Messages in this thread Patch in this message | | | From | Eric Auger <> | Subject | [PATCH 1/4] KVM: arm64: pmu: Don't increment SW_INCR if PMCR.E is unset | Date | Fri, 24 Jan 2020 15:25:32 +0100 |
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The specification says PMSWINC increments PMEVCNTR<n>_EL1 by 1 if PMEVCNTR<n>_EL0 is enabled and configured to count SW_INCR.
For PMEVCNTR<n>_EL0 to be enabled, we need both PMCNTENSET to be set for the corresponding event counter but we also need the PMCR.E bit to be set.
Fixes: 7a0adc7064b8 ("arm64: KVM: Add access handler for PMSWINC register") Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> --- virt/kvm/arm/pmu.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c index 8731dfeced8b..c3f8b059881e 100644 --- a/virt/kvm/arm/pmu.c +++ b/virt/kvm/arm/pmu.c @@ -486,6 +486,9 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) if (val == 0) return; + if (!(__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E)) + return; + enable = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0); for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++) { if (!(val & BIT(i))) -- 2.20.1
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