[PATCH v2] KVM: selftests: x86: Fix test failure on arch lbr capable platforms

* [PATCH v2] KVM: selftests: x86: Fix test failure on arch lbr capable platforms
@ 2022-05-12  8:40 Yang Weijiang
  2022-05-12 13:23 ` Paolo Bonzini
  0 siblings, 1 reply; 2+ messages in thread
From: Yang Weijiang @ 2022-05-12  8:40 UTC (permalink / raw)
  To: pbonzini, likexu, linux-kernel, kvm; +Cc: Yang Weijiang

On Arch LBR capable platforms, LBR_FMT in perf capability msr is 0x3f,
so the last format test will fail. Use a true invalid format(0x30) for
the test if it's running on these platforms. Opportunistically change
the file name to reflect the tests actually carried out.

v2:
Select a true invalid format instead of skipping the test on arch lbr
capable platforms.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
---
 tools/testing/selftests/kvm/Makefile           |  2 +-
 ...vmx_pmu_msrs_test.c => vmx_pmu_caps_test.c} | 18 ++++++++++--------
 2 files changed, 11 insertions(+), 9 deletions(-)
 rename tools/testing/selftests/kvm/x86_64/{vmx_pmu_msrs_test.c => vmx_pmu_caps_test.c} (83%)

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 681b173aa87c..9a1a84803b01 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -81,7 +81,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/xapic_state_test
 TEST_GEN_PROGS_x86_64 += x86_64/xss_msr_test
 TEST_GEN_PROGS_x86_64 += x86_64/debug_regs
 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/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_migrate_tests
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_pmu_msrs_test.c b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
similarity index 83%
rename from tools/testing/selftests/kvm/x86_64/vmx_pmu_msrs_test.c
rename to tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
index 2454a1f2ca0c..97b7fd4a9a3d 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_pmu_msrs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
@@ -1,15 +1,14 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * VMX-pmu related msrs test
+ * Test for VMX-pmu perf capability msr
  *
  * Copyright (C) 2021 Intel Corporation
  *
- * Test to check the effect of various CPUID settings
- * on the MSR_IA32_PERF_CAPABILITIES MSR, and check that
- * whatever we write with KVM_SET_MSR is _not_ modified
- * in the guest and test it can be retrieved with KVM_GET_MSR.
- *
- * Test to check that invalid LBR formats are rejected.
+ * Test to check the effect of various CPUID settings on
+ * MSR_IA32_PERF_CAPABILITIES MSR, and check that what
+ * we write with KVM_SET_MSR is _not_ modified by the guest
+ * and check it can be retrieved with KVM_GET_MSR, also test
+ * the invalid LBR formats are rejected.
  */
 
 #define _GNU_SOURCE /* for program_invocation_short_name */
@@ -107,8 +106,11 @@ int main(int argc, char *argv[])
 	ASSERT_EQ(vcpu_get_msr(vm, VCPU_ID, MSR_IA32_PERF_CAPABILITIES), (u64)host_cap.lbr_format);
 
 	/* testcase 3, check invalid LBR format is rejected */
-	ret = _vcpu_set_msr(vm, 0, MSR_IA32_PERF_CAPABILITIES, PMU_CAP_LBR_FMT);
+	/* Note, on Arch LBR capable platforms, LBR_FMT in perf capability msr is 0x3f,
+	 * to avoid the failure, use a true invalid format 0x30 for the test. */
+	ret = _vcpu_set_msr(vm, 0, MSR_IA32_PERF_CAPABILITIES, 0x30);
 	TEST_ASSERT(ret == 0, "Bad PERF_CAPABILITIES didn't fail.");
 
+	printf("Completed perf capability tests.\n");
 	kvm_vm_free(vm);
 }

base-commit: 672c0c5173427e6b3e2a9bbb7be51ceeec78093a
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread