From 0f1e172b54f7574ca6aa46b851b332896add955f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sun, 13 Nov 2022 16:38:22 +0000 Subject: [PATCH] KVM: arm64: PMU: Only narrow counters that are not 64bit wide The current PMU emulation sometimes narrows counters to 32bit if the counter isn't the cycle counter. As this is going to change with PMUv3p5 where the counters are all 64bit, fix the couple of cases where this happens unconditionally. Signed-off-by: Marc Zyngier Reviewed-by: Reiji Watanabe Link: https://lore.kernel.org/r/20221113163832.3154370-7-maz@kernel.org --- arch/arm64/kvm/pmu-emul.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 9e6bc7edc4de0..1fab889dbc74f 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -151,20 +151,17 @@ static void kvm_pmu_release_perf_event(struct kvm_pmc *pmc) */ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc) { - u64 counter, reg, val; + u64 reg, val; if (!pmc->perf_event) return; - counter = kvm_pmu_get_counter_value(vcpu, pmc->idx); + val = kvm_pmu_get_counter_value(vcpu, pmc->idx); - if (pmc->idx == ARMV8_PMU_CYCLE_IDX) { + if (pmc->idx == ARMV8_PMU_CYCLE_IDX) reg = PMCCNTR_EL0; - val = counter; - } else { + else reg = PMEVCNTR0_EL0 + pmc->idx; - val = lower_32_bits(counter); - } __vcpu_sys_reg(vcpu, reg) = val; @@ -414,7 +411,8 @@ static void kvm_pmu_counter_increment(struct kvm_vcpu *vcpu, /* Increment this counter */ reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1; - reg = lower_32_bits(reg); + if (!kvm_pmu_idx_is_64bit(vcpu, i)) + reg = lower_32_bits(reg); __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) = reg; /* No overflow? move on */ -- 2.30.2