diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c index d98d107efb05..2458a1dc2ba9 100644 --- a/virt/kvm/ioapic.c +++ b/virt/kvm/ioapic.c @@ -97,6 +97,14 @@ static void rtc_irq_eoi_tracking_reset(struct kvm_ioapic *ioapic) bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS); } +static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic); + +static void rtc_status_pending_eoi_check_valid(struct kvm_ioapic *ioapic) +{ + if (WARN_ON(ioapic->rtc_status.pending_eoi < 0)) + kvm_rtc_eoi_tracking_restore_all(ioapic); +} + static void __rtc_irq_eoi_tracking_restore_one(struct kvm_vcpu *vcpu) { bool new_val, old_val; @@ -120,9 +128,8 @@ static void __rtc_irq_eoi_tracking_restore_one(struct kvm_vcpu *vcpu) } else { __clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map); ioapic->rtc_status.pending_eoi--; + rtc_status_pending_eoi_check_valid(ioapic); } - - WARN_ON(ioapic->rtc_status.pending_eoi < 0); } void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu) @@ -149,10 +156,10 @@ static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic) static void rtc_irq_eoi(struct kvm_ioapic *ioapic, struct kvm_vcpu *vcpu) { - if (test_and_clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map)) + if (test_and_clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map)) { --ioapic->rtc_status.pending_eoi; - - WARN_ON(ioapic->rtc_status.pending_eoi < 0); + rtc_status_pending_eoi_check_valid(ioapic); + } } static bool rtc_irq_check_coalesced(struct kvm_ioapic *ioapic) @@ -353,6 +360,12 @@ static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status) ioapic->irr &= ~(1 << irq); if (irq == RTC_GSI && line_status) { + /* + * pending_eoi cannot ever become negative (see + * rtc_status_pending_eoi_check_valid) and the caller + * ensures that it is only called if it is >= zero, namely + * if rtc_irq_check_coalesced returns false). + */ BUG_ON(ioapic->rtc_status.pending_eoi != 0); ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe, ioapic->rtc_status.dest_map);