[PATCH 5.10 509/545] KVM: x86/pmu: Ignore pmu->global_ctrl check if vPMU doesnt support global_ctrl

Greg Kroah-Hartman
2022-08-19T16:53:57Z

From: Like Xu <likexu@tencent.com>

[ Upstream commit 98defd2e17803263f49548fea930cfc974d505aa ]

MSR_CORE_PERF_GLOBAL_CTRL is introduced as part of Architecture PMU V2,
as indicated by Intel SDM 19.2.2 and the intel_is_valid_msr() function.

So in the absence of global_ctrl support, all PMCs are enabled as AMD does.

Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20220509102204.62389-1-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/kvm/vmx/pmu_intel.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index e73378b6f10c..f938fc997766 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -104,6 +104,9 @@ static bool intel_pmc_is_enabled(struct kvm_pmc *pmc)
{
struct kvm_pmu *pmu = pmc_to_pmu(pmc);

+ if (pmu->version < 2)
+ return true;
+
return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
}

--
2.35.1