[PATCH v2 7/7] KVM: selftests: Add hyperv_cpuid test

Vitaly Kuznetsov
2018-12-10T17:22:30Z

Add a simple (and stupid) hyperv_cpuid test: check that we got the
expected number of entries with and without Enlightened VMCS enabled
and that all currently reserved fields are zeroed.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
Changes since v1:
- Check for -E2BIG
---
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/x86_64/hyperv_cpuid.c | 157 ++++++++++++++++++
2 files changed, 158 insertions(+)
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 01a219229238..a5f0f11f4381 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -14,6 +14,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/vmx_tsc_adjust_test
TEST_GEN_PROGS_x86_64 += x86_64/cr4_cpuid_sync_test
TEST_GEN_PROGS_x86_64 += x86_64/state_test
TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test
+TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid
TEST_GEN_PROGS_x86_64 += dirty_log_test

TEST_GEN_PROGS_aarch64 += dirty_log_test
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c b/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c
new file mode 100644
index 000000000000..264425f75806
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test for x86 KVM_CAP_HYPERV_CPUID
+ *
+ * Copyright (C) 2018, Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ */
+
+#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"
+
+#define VCPU_ID 0
+
+static void guest_code(void)
+{
+}
+
+static void test_hv_cpuid(struct kvm_cpuid2 *hv_cpuid_entries,
+ int evmcs_enabled)
+{
+ int i;
+
+ if (!evmcs_enabled)
+ TEST_ASSERT(hv_cpuid_entries->nent == 6,
+ "KVM_GET_SUPPORTED_HV_CPUID should return 6 entries"
+ " when Enlightened VMCS is disabled (returned %d)",
+ hv_cpuid_entries->nent);
+ else
+ TEST_ASSERT(hv_cpuid_entries->nent == 7,
+ "KVM_GET_SUPPORTED_HV_CPUID should return 7 entries"
+ " when Enlightened VMCS is enabled (returned %d)",
+ hv_cpuid_entries->nent);
+
+ for (i = 0; i < hv_cpuid_entries->nent; i++) {
+ struct kvm_cpuid_entry2 *entry = &hv_cpuid_entries->entries[i];
+
+ TEST_ASSERT((entry->function >= 0x40000000) &&
+ (entry->function <= 0x4000000A),
+ "function %lx is our of supported range",
+ entry->function);
+
+ TEST_ASSERT(entry->index == 0,
+ ".index field should be zero");
+
+ TEST_ASSERT(entry->index == 0,
+ ".index field should be zero");
+
+ TEST_ASSERT(entry->flags == 0,
+ ".flags field should be zero");
+
+ TEST_ASSERT(entry->padding[0] == entry->padding[1]
+ == entry->padding[2] == 0,
+ ".index field should be zero");
+
+ /*
+ * If needed for debug:
+ * fprintf(stdout,
+ * "CPUID%lx EAX=0x%lx EBX=0x%lx ECX=0x%lx EDX=0x%lx\n",
+ * entry->function, entry->eax, entry->ebx, entry->ecx,
+ * entry->edx);
+ */
+ }
+
+}
+
+void test_hv_cpuid_e2big(struct kvm_vm *vm)
+{
+ static struct kvm_cpuid2 cpuid = {.nent = 0};
+ int ret;
+
+ ret = _vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
+
+ TEST_ASSERT(ret == -1 && errno == E2BIG,
+ "KVM_GET_SUPPORTED_HV_CPUID didn't fail with -E2BIG when"
+ " it should have: %d %d", ret, errno);
+}
+
+
+struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(struct kvm_vm *vm)
+{
+ int nent = 20; /* should be enough */
+ static struct kvm_cpuid2 *cpuid;
+ int ret;
+
+ cpuid = malloc(sizeof(*cpuid) + nent * sizeof(struct kvm_cpuid_entry2));
+
+ if (!cpuid) {
+ perror("malloc");
+ abort();
+ }
+
+ cpuid->nent = nent;
+
+ vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
+
+ return cpuid;
+}
+
+
+int main(int argc, char *argv[])
+{
+ struct kvm_vm *vm;
+ int rv;
+ uint16_t evmcs_ver;
+ struct kvm_cpuid2 *hv_cpuid_entries;
+ struct kvm_enable_cap enable_evmcs_cap = {
+ .cap = KVM_CAP_HYPERV_ENLIGHTENED_VMCS,
+ .args[0] = (unsigned long)&evmcs_ver
+ };
+
+ /* Tell stdout not to buffer its content */
+ setbuf(stdout, NULL);
+
+ rv = kvm_check_cap(KVM_CAP_HYPERV_CPUID);
+ if (!rv) {
+ fprintf(stderr,
+ "KVM_CAP_HYPERV_CPUID not supported, skip test\n");
+ exit(KSFT_SKIP);
+ }
+
+ /* Create VM */
+ vm = vm_create_default(VCPU_ID, 0, guest_code);
+
+ test_hv_cpuid_e2big(vm);
+
+ hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
+ if (!hv_cpuid_entries)
+ return 1;
+
+ test_hv_cpuid(hv_cpuid_entries, 0);
+
+ free(hv_cpuid_entries);
+
+ vcpu_ioctl(vm, VCPU_ID, KVM_ENABLE_CAP, &enable_evmcs_cap);
+
+ hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
+ if (!hv_cpuid_entries)
+ return 1;
+
+ test_hv_cpuid(hv_cpuid_entries, 1);
+
+ free(hv_cpuid_entries);
+
+ kvm_vm_free(vm);
+
+ return 0;
+}
--
2.19.2