[PATCH 3/3 V6] selftest: KVM: Add intra host migration

Peter Gonda
2021-08-30T20:57:33Z

Adds testcases for intra host migration for SEV and SEV-ES. Also adds
locking test to confirm no deadlock exists.

---
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/x86_64/sev_vm_tests.c | 152 ++++++++++++++++++
2 files changed, 153 insertions(+)
create mode 100644 tools/testing/selftests/kvm/x86_64/sev_vm_tests.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 5832f510a16c..de6e64d5c9c4 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -71,6 +71,7 @@ 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_vm_tests
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_vm_tests.c b/tools/testing/selftests/kvm/x86_64/sev_vm_tests.c
new file mode 100644
index 000000000000..50a770316628
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/sev_vm_tests.c
@@ -0,0 +1,150 @@
+// 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 "kvm_util.h"
+#include "kselftest.h"
+#include "../lib/kvm_util_internal.h"
+
+#define SEV_DEV_PATH "/dev/sev"
+
+/*
+ * Open SEV_DEV_PATH if available, otherwise exit the entire program.
+ *
+ * Input Args:
+ * flags - The flags to pass when opening SEV_DEV_PATH.
+ *
+ * Return:
+ * The opened file descriptor of /dev/sev.
+ */
+static int open_sev_dev_path_or_exit(int flags)
+{
+ static int fd;
+
+ if (fd != 0)
+ return fd;
+
+ fd = open(SEV_DEV_PATH, flags);
+ if (fd < 0) {
+ print_skip("%s not available, is SEV not enabled? (errno: %d)",
+ SEV_DEV_PATH, errno);
+ exit(KSFT_SKIP);
+ }
+
+ return fd;
+}
+
+static void sev_ioctl(int fd, int cmd_id, void *data)
+{
+ struct kvm_sev_cmd cmd = { 0 };
+ int ret;
+
+ TEST_ASSERT(cmd_id < KVM_SEV_NR_MAX, "Unknown SEV CMD : %d\n", cmd_id);
+
+ cmd.id = cmd_id;
+ cmd.sev_fd = open_sev_dev_path_or_exit(0);
+ cmd.data = (uint64_t)data;
+ ret = ioctl(fd, KVM_MEMORY_ENCRYPT_OP, &cmd);
+ TEST_ASSERT((ret == 0 || cmd.error == SEV_RET_SUCCESS),
+ "%d failed: return code: %d, errno: %d, fw error: %d",
+ cmd_id, ret, errno, cmd.error);
+}
+
+static struct kvm_vm *sev_vm_create(bool es)
+{
+ struct kvm_vm *vm;
+ struct kvm_sev_launch_start start = { 0 };
+ int i;
+
+ vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
+ sev_ioctl(vm->fd, es ? KVM_SEV_ES_INIT : KVM_SEV_INIT, NULL);
+ for (i = 0; i < 3; ++i)
+ vm_vcpu_add(vm, i);
+ start.policy |= (es) << 2;
+ sev_ioctl(vm->fd, KVM_SEV_LAUNCH_START, &start);
+ if (es)
+ sev_ioctl(vm->fd, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL);
+ return vm;
+}
+
+static void test_sev_migrate_from(bool es)
+{
+ struct kvm_vm *vms[3];
+ struct kvm_enable_cap cap = { 0 };
+ int i;
+
+ for (i = 0; i < sizeof(vms) / sizeof(struct kvm_vm *); ++i)
+ vms[i] = sev_vm_create(es);
+
+ cap.cap = KVM_CAP_VM_MIGRATE_ENC_CONTEXT_FROM;
+ for (i = 0; i < sizeof(vms) / sizeof(struct kvm_vm *) - 1; ++i) {
+ cap.args[0] = vms[i]->fd;
+ vm_enable_cap(vms[i + 1], &cap);
+ }
+}
+
+#define LOCK_TESTING_THREADS 3
+
+struct locking_thread_input {
+ struct kvm_vm *vm;
+ int source_fds[LOCK_TESTING_THREADS];
+};
+
+static void *locking_test_thread(void *arg)
+{
+ struct kvm_enable_cap cap = { 0 };
+ int i, j;
+ struct locking_thread_input *input = (struct locking_test_thread *)arg;
+
+ cap.cap = KVM_CAP_VM_MIGRATE_ENC_CONTEXT_FROM;
+
+ for (i = 0; i < 1000; ++i) {
+ j = input->source_fds[i % LOCK_TESTING_THREADS];
+ cap.args[0] = input->source_fds[j];
+ /*
+ * Call IOCTL directly without checking return code. We are
+ * simply trying to confirm there is no deadlock from userspace
+ * not check correctness of migration here.
+ */
+ ioctl(input->vm->fd, KVM_ENABLE_CAP, &cap);
+ }
+}
+
+static void test_sev_migrate_locking(void)
+{
+ struct locking_thread_input input[LOCK_TESTING_THREADS];
+ pthread_t pt[LOCK_TESTING_THREADS];
+ int i;
+
+ for (i = 0; i < LOCK_TESTING_THREADS; ++i) {
+ input[i].vm = sev_vm_create(/* es= */ false);
+ input[0].source_fds[i] = input[i].vm->fd;
+ }
+ memcpy(input[1].source_fds, input[0].source_fds,
+ sizeof(input[1].source_fds));
+ memcpy(input[2].source_fds, input[0].source_fds,
+ sizeof(input[2].source_fds));
+
+ for (i = 0; i < LOCK_TESTING_THREADS; ++i)
+ pthread_create(&pt[i], NULL, locking_test_thread, &input[i]);
+
+ for (i = 0; i < LOCK_TESTING_THREADS; ++i)
+ pthread_join(pt[i], NULL);
+}
+
+int main(int argc, char *argv[])
+{
+ test_sev_migrate_from(/* es= */ false);
+ test_sev_migrate_from(/* es= */ true);
+ test_sev_migrate_locking();
+ return 0;
+}
--
2.33.0.259.gc128427fd7-goog