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| author | Andrew Jones <drjones@redhat.com> | 2017-07-01 18:26:54 +0200 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2017-07-25 14:18:01 +0100 |
| commit | d9f89b4e9290e46cd9b273e9ad0bff0f93e86fae (patch) | |
| tree | 94f2f88610beefb87a9995c91a9452a867990d3a /include/kvm | |
| parent | 79962a5c8ba5b33f49d88a058e2124bf2ff3c034 (diff) | |
| download | lwn-d9f89b4e9290e46cd9b273e9ad0bff0f93e86fae.tar.gz lwn-d9f89b4e9290e46cd9b273e9ad0bff0f93e86fae.zip | |
KVM: arm/arm64: PMU: Fix overflow interrupt injection
kvm_pmu_overflow_set() is called from perf's interrupt handler,
making the call of kvm_vgic_inject_irq() from it introduced with
"KVM: arm/arm64: PMU: remove request-less vcpu kick" a really bad
idea, as it's quite easy to try and retake a lock that the
interrupted context is already holding. The fix is to use a vcpu
kick, leaving the interrupt injection to kvm_pmu_sync_hwstate(),
like it was doing before the refactoring. We don't just revert,
though, because before the kick was request-less, leaving the vcpu
exposed to the request-less vcpu kick race, and also because the
kick was used unnecessarily from register access handlers.
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'include/kvm')
| -rw-r--r-- | include/kvm/arm_pmu.h | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index f6e030617467..f87fe20fcb05 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -48,7 +48,6 @@ void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu); void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu); void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val); void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val); -void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val); void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu); void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu); bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu); @@ -86,7 +85,6 @@ 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_disable_counter(struct kvm_vcpu *vcpu, u64 val) {} static inline void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) {} -static inline void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val) {} static inline void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {} static inline void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu) {} static inline bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu) |