Currently, KVM hides the STALL_SLOT event for guests if the host PMU version is PMUv3p4 or newer, as PMMIR_EL1 is handled as RAZ for the guests. But, this should be based on the guests' PMU version (instead of the host PMU version), as an older PMU that doesn't support PMMIR_EL1 could support the STALL_SLOT event, according to the Arm ARM. Exposing the STALL_SLOT event without PMMIR_EL1 won't be very useful anyway though. Stop advertising the STALL_SLOT event for guests unconditionally, rather than fixing or keeping the inaccurate checking to advertise the event for the case, where it is not very useful. Suggested-by: Oliver Upton <oliver.upton@xxxxxxxxx> Signed-off-by: Reiji Watanabe <reijiw@xxxxxxxxxx> --- arch/arm64/kvm/pmu-emul.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index f0cbc9024bb7..68f44f893b44 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -754,8 +754,7 @@ u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) * Don't advertise STALL_SLOT, as PMMIR_EL0 is handled * as RAZ */ - if (vcpu->kvm->arch.arm_pmu->pmuver >= ID_AA64DFR0_EL1_PMUVer_V3P4) - val &= ~BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32); + val &= ~BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32); base = 32; } -- 2.41.0.585.gd2178a4bd4-goog
