From: Ryan Afranji afranji@google.com
Adds a test that sets up shared memory between the host and guest.
Signed-off-by: Ryan Afranji afranji@google.com Signed-off-by: Sagi Shahar sagis@google.com Signed-off-by: Ackerley Tng ackerleytng@google.com --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/x86_64/tdx/tdx.h | 2 + .../kvm/include/x86_64/tdx/tdx_util.h | 3 + .../selftests/kvm/lib/x86_64/tdx/tdx.c | 16 ++ .../selftests/kvm/lib/x86_64/tdx/tdx_util.c | 30 ++++ .../kvm/x86_64/tdx_shared_mem_test.c | 137 ++++++++++++++++++ 7 files changed, 190 insertions(+) create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_shared_mem_test.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 370d6430b32b4..e1663b0f809b4 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -66,6 +66,7 @@ /x86_64/vmx_pmu_caps_test /x86_64/triple_fault_event_test /x86_64/tdx_vm_tests +/x86_64/tdx_shared_mem_test /access_tracking_perf_test /demand_paging_test /dirty_log_test diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 9f289322a4933..27e9148212fa5 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -152,6 +152,7 @@ TEST_GEN_PROGS_x86_64 += steal_time TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test TEST_GEN_PROGS_x86_64 += system_counter_offset_test TEST_GEN_PROGS_x86_64 += x86_64/tdx_vm_tests +TEST_GEN_PROGS_x86_64 += x86_64/tdx_shared_mem_test
# Compiled outputs used by test targets TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h index ffab2c3ca312b..857a297e51ac6 100644 --- a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h +++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h @@ -7,6 +7,7 @@ #define TDG_VP_INFO 1
#define TDG_VP_VMCALL_GET_TD_VM_CALL_INFO 0x10000 +#define TDG_VP_VMCALL_MAP_GPA 0x10001 #define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
#define TDG_VP_VMCALL_INSTRUCTION_CPUID 10 @@ -36,5 +37,6 @@ uint64_t tdg_vp_vmcall_instruction_cpuid(uint32_t eax, uint32_t ecx, uint64_t tdg_vp_info(uint64_t *rcx, uint64_t *rdx, uint64_t *r8, uint64_t *r9, uint64_t *r10, uint64_t *r11); +uint64_t tdg_vp_vmcall_map_gpa(uint64_t address, uint64_t size, uint64_t *data_out);
#endif // SELFTEST_TDX_TDX_H diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h index 274b245f200bf..58374453b4b7e 100644 --- a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h +++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h @@ -13,4 +13,7 @@ void td_initialize(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type, uint64_t attributes); void td_finalize(struct kvm_vm *vm);
+void handle_memory_conversion(struct kvm_vm *vm, uint64_t gpa, uint64_t size, + bool shared_to_private); + #endif // SELFTESTS_TDX_KVM_UTIL_H diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c index a280136634d3b..e0a39f29a0662 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c @@ -189,3 +189,19 @@ uint64_t tdg_vp_info(uint64_t *rcx, uint64_t *rdx,
return ret; } + +uint64_t tdg_vp_vmcall_map_gpa(uint64_t address, uint64_t size, uint64_t *data_out) +{ + uint64_t ret; + struct tdx_hypercall_args args = { + .r11 = TDG_VP_VMCALL_MAP_GPA, + .r12 = address, + .r13 = size + }; + + ret = __tdx_hypercall(&args, TDX_HCALL_HAS_OUTPUT); + + if (data_out) + *data_out = args.r11; + return ret; +} diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c index 2e9679d24a843..4d6615b97770a 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c @@ -505,3 +505,33 @@ void td_finalize(struct kvm_vm *vm)
tdx_td_finalizemr(vm); } + +/** + * Handle conversion of memory with @size beginning @gpa for @vm. Set + * @shared_to_private to true for shared to private conversions and false + * otherwise. + * + * Since this is just for selftests, we will just keep both pieces of backing + * memory allocated and not deallocate/allocate memory; we'll just do the + * minimum of calling KVM_MEMORY_ENCRYPT_REG_REGION and + * KVM_MEMORY_ENCRYPT_UNREG_REGION. + */ +void handle_memory_conversion(struct kvm_vm *vm, uint64_t gpa, uint64_t size, + bool shared_to_private) +{ + struct kvm_enc_region range; + char *ioctl_string = shared_to_private + ? "KVM_MEMORY_ENCRYPT_REG_REGION" + : "KVM_MEMORY_ENCRYPT_UNREG_REGION"; + + range.addr = gpa; + range.size = size; + + printf("\t ... calling %s ioctl with gpa=%#lx, size=%#lx\n", + ioctl_string, gpa, size); + + if (shared_to_private) + vm_ioctl(vm, KVM_MEMORY_ENCRYPT_REG_REGION, &range); + else + vm_ioctl(vm, KVM_MEMORY_ENCRYPT_UNREG_REGION, &range); +} diff --git a/tools/testing/selftests/kvm/x86_64/tdx_shared_mem_test.c b/tools/testing/selftests/kvm/x86_64/tdx_shared_mem_test.c new file mode 100644 index 0000000000000..eb4cf64ae83a8 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/tdx_shared_mem_test.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/kvm.h> +#include <stdint.h> + +#include "kvm_util_base.h" +#include "processor.h" +#include "tdx/tdcall.h" +#include "tdx/tdx.h" +#include "tdx/tdx_util.h" +#include "tdx/test_util.h" +#include "test_util.h" + +#define TDX_SHARED_MEM_TEST_PRIVATE_GVA (0x80000000) +#define TDX_SHARED_MEM_TEST_VADDR_SHARED_MASK BIT_ULL(30) +#define TDX_SHARED_MEM_TEST_SHARED_GVA \ + (TDX_SHARED_MEM_TEST_PRIVATE_GVA | \ + TDX_SHARED_MEM_TEST_VADDR_SHARED_MASK) + +#define TDX_SHARED_MEM_TEST_GUEST_WRITE_VALUE (0xcafecafe) +#define TDX_SHARED_MEM_TEST_HOST_WRITE_VALUE (0xabcdabcd) + +#define TDX_SHARED_MEM_TEST_INFO_PORT 0x87 + +/* + * Shared variables between guest and host + */ +static uint64_t test_mem_private_gpa; +static uint64_t test_mem_shared_gpa; + +void guest_shared_mem(void) +{ + uint32_t *test_mem_shared_gva = + (uint32_t *)TDX_SHARED_MEM_TEST_SHARED_GVA; + + uint64_t placeholder; + uint64_t ret; + + /* Map gpa as shared */ + ret = tdg_vp_vmcall_map_gpa(test_mem_shared_gpa, PAGE_SIZE, + &placeholder); + if (ret) + tdx_test_fatal_with_data(ret, __LINE__); + + *test_mem_shared_gva = TDX_SHARED_MEM_TEST_GUEST_WRITE_VALUE; + + /* Exit so host can read shared value */ + ret = tdg_vp_vmcall_instruction_io(TDX_SHARED_MEM_TEST_INFO_PORT, 4, + TDG_VP_VMCALL_INSTRUCTION_IO_WRITE, + &placeholder); + if (ret) + tdx_test_fatal_with_data(ret, __LINE__); + + /* Read value written by host and send it back out for verification */ + ret = tdg_vp_vmcall_instruction_io(TDX_SHARED_MEM_TEST_INFO_PORT, 4, + TDG_VP_VMCALL_INSTRUCTION_IO_WRITE, + (uint64_t *)test_mem_shared_gva); + if (ret) + tdx_test_fatal_with_data(ret, __LINE__); +} + +int verify_shared_mem(void) +{ + struct kvm_vm *vm; + struct kvm_vcpu *vcpu; + + vm_vaddr_t test_mem_private_gva; + uint32_t *test_mem_hva; + + vm = td_create(); + td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0); + vcpu = td_vcpu_add(vm, 0, guest_shared_mem); + + /* + * Set up shared memory page for testing by first allocating as private + * and then mapping the same GPA again as shared. This way, the TD does + * not have to remap its page tables at runtime. + */ + test_mem_private_gva = vm_vaddr_alloc(vm, vm->page_size, + TDX_SHARED_MEM_TEST_PRIVATE_GVA); + ASSERT_EQ(test_mem_private_gva, TDX_SHARED_MEM_TEST_PRIVATE_GVA); + + test_mem_hva = addr_gva2hva(vm, test_mem_private_gva); + TEST_ASSERT(test_mem_hva != NULL, + "Guest address not found in guest memory regions\n"); + + test_mem_private_gpa = addr_gva2gpa(vm, test_mem_private_gva); + virt_pg_map_shared(vm, TDX_SHARED_MEM_TEST_SHARED_GVA, + test_mem_private_gpa); + + test_mem_shared_gpa = test_mem_private_gpa | BIT_ULL(vm->pa_bits - 1); + sync_global_to_guest(vm, test_mem_private_gpa); + sync_global_to_guest(vm, test_mem_shared_gpa); + + td_finalize(vm); + + printf("Verifying shared memory accesses for TDX\n"); + + /* Begin guest execution; guest writes to shared memory. */ + printf("\t ... Starting guest execution\n"); + + /* Handle map gpa as shared */ + /* TODO: MapGPA should exit to the host VMM, but now it doesn't */ + // vcpu_run(vcpu); + // ASSERT_EQ(vcpu->run->exit_reason, KVM_EXIT_MEMORY_FAULT); + // handle_memory_conversion(vm, vcpu->run->memory.gpa, vcpu->run->memory.size, + // vcpu->run->memory.flags == KVM_MEMORY_EXIT_FLAG_PRIVATE); + + vcpu_run(vcpu); + TDX_TEST_ASSERT_IO(vcpu, TDX_SHARED_MEM_TEST_INFO_PORT, 4, + TDG_VP_VMCALL_INSTRUCTION_IO_WRITE); + ASSERT_EQ(*test_mem_hva, TDX_SHARED_MEM_TEST_GUEST_WRITE_VALUE); + + *test_mem_hva = TDX_SHARED_MEM_TEST_HOST_WRITE_VALUE; + vcpu_run(vcpu); + TDX_TEST_ASSERT_IO(vcpu, TDX_SHARED_MEM_TEST_INFO_PORT, 4, + TDG_VP_VMCALL_INSTRUCTION_IO_WRITE); + ASSERT_EQ(*(uint32_t *)((void *)vcpu->run + vcpu->run->io.data_offset), + TDX_SHARED_MEM_TEST_HOST_WRITE_VALUE); + + printf("\t ... PASSED\n"); + + kvm_vm_free(vm); + + return 0; +} + +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; + } + + return verify_shared_mem(); +}