A common aspect of booting SEV guests is checking related CPUID/MSR bits and accessing shared/private memory. Add a basic test to cover this.
This test will be expanded to cover basic boot of SEV-ES and SEV-SNP in subsequent patches.
Signed-off-by: Michael Roth michael.roth@amd.com --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/x86_64/sev_all_boot_test.c | 252 ++++++++++++++++++ 3 files changed, 254 insertions(+) create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 0709af0144c8..824f100bec2a 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -38,6 +38,7 @@ /x86_64/xen_vmcall_test /x86_64/xss_msr_test /x86_64/vmx_pmu_msrs_test +/x86_64/sev_all_boot_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 c7a5e1c69e0c..aa8901bdbd22 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -72,6 +72,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/tsc_msrs_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_pmu_msrs_test TEST_GEN_PROGS_x86_64 += x86_64/xen_shinfo_test TEST_GEN_PROGS_x86_64 += x86_64/xen_vmcall_test +TEST_GEN_PROGS_x86_64 += x86_64/sev_all_boot_test TEST_GEN_PROGS_x86_64 += access_tracking_perf_test TEST_GEN_PROGS_x86_64 += demand_paging_test TEST_GEN_PROGS_x86_64 += dirty_log_test diff --git a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c new file mode 100644 index 000000000000..8df7143ac17d --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c @@ -0,0 +1,252 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Basic SEV boot tests. + * + * Copyright (C) 2021 Advanced Micro Devices + */ +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> + +#include "test_util.h" + +#include "kvm_util.h" +#include "processor.h" +#include "svm_util.h" +#include "linux/psp-sev.h" +#include "sev.h" + +#define VCPU_ID 2 +#define PAGE_SIZE 4096 +#define PAGE_STRIDE 32 + +#define SHARED_PAGES 8192 +#define SHARED_VADDR_MIN 0x1000000 + +#define PRIVATE_PAGES 2048 +#define PRIVATE_VADDR_MIN (SHARED_VADDR_MIN + SHARED_PAGES * PAGE_SIZE) + +#define TOTAL_PAGES (512 + SHARED_PAGES + PRIVATE_PAGES) + +static void fill_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val) +{ + int i, j; + + for (i = 0; i < pages; i++) + for (j = 0; j < PAGE_SIZE; j += stride) + buf[i * PAGE_SIZE + j] = val; +} + +static bool check_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val) +{ + int i, j; + + for (i = 0; i < pages; i++) + for (j = 0; j < PAGE_SIZE; j += stride) + if (buf[i * PAGE_SIZE + j] != val) + return false; + + return true; +} + +static void guest_test_start(struct sev_sync_data *sync) +{ + /* Initial guest check-in. */ + sev_guest_sync(sync, 1, 0); +} + +static void check_test_start(struct kvm_vm *vm, struct sev_sync_data *sync) +{ + struct kvm_run *run; + + run = vcpu_state(vm, VCPU_ID); + vcpu_run(vm, VCPU_ID); + + /* Initial guest check-in. */ + sev_check_guest_sync(run, sync, 1); +} + +static void +guest_test_common(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf) +{ + bool success; + + /* Initial check-in for common. */ + sev_guest_sync(sync, 100, 0); + + /* Ensure initial shared pages are intact. */ + success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41); + SEV_GUEST_ASSERT(sync, 103, success); + + /* Ensure initial private pages are intact/encrypted. */ + success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42); + SEV_GUEST_ASSERT(sync, 104, success); + + /* Ensure host userspace can't read newly-written encrypted data. */ + fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43); + + sev_guest_sync(sync, 200, 0); + + /* Ensure guest can read newly-written shared data from host. */ + success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44); + SEV_GUEST_ASSERT(sync, 201, success); + + /* Ensure host can read newly-written shared data from guest. */ + fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45); + + sev_guest_sync(sync, 300, 0); +} + +static void +check_test_common(struct kvm_vm *vm, struct sev_sync_data *sync, + uint8_t *shared_buf, uint8_t *private_buf) +{ + struct kvm_run *run = vcpu_state(vm, VCPU_ID); + bool success; + + /* Initial guest check-in. */ + vcpu_run(vm, VCPU_ID); + sev_check_guest_sync(run, sync, 100); + + /* Ensure initial private pages are intact/encrypted. */ + success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42); + TEST_ASSERT(!success, "Initial guest memory not encrypted!"); + + vcpu_run(vm, VCPU_ID); + sev_check_guest_sync(run, sync, 200); + + /* Ensure host userspace can't read newly-written encrypted data. */ + success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43); + TEST_ASSERT(!success, "Modified guest memory not encrypted!"); + + /* Ensure guest can read newly-written shared data from host. */ + fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44); + + vcpu_run(vm, VCPU_ID); + sev_check_guest_sync(run, sync, 300); + + /* Ensure host can read newly-written shared data from guest. */ + success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45); + TEST_ASSERT(success, "Host can't read shared guest memory!"); +} + +static void +guest_test_done(struct sev_sync_data *sync) +{ + sev_guest_done(sync, 10000, 0); +} + +static void +check_test_done(struct kvm_vm *vm, struct sev_sync_data *sync) +{ + struct kvm_run *run = vcpu_state(vm, VCPU_ID); + + vcpu_run(vm, VCPU_ID); + sev_check_guest_done(run, sync, 10000); +} + +static void __attribute__((__flatten__)) +guest_sev_code(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf) +{ + uint32_t eax, ebx, ecx, edx; + uint64_t sev_status; + + guest_test_start(sync); + + /* Check SEV CPUID bit. */ + eax = 0x8000001f; + ecx = 0; + cpuid(&eax, &ebx, &ecx, &edx); + SEV_GUEST_ASSERT(sync, 2, eax & (1 << 1)); + + /* Check SEV MSR bit. */ + sev_status = rdmsr(MSR_AMD64_SEV); + SEV_GUEST_ASSERT(sync, 3, (sev_status & 0x1) == 1); + + guest_test_common(sync, shared_buf, private_buf); + + guest_test_done(sync); +} + +static void +setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr, + vm_vaddr_t *shared_vaddr, vm_vaddr_t *private_vaddr) +{ + struct kvm_vm *vm = sev_get_vm(sev); + uint8_t *shared_buf, *private_buf; + + /* Set up VCPU and initial guest kernel. */ + vm_vcpu_add_default(vm, VCPU_ID, guest_code); + kvm_vm_elf_load(vm, program_invocation_name); + + /* Set up shared sync buffer. */ + *sync_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0); + + /* Set up buffer for reserved shared memory. */ + *shared_vaddr = vm_vaddr_alloc_shared(vm, SHARED_PAGES * PAGE_SIZE, + SHARED_VADDR_MIN); + shared_buf = addr_gva2hva(vm, *shared_vaddr); + fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41); + + /* Set up buffer for reserved private memory. */ + *private_vaddr = vm_vaddr_alloc(vm, PRIVATE_PAGES * PAGE_SIZE, + PRIVATE_VADDR_MIN); + private_buf = addr_gva2hva(vm, *private_vaddr); + fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42); +} + +static void test_sev(void *guest_code, uint64_t policy) +{ + vm_vaddr_t sync_vaddr, shared_vaddr, private_vaddr; + uint8_t *shared_buf, *private_buf; + struct sev_sync_data *sync; + uint8_t measurement[512]; + struct sev_vm *sev; + struct kvm_vm *vm; + int i; + + sev = sev_vm_create(policy, TOTAL_PAGES); + if (!sev) + return; + vm = sev_get_vm(sev); + + setup_test_common(sev, guest_code, &sync_vaddr, &shared_vaddr, &private_vaddr); + + /* Set up guest params. */ + vcpu_args_set(vm, VCPU_ID, 4, sync_vaddr, shared_vaddr, private_vaddr); + + sync = addr_gva2hva(vm, sync_vaddr); + shared_buf = addr_gva2hva(vm, shared_vaddr); + private_buf = addr_gva2hva(vm, private_vaddr); + + /* Allocations/setup done. Encrypt initial guest payload. */ + sev_vm_launch(sev); + + /* Dump the initial measurement. A test to actually verify it would be nice. */ + sev_vm_measure(sev, measurement); + pr_info("guest measurement: "); + for (i = 0; i < 32; ++i) + pr_info("%02x", measurement[i]); + pr_info("\n"); + + sev_vm_launch_finish(sev); + + /* Guest is ready to run. Do the tests. */ + check_test_start(vm, sync); + check_test_common(vm, sync, shared_buf, private_buf); + check_test_done(vm, sync); + + sev_vm_free(sev); +} + +int main(int argc, char *argv[]) +{ + /* SEV tests */ + test_sev(guest_sev_code, SEV_POLICY_NO_DBG); + test_sev(guest_sev_code, 0); + + return 0; +}