[PATCH v4 14/15] selftests: kvm: add tests for KVM_SEV_INIT2

From: Paolo Bonzini
Date: Mon Mar 18 2024 - 19:36:08 EST


Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/include/kvm_util_base.h | 6 +-
.../selftests/kvm/set_memory_region_test.c | 8 +-
.../selftests/kvm/x86_64/sev_init2_tests.c | 149 ++++++++++++++++++
4 files changed, 156 insertions(+), 8 deletions(-)
create mode 100644 tools/testing/selftests/kvm/x86_64/sev_init2_tests.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 741c7dc16afc..871e2de3eb05 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -120,6 +120,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/tsc_msrs_test
TEST_GEN_PROGS_x86_64 += x86_64/vmx_pmu_caps_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_init2_tests
TEST_GEN_PROGS_x86_64 += x86_64/sev_migrate_tests
TEST_GEN_PROGS_x86_64 += x86_64/sev_smoke_test
TEST_GEN_PROGS_x86_64 += x86_64/amx_test
diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index 3e0db283a46a..7c06ceb36643 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -890,17 +890,15 @@ static inline struct kvm_vm *vm_create_barebones(void)
return ____vm_create(VM_SHAPE_DEFAULT);
}

-#ifdef __x86_64__
-static inline struct kvm_vm *vm_create_barebones_protected_vm(void)
+static inline struct kvm_vm *vm_create_barebones_type(unsigned long type)
{
const struct vm_shape shape = {
.mode = VM_MODE_DEFAULT,
- .type = KVM_X86_SW_PROTECTED_VM,
+ .type = type,
};

return ____vm_create(shape);
}
-#endif

static inline struct kvm_vm *vm_create(uint32_t nr_runnable_vcpus)
{
diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index 06b43ed23580..904d58793fc6 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -339,7 +339,7 @@ static void test_invalid_memory_region_flags(void)

#ifdef __x86_64__
if (kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM))
- vm = vm_create_barebones_protected_vm();
+ vm = vm_create_barebones_type(KVM_X86_SW_PROTECTED_VM);
else
#endif
vm = vm_create_barebones();
@@ -462,7 +462,7 @@ static void test_add_private_memory_region(void)

pr_info("Testing ADD of KVM_MEM_GUEST_MEMFD memory regions\n");

- vm = vm_create_barebones_protected_vm();
+ vm = vm_create_barebones_type(KVM_X86_SW_PROTECTED_VM);

test_invalid_guest_memfd(vm, vm->kvm_fd, 0, "KVM fd should fail");
test_invalid_guest_memfd(vm, vm->fd, 0, "VM's fd should fail");
@@ -471,7 +471,7 @@ static void test_add_private_memory_region(void)
test_invalid_guest_memfd(vm, memfd, 0, "Regular memfd() should fail");
close(memfd);

- vm2 = vm_create_barebones_protected_vm();
+ vm2 = vm_create_barebones_type(KVM_X86_SW_PROTECTED_VM);
memfd = vm_create_guest_memfd(vm2, MEM_REGION_SIZE, 0);
test_invalid_guest_memfd(vm, memfd, 0, "Other VM's guest_memfd() should fail");

@@ -499,7 +499,7 @@ static void test_add_overlapping_private_memory_regions(void)

pr_info("Testing ADD of overlapping KVM_MEM_GUEST_MEMFD memory regions\n");

- vm = vm_create_barebones_protected_vm();
+ vm = vm_create_barebones_type(KVM_X86_SW_PROTECTED_VM);

memfd = vm_create_guest_memfd(vm, MEM_REGION_SIZE * 4, 0);

diff --git a/tools/testing/selftests/kvm/x86_64/sev_init2_tests.c b/tools/testing/selftests/kvm/x86_64/sev_init2_tests.c
new file mode 100644
index 000000000000..fe55aa5a1b04
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/sev_init2_tests.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/kvm.h>
+#include <linux/psp-sev.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <pthread.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "svm_util.h"
+#include "kselftest.h"
+
+#define SVM_SEV_FEAT_DEBUG_SWAP 32u
+
+/*
+ * Some features may have hidden dependencies, or may only work
+ * for certain VM types. Err on the side of safety and don't
+ * expect that all supported features can be passed one by one
+ * to KVM_SEV_INIT2.
+ *
+ * (Well, right now there's only one...)
+ */
+#define KNOWN_FEATURES SVM_SEV_FEAT_DEBUG_SWAP
+
+int kvm_fd;
+u64 supported_vmsa_features;
+bool have_sev_es;
+
+static int __sev_ioctl(int vm_fd, int cmd_id, void *data)
+{
+ struct kvm_sev_cmd cmd = {
+ .id = cmd_id,
+ .data = (uint64_t)data,
+ .sev_fd = open_sev_dev_path_or_exit(),
+ };
+ int ret;
+
+ ret = ioctl(vm_fd, KVM_MEMORY_ENCRYPT_OP, &cmd);
+ TEST_ASSERT(ret < 0 || cmd.error == SEV_RET_SUCCESS,
+ "%d failed: fw error: %d\n",
+ cmd_id, cmd.error);
+
+ return ret;
+}
+
+static void test_init2(unsigned long vm_type, struct kvm_sev_init *init)
+{
+ struct kvm_vm *vm;
+ int ret;
+
+ vm = vm_create_barebones_type(vm_type);
+ ret = __sev_ioctl(vm->fd, KVM_SEV_INIT2, init);
+ TEST_ASSERT(ret == 0,
+ "KVM_SEV_INIT2 return code is %d (expected 0), errno: %d",
+ ret, errno);
+ kvm_vm_free(vm);
+}
+
+static void test_init2_invalid(unsigned long vm_type, struct kvm_sev_init *init, const char *msg)
+{
+ struct kvm_vm *vm;
+ int ret;
+
+ vm = vm_create_barebones_type(vm_type);
+ ret = __sev_ioctl(vm->fd, KVM_SEV_INIT2, init);
+ TEST_ASSERT(ret == -1 && errno == EINVAL,
+ "KVM_SEV_INIT2 should fail, %s.",
+ msg);
+ kvm_vm_free(vm);
+}
+
+void test_vm_types(void)
+{
+ test_init2(KVM_X86_SEV_VM, &(struct kvm_sev_init){});
+
+ /*
+ * TODO: check that unsupported types cannot be created. Probably
+ * a separate selftest.
+ */
+ if (have_sev_es)
+ test_init2(KVM_X86_SEV_ES_VM, &(struct kvm_sev_init){});
+
+ test_init2_invalid(0, &(struct kvm_sev_init){},
+ "VM type is KVM_X86_DEFAULT_VM");
+ if (kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM))
+ test_init2_invalid(KVM_X86_SW_PROTECTED_VM, &(struct kvm_sev_init){},
+ "VM type is KVM_X86_SW_PROTECTED_VM");
+}
+
+void test_flags(uint32_t vm_type)
+{
+ int i;
+
+ for (i = 0; i < 32; i++)
+ test_init2_invalid(vm_type,
+ &(struct kvm_sev_init){ .flags = BIT(i) },
+ "invalid flag");
+}
+
+void test_features(uint32_t vm_type, uint64_t supported_features)
+{
+ int i;
+
+ for (i = 0; i < 64; i++) {
+ if (!(supported_features & (1u << i)))
+ test_init2_invalid(vm_type,
+ &(struct kvm_sev_init){ .vmsa_features = BIT_ULL(i) },
+ "unknown feature");
+ else if (KNOWN_FEATURES & (1u << i))
+ test_init2(vm_type,
+ &(struct kvm_sev_init){ .vmsa_features = BIT_ULL(i) });
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ int kvm_fd = open_kvm_dev_path_or_exit();
+ bool have_sev;
+
+ TEST_REQUIRE(__kvm_has_device_attr(kvm_fd, 0, KVM_X86_SEV_VMSA_FEATURES) == 0);
+ kvm_device_attr_get(kvm_fd, 0, KVM_X86_SEV_VMSA_FEATURES, &supported_vmsa_features);
+
+ have_sev = kvm_cpu_has(X86_FEATURE_SEV);
+ TEST_ASSERT(have_sev == !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_VM)),
+ "sev: KVM_CAP_VM_TYPES (%x) does not match cpuid (checking %x)",
+ kvm_check_cap(KVM_CAP_VM_TYPES), 1 << KVM_X86_SEV_VM);
+
+ TEST_REQUIRE(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_VM));
+ have_sev_es = kvm_cpu_has(X86_FEATURE_SEV_ES);
+
+ TEST_ASSERT(have_sev_es == !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_ES_VM)),
+ "sev-es: KVM_CAP_VM_TYPES (%x) does not match cpuid (checking %x)",
+ kvm_check_cap(KVM_CAP_VM_TYPES), 1 << KVM_X86_SEV_ES_VM);
+
+ test_vm_types();
+
+ test_flags(KVM_X86_SEV_VM);
+ if (have_sev_es)
+ test_flags(KVM_X86_SEV_ES_VM);
+
+ test_features(KVM_X86_SEV_VM, 0);
+ if (have_sev_es)
+ test_features(KVM_X86_SEV_ES_VM, supported_vmsa_features);
+
+ return 0;
+}
--
2.43.0