This reverts commit fe53538069bb4f625bc8734103ba044a83138fea. Restore PMU event teardown before system-register reset so existing perf events cannot retain configuration from the previous run. All counters are disabled by the reset PMCR_EL0 and MDCR_EL2 values, so reset does not need to request a PMU reload.
Assisted-by: Codex:gpt-6-astra Signed-off-by: Akihiko Odaki <[email protected]> --- arch/arm64/kvm/pmu-emul.c | 14 ++++++++++++++ arch/arm64/kvm/reset.c | 3 +++ arch/arm64/kvm/sys_regs.c | 3 --- include/kvm/arm_pmu.h | 2 ++ 4 files changed, 19 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index a5ccb6ae44d5..14fcdbdb4587 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -258,6 +258,20 @@ void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu) pmu->pmc[i].idx = i; } +/** + * kvm_pmu_vcpu_reset - reset pmu state for cpu + * @vcpu: The vcpu pointer + * + */ +void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) +{ + unsigned long mask = kvm_pmu_implemented_counter_mask(vcpu); + int i; + + for_each_set_bit(i, &mask, 32) + kvm_pmu_stop_counter(kvm_vcpu_idx_to_pmc(vcpu, i)); +} + /** * kvm_pmu_vcpu_destroy - free perf event of PMU for cpu * @vcpu: The vcpu pointer diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index 10eb7249aa9e..adcb460a5287 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -185,6 +185,9 @@ void kvm_reset_vcpu(struct kvm_vcpu *vcpu) vcpu->arch.reset_state.reset = false; spin_unlock(&vcpu->arch.mp_state_lock); + /* Reset PMU outside of the non-preemptible section */ + kvm_pmu_vcpu_reset(vcpu); + preempt_disable(); loaded = (vcpu->cpu != -1); if (loaded) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 1481dd5c99a8..75624725adf1 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -5388,9 +5388,6 @@ void kvm_reset_sys_regs(struct kvm_vcpu *vcpu) } set_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags); - - if (kvm_vcpu_has_pmu(vcpu)) - kvm_make_request(KVM_REQ_RELOAD_PMU, vcpu); } /** diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 6b4a118d17ca..51f5e4ca3326 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -48,6 +48,7 @@ u64 kvm_pmu_implemented_counter_mask(struct kvm_vcpu *vcpu); u64 kvm_pmu_accessible_counter_mask(struct kvm_vcpu *vcpu); u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1); void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu); +void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu); void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu); void kvm_pmu_reprogram_counter_mask(struct kvm_vcpu *vcpu, u64 val); void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu); @@ -125,6 +126,7 @@ static inline u64 kvm_pmu_accessible_counter_mask(struct kvm_vcpu *vcpu) return 0; } static inline void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu) {} +static inline void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) {} static inline void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu) {} static inline void kvm_pmu_reprogram_counter_mask(struct kvm_vcpu *vcpu, u64 val) {} static inline void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {} -- 2.55.0
