On Thu, Dec 16, 2021, Michael Roth wrote:
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 | 255 ++++++++++++++++++ 3 files changed, 257 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 4a801cba9c62..cc73de938a2a 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -43,6 +43,7 @@ /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 ccc382a827f1..6f250e190fde 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -81,6 +81,7 @@ 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/vmx_pi_mmio_test TEST_GEN_PROGS_x86_64 += x86_64/sev_migrate_tests +TEST_GEN_PROGS_x86_64 += x86_64/sev_all_boot_test TEST_GEN_PROGS_x86_64 += demand_paging_test TEST_GEN_PROGS_x86_64 += dirty_log_test TEST_GEN_PROGS_x86_64 += dirty_log_perf_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..329a740a7cb2 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c @@ -0,0 +1,255 @@ +// 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 ucall *uc) +{
- /* Initial guest check-in. */
- GUEST_SHARED_SYNC(uc, 1);
+}
+static void test_start(struct kvm_vm *vm, struct ucall *uc) +{
- vcpu_run(vm, VCPU_ID);
- /* Initial guest check-in. */
- CHECK_SHARED_SYNC(vm, VCPU_ID, uc, 1);
+}
+static void +guest_test_common(struct ucall *uc, uint8_t *shared_buf, uint8_t *private_buf) +{
- bool success;
- /* Initial check-in for common. */
- GUEST_SHARED_SYNC(uc, 100);
Probably, you want to use macros to represent those states which should make it more clear. Otherwise, it is quite cumbersome for readers to remember the meaning (or state) of 100/101/102.
- /* Ensure initial shared pages are intact. */
- success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
- GUEST_SHARED_ASSERT(uc, success);
- /* Ensure initial private pages are intact/encrypted. */
- success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
- GUEST_SHARED_ASSERT(uc, success);
- /* Ensure host userspace can't read newly-written encrypted data. */
- fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
- GUEST_SHARED_SYNC(uc, 101);
ditto.
- /* Ensure guest can read newly-written shared data from host. */
- success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
- GUEST_SHARED_ASSERT(uc, success);
- /* Ensure host can read newly-written shared data from guest. */
- fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
- GUEST_SHARED_SYNC(uc, 102);
ditto.
+}
+static void +test_common(struct kvm_vm *vm, struct ucall *uc,
uint8_t *shared_buf, uint8_t *private_buf)+{
- bool success;
- /* Initial guest check-in. */
- vcpu_run(vm, VCPU_ID);
- CHECK_SHARED_SYNC(vm, VCPU_ID, uc, 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);
- CHECK_SHARED_SYNC(vm, VCPU_ID, uc, 101);
- /* Ensure host userspace can't read newly-written encrypted data. */
- success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
I am not sure if it is safe here. Since the cache coherency is not there for neither SEV or SEV-ES. Reading confidential memory from host side will generate cache lines that is not coherent with the guest. So might be better to add clfush here?
- 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);
- CHECK_SHARED_SYNC(vm, VCPU_ID, uc, 102);
- /* 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 ucall *uc) +{
- GUEST_SHARED_DONE(uc);
+}
+static void +test_done(struct kvm_vm *vm, struct ucall *uc) +{
- vcpu_run(vm, VCPU_ID);
- CHECK_SHARED_DONE(vm, VCPU_ID, uc);
+}
+static void __attribute__((__flatten__)) +guest_sev_code(struct ucall *uc, uint8_t *shared_buf, uint8_t *private_buf) +{
- uint32_t eax, ebx, ecx, edx;
- uint64_t sev_status;
- guest_test_start(uc);
- /* Check SEV CPUID bit. */
- eax = 0x8000001f;
- ecx = 0;
- cpuid(&eax, &ebx, &ecx, &edx);
- GUEST_SHARED_ASSERT(uc, eax & (1 << 1));
- /* Check SEV MSR bit. */
- sev_status = rdmsr(MSR_AMD64_SEV);
- GUEST_SHARED_ASSERT(uc, (sev_status & 0x1) == 1);
- guest_test_common(uc, shared_buf, private_buf);
- guest_test_done(uc);
+}
+static struct sev_vm * +setup_test_common(void *guest_code, uint64_t policy, struct ucall **uc,
uint8_t **shared_buf, uint8_t **private_buf)+{
- vm_vaddr_t uc_vaddr, shared_vaddr, private_vaddr;
- uint8_t measurement[512];
- struct sev_vm *sev;
- struct kvm_vm *vm;
- int i;
- sev = sev_vm_create(policy, TOTAL_PAGES);
- if (!sev)
return NULL;- vm = sev_get_vm(sev);
- /* 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 ucall buffer. */
- uc_vaddr = ucall_shared_alloc(vm, 1);
- /* 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);
- /* Set up guest params. */
- vcpu_args_set(vm, VCPU_ID, 4, uc_vaddr, shared_vaddr, private_vaddr);
- /*
* Hand these back to test harness, translation is needed now since page* table will be encrypted after SEV VM launch.*/- *uc = addr_gva2hva(vm, uc_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_launch_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);
- return sev;
+}
+static void test_sev(void *guest_code, uint64_t policy) +{
- uint8_t *shared_buf, *private_buf;
- struct sev_vm *sev;
- struct kvm_vm *vm;
- struct ucall *uc;
- sev = setup_test_common(guest_code, policy, &uc, &shared_buf, &private_buf);
- if (!sev)
return;- vm = sev_get_vm(sev);
- /* Guest is ready to run. Do the tests. */
- test_start(vm, uc);
- test_common(vm, uc, shared_buf, private_buf);
- test_done(vm, uc);
- 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;
+}
2.25.1