[PATCH 1/3] KVM: x86/pmu: Ignore pmu->global_ctrl check if vPMU doesn't support global_ctrl

From: Like Xu
Date: Mon May 09 2022 - 06:23:31 EST


From: Like Xu <likexu@xxxxxxxxxxx>

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@xxxxxxxxxxx>
---
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 b82b6709d7a8..cff03baf8921 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -98,6 +98,9 @@ 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);
}

--
2.36.1