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 erdemaktas@google.com Reviewed-by: Sean Christopherson seanjc@google.com Reviewed-by: Peter Gonda pgonda@google.com Reviewed-by: Marc Orr marcorr@google.com Reviewed-by: Sagi Shahar sagis@google.com --- 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; +}