[PATCH 7/9] KVM: selftests: Test consistency of PMU MSRs with AMD PMU version

From: Jinrong Liang
Date: Tue Nov 21 2023 - 06:56:04 EST


From: Jinrong Liang <cloudliang@xxxxxxxxxxx>

Add AMD test case to check that KVM accurately accesses the MSRs
supported by the AMD PMU version.

Signed-off-by: Jinrong Liang <cloudliang@xxxxxxxxxxx>
---
.../selftests/kvm/x86_64/pmu_counters_test.c | 45 +++++++++++++++++++
1 file changed, 45 insertions(+)

diff --git a/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c b/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
index b1502a446a55..07cb9694e225 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
@@ -819,6 +819,50 @@ static void test_amd_counters_num(void)
}
}

+static void guest_test_amd_pmu_version(void)
+{
+ bool expect_gp = !this_cpu_has(X86_FEATURE_PERFMON_V2);
+ uint8_t vector;
+ uint64_t val;
+
+ guest_wr_rd_amd_counters(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR,
+ expect_gp, 0);
+ guest_wr_rd_amd_counters(MSR_AMD64_PERF_CNTR_GLOBAL_CTL,
+ expect_gp, 0);
+
+ /*
+ * Attempt to write to MSR_AMD64_PERF_CNTR_GLOBAL_STATUS register, which
+ * will trigger a #GP exception. Because MSR_AMD64_PERF_CNTR_GLOBAL_STATUS
+ * is read-only.
+ */
+ vector = wrmsr_safe(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS, 0);
+ GUEST_ASSERT_PMC_MSR_ACCESS(WRMSR, MSR_AMD64_PERF_CNTR_GLOBAL_STATUS,
+ true, vector);
+
+ vector = rdmsr_safe(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS, &val);
+ GUEST_ASSERT_PMC_MSR_ACCESS(RDMSR, MSR_AMD64_PERF_CNTR_GLOBAL_STATUS,
+ expect_gp, vector);
+
+ GUEST_DONE();
+}
+
+static void test_amd_pmu_version(void)
+{
+ bool kvm_pmu_is_perfmonv2 = kvm_cpu_has(X86_FEATURE_PERFMON_V2);
+ struct kvm_vcpu *vcpu;
+ struct kvm_vm *vm;
+ unsigned int i;
+
+ for (i = 0; i <= kvm_pmu_is_perfmonv2; i++) {
+ vm = pmu_vm_create_with_one_vcpu(&vcpu, guest_test_amd_pmu_version);
+
+ vcpu_set_or_clear_cpuid_feature(vcpu, X86_FEATURE_PERFMON_V2, i);
+
+ run_vcpu(vcpu);
+ kvm_vm_free(vm);
+ }
+}
+
int main(int argc, char *argv[])
{
TEST_REQUIRE(kvm_is_pmu_enabled());
@@ -836,6 +880,7 @@ int main(int argc, char *argv[])
} else if (host_cpu_is_amd) {
test_amd_zen_events();
test_amd_counters_num();
+ test_amd_pmu_version();
} else {
TEST_FAIL("Unknown CPU vendor");
}
--
2.39.3