[PATCH v3 20/21] KVM: selftests: Add negative testcase for PEBS format in PERF_CAPABILITIES

From: Sean Christopherson
Date: Fri Mar 10 2023 - 19:49:19 EST


Expand the immutable features sub-test for PERF_CAPABILITIES to verify
KVM rejects any attempt to use a PEBS format other than the host's.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
index 38aec88d733b..29aaa0419294 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
@@ -191,6 +191,16 @@ static void test_immutable_perf_capabilities(union perf_capabilities host_cap)
val.lbr_format, host_cap.lbr_format);
}

+ /* Ditto for the PEBS format. */
+ for (val.pebs_format = 1; val.pebs_format; val.pebs_format++) {
+ if (val.pebs_format == host_cap.pebs_format)
+ continue;
+
+ r = _vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, val.capabilities);
+ TEST_ASSERT(!r, "Bad PEBS FMT = 0x%x didn't fail, host = 0x%x",
+ val.pebs_format, host_cap.pebs_format);
+ }
+
kvm_vm_free(vm);
}

--
2.40.0.rc1.284.g88254d51c5-goog