\n\t"
> + "mov %%rax, %0;\n\t"
> + "mov %%rbx, %1;\n\t"
> + "mov %%rdx, %2;\n\t"
> + "mov %%r8, %3;\n\t"
> + "mov %%r9, %4;\n\t"
> + "mov %%r10, %5;\n\t"
> + "mov %%r11, %6;\n\t"
> + "mov %%r12, %7;\n\t"
> + "mov %%r13, %8;\n\t"
> + "mov %%r14, %9;\n\t"
> + "mov %%r15, %10;\n\t"
> + "mov %%rsi, %11;\n\t"
> + "mov %%rdi, %12;\n\t"
> + : "=m" (regs->rax), "=m" (regs->rbx), "=m" (regs->rdx),
> + "=m" (regs->r8), "=m" (regs->r9), "=m" (regs->r10),
> + "=m" (regs->r11), "=m" (regs->r12), "=m" (regs->r13),
> + "=m" (regs->r14), "=m" (regs->r15), "=m" (regs->rsi),
> + "=m" (regs->rdi)
> + : "m" (regs->rax), "m" (regs->rbx), "m" (regs->rcx),
> + "m" (regs->rdx), "m" (regs->r8), "m" (regs->r9),
> + "m" (regs->r10), "m" (regs->r11), "m" (regs->r12),
> + "m" (regs->r13), "m" (regs->r14), "m" (regs->r15),
> + "m" (regs->rbp), "m" (regs->rsi), "m" (regs->rdi)
> + : "rax", "rbx", "rcx", "rdx", "r8", "r9", "r10", "r11",
> + "r12", "r13", "r14", "r15", "rbp", "rsi", "rdi");
> +}
> +
> +
> +/*
> + * Do a TDVMCALL IO request
> + *
> + * Input Args:
> + * port - IO port to do read/write
> + * size - Number of bytes to read/write. 1=1byte, 2=2bytes, 4=4bytes.
> + * write - 1=IO write 0=IO read
> + * data - pointer for the data to write
> + *
> + * Output Args:
> + * data - pointer for data to be read
> + *
> + * Return:
> + * On success, return 0. For Invalid-IO-Port error, returns -1.
> + *
> + * Does an IO operation using the following tdvmcall interface.
> + *
> + * TDG.VP.VMCALL<Instruction.IO>-Input Operands
> + * R11 30 for IO
> + *
> + * R12 Size of access. 1=1byte, 2=2bytes, 4=4bytes.
> + * R13 Direction. 0=Read, 1=Write.
> + * R14 Port number
> + * R15 Data to write, if R13 is 1.
> + *
> + * TDG.VP.VMCALL<Instruction.IO>-Output Operands
> + * R10 TDG.VP.VMCALL-return code.
> + * R11 Data to read, if R13 is 0.
> + *
> + * TDG.VP.VMCALL<Instruction.IO>-Status Codes
> + * Error Code Value Description
> + * TDG.VP.VMCALL_SUCCESS 0x0 TDG.VP.VMCALL is successful
> + * TDG.VP.VMCALL_INVALID_OPERAND 0x80000000 00000000 Invalid-IO-Port access
> + */
> +static inline int tdvmcall_io(uint64_t port, uint64_t size,
> + uint64_t write, uint64_t *data)
> +{
> + struct kvm_regs regs;
> +
> + memset(®s, 0, sizeof(regs));
> + regs.r11 = 30;
> + regs.r12 = size;
> + regs.r13 = write;
> + regs.r14 = port;
> + if (write)
> + regs.r15 = *data;
> + /* TODO: update the bitmap register with only the relavent registers */
> + regs.rcx = 0xFC00;
> + tdcall(®s);
> + if (!write)
> + *data = regs.r11;
> + return regs.r10;
> +}
> +
> +
> +#define TDX_FUNCTION_SIZE(name) ((uint64_t)&__stop_sec_ ## name -\
> + (uint64_t)&__start_sec_ ## name) \
> +
> +#define TDX_GUEST_FUNCTION__(name, section_name) \
> +extern char *__start_sec_ ## name ; \
> +extern char *__stop_sec_ ## name ; \
> +static void \
> +__attribute__((__flatten__, section(section_name))) name(void *arg)
> +
> +
> +#define STRINGIFY2(x) #x
> +#define STRINGIFY(x) STRINGIFY2(x)
> +#define CONCAT2(a, b) a##b
> +#define CONCAT(a, b) CONCAT2(a, b)
> +
> +
> +#define TDX_GUEST_FUNCTION(name) \
> +TDX_GUEST_FUNCTION__(name, STRINGIFY(CONCAT(sec_, name)))
> +
> #endif // KVM_LIB_TDX_H_
> diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> new file mode 100644
> index 000000000..da7ea67b1
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> @@ -0,0 +1,102 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <fcntl.h>
> +#include <limits.h>
> +#include <kvm_util.h>
> +#include "../lib/kvm_util_internal.h"
> +#include "../lib/x86_64/tdx.h"
> +#include <linux/kvm.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <sys/ioctl.h>
> +#include <sys/types.h>
> +#include <test_util.h>
> +#include <unistd.h>
> +#include <processor.h>
> +#include <time.h>
> +#include <sys/mman.h>
> +#include<sys/wait.h>
> +
> +/*
> + * There might be multiple tests we are running and if one test fails, it will
> + * prevent the subsequent tests to run due to how tests are failing with
> + * TEST_ASSERT function. The run_in_new_process function will run a test in a
> + * new process context and wait for it to finish or fail to prevent TEST_ASSERT
> + * to kill the main testing process.
> + */
> +void run_in_new_process(void (*func)(void))
> +{
> + if (fork() == 0) {
> + func();
> + exit(0);
> + }
> + wait(NULL);
> +}
> +
> +/*
> + * Verify that the TDX is supported by the KVM.
> + */
> +bool is_tdx_enabled(void)
> +{
> + return !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_TDX_VM));
> +}
> +
> +/*
> + * Do a dummy io exit to verify that the TD has been initialized correctly and
> + * guest can run some code inside.
> + */
> +TDX_GUEST_FUNCTION(guest_dummy_exit)
> +{
> + uint64_t data;
> +
> + data = 0xAB;
> + tdvmcall_io(TDX_TEST_PORT, 1, 1, &data);
> +}
> +
> +/*
> + * TD lifecycle test will create a TD which runs a dumy IO exit to verify that
> + * the guest TD has been created correctly.
> + */
> +void verify_td_lifecycle(void)
> +{
> + struct kvm_vm *vm;
> + struct kvm_run *run;
> +
> + printf("Verifying TD lifecycle:\n");
> + /* Create a TD VM with no memory.*/
> + vm = __vm_create(VM_MODE_DEFAULT, 0, O_RDWR, KVM_X86_TDX_VM);
> +
> + /* Allocate TD guest memory and initialize the TD.*/
> + initialize_td(vm);
> +
> + /* Initialize the TD vcpu and copy the test code to the guest memory.*/
> + vm_vcpu_add_tdx(vm, 0);
> +
> + /* Setup and initialize VM memory */
> + prepare_source_image(vm, guest_dummy_exit,
> + TDX_FUNCTION_SIZE(guest_dummy_exit), 0);
> + finalize_td_memory(vm);
> +
> + run = vcpu_state(vm, 0);
> + vcpu_run(vm, 0);
> + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
> + "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
> + run->exit_reason,
> + exit_reason_str(run->exit_reason));
> +
> + kvm_vm_free(vm);
> + printf("\t ... PASSED\n");
> +}
> +int main(int argc, char **argv)
> +{
> + if (!is_tdx_enabled()) {
> + printf("TDX is not supported by the KVM\n"
> + "Skipping the TDX tests.\n");
Use print_skip() to emit the standard "skipping test" message.
> + return 0;
Exit with KSFT_SKIP so that test runners know that this test was skipped
(rather than running and passing).
> + }
> +
> + run_in_new_process(&verify_td_lifecycle);
> +
> + return 0;
> +}
> --
> 2.32.0.432.gabb21c7263-goog
>
> -----Original Message-----
> From: Erdem Aktas <[email protected]>
> Sent: Tuesday, July 27, 2021 2:38 AM
> To: [email protected]
> Cc: [email protected]; Paolo Bonzini <[email protected]>; Shuah
> Khan <[email protected]>; Andrew Jones <[email protected]>; Ben
> Gardon <[email protected]>; Peter Xu <[email protected]>; Sean
> Christopherson <[email protected]>; Christian Borntraeger
> <[email protected]>; Eric Auger <[email protected]>;
> Emanuele Giuseppe Esposito <[email protected]>; Ricardo Koller
> <[email protected]>; Duan, Zhenzhong <[email protected]>;
> Aaron Lewis <[email protected]>; Jim Mattson
> <[email protected]>; Oliver Upton <[email protected]>; Vitaly
> Kuznetsov <[email protected]>; Peter Shier <[email protected]>; Axel
> Rasmussen <[email protected]>; Yanan Wang
> <[email protected]>; Maciej S. Szmigiero
> <[email protected]>; David Matlack <[email protected]>;
> Like Xu <[email protected]>; open list <[email protected]>;
> open list:KERNEL VIRTUAL MACHINE (KVM) <[email protected]>
> Subject: [RFC PATCH 0/4] TDX KVM selftests
>
> TDX stands for Trust Domain Extensions which isolates VMs from the virtual-
> machine manager (VMM)/hypervisor and any other software on the
> platform.
>
> Intel has recently submitted a set of RFC patches for KVM support for TDX
> and more information can be found on the latest TDX Support
> Patches: https://lkml.org/lkml/2021/7/2/558
>
> Due to the nature of the confidential computing environment that TDX
> provides, it is very difficult to verify/test the KVM support. TDX requires UEFI
> and the guest kernel to be enlightened which are all under development.
>
> We are working on a set of selftests to close this gap and be able to verify the
> KVM functionality to support TDX lifecycle and GHCI [1] interface.
>
> We are looking for any feedback on:
> - Patch series itself
> - Any suggestion on how we should approach testing TDX functionality.
> Does selftests seems reasonable or should we switch to using KVM unit tests.
> I would be happy to get some perspective on how KVM unit tests can help us
> more.
> - Any test case or scenario that we should add.
> - Anything else I have not thought of yet.
>
> Current patch series provide the following capabilities:
>
> - Provide helper functions to create a TD (Trusted Domain) using the KVM
> ioctls
> - Provide helper functions to create a guest image that can include any
> testing code
> - Provide helper functions and wrapper functions to write testing code
> using GHCI interface
> - Add a test case that verifies TDX life cycle
> - Add a test case that verifies TDX GHCI port IO
>
> TODOs:
> - Use existing function to create page tables dynamically
> (ie __virt_pg_map())
> - Remove arbitrary defined magic numbers for data structure offsets
> - Add TDVMCALL for error reporting
> - Add additional test cases as some listed below
> - Add #VE handlers to help testing more complicated test cases
>
> Other test cases that we are planning to add:
> (with credit to [email protected])
>
> VM call interface Input Output Result
> GetTdVmCallInfo R12=0 None VMCALL_SUCCESS
> MapGPA Map private page (GPA.S=0)
> VMCALL_SUCCESS
> MapGPA Map shared page (GPA.S=1)
> VMCALL_SUCCESS
> MapGPA Map already private page as private
> VMCALL_INVALID_OPERAND
> MapGPA Map already shared page as shared
> VMCALL_INVALID_OPERAND
> GetQuote
> ReportFatalError
> SetupEventNotifyInterrupt Valid interrupt value (32:255)
> VMCALL_SUCCESS
> SetupEventNotifyInterrupt Invalid value (>255)
> VMCALL_INVALID_OPERAND
> Instruction.CPUID R12(EAX)=1, R13(ECX)=0 EBX[8:15]=0x8
> EBX[16:23]=X
> EBX[24:31]=vcpu_id
> ECX[0]=1
> ECX[12]=Y
> Instruction.CPUID R12(EAX)=1, R13(ECX)=4
> VMCALL_INVALID_OPERAND
> VE.RequestMMIO
> Instruction.HLT VMCALL_SUCCESS
> Instruction.IO Read/Write 1/2/4 bytes VMCALL_SUCCESS
> Instruction.IO Read/Write 3 bytes
> VMCALL_INVALID_OPERAND
> Instruction.RDMSR Accessible register R11=msr_value
> VMCALL_SUCCESS
> Inaccessible register
> VMCALL_INVALID_OPERAND
> Instruction.RDMSR Accessible register VMCALL_SUCCESS
> Inaccessible register
> VMCALL_INVALID_OPERAND
> INSTRUCTION.PCONFIG
>
> [1] Intel TDX Guest-Hypervisor Communication Interface
>
> https://software.intel.com/content/dam/develop/external/us/en/document
> s/intel-tdx-guest-hypervisor-communication-interface.pdf
>
>
> Erdem Aktas (4):
> KVM: selftests: Add support for creating non-default type VMs
> KVM: selftest: Add helper functions to create TDX VMs
In tools/testing/selftests/kvm/Makefile, '/lib/x86_64/tdx_lib.c' should be changed to 'lib/x86_64/tdx_lib.c'
After that, build and test passes.
# ./tdx_vm_tests
Verifying TD lifecycle:
Verifying TD IO Exit:
... IO WRITE: OK
... IO READ: OK
... IO verify read/write values: OK
Tested-by: Zhenzhong Duan <[email protected]>
Regards
Zhenzhong