From fc66cf4790189b5ec4f8b9e8aacc8d37cc8e3daa Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Fri, 17 Apr 2009 19:40:09 -0300 Subject: KVM: Reset PIT irq injection logic when the PIT IRQ is unmasked upstream commit: 4780c65904f0fc4e312ee2da9383eacbe04e61ea While the PIT is masked the guest cannot ack the irq, so the reinject logic will never allow the interrupt to be injected. Fix by resetting the reinjection counters on unmask. Unbreaks Xen. Signed-off-by: Avi Kivity Signed-off-by: Chris Wright --- arch/x86/kvm/i8254.c | 15 +++++++++++++++ arch/x86/kvm/i8254.h | 1 + 2 files changed, 16 insertions(+) (limited to 'arch') diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index 72bd275a9b5c..3dceaefefa3b 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -536,6 +536,16 @@ void kvm_pit_reset(struct kvm_pit *pit) pit->pit_state.irq_ack = 1; } +static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) +{ + struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); + + if (!mask) { + atomic_set(&pit->pit_state.pit_timer.pending, 0); + pit->pit_state.irq_ack = 1; + } +} + struct kvm_pit *kvm_create_pit(struct kvm *kvm) { struct kvm_pit *pit; @@ -584,6 +594,9 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm) kvm_pit_reset(pit); + pit->mask_notifier.func = pit_mask_notifer; + kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); + return pit; } @@ -592,6 +605,8 @@ void kvm_free_pit(struct kvm *kvm) struct hrtimer *timer; if (kvm->arch.vpit) { + kvm_unregister_irq_mask_notifier(kvm, 0, + &kvm->arch.vpit->mask_notifier); mutex_lock(&kvm->arch.vpit->pit_state.lock); timer = &kvm->arch.vpit->pit_state.pit_timer.timer; hrtimer_cancel(timer); diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h index 4178022b97aa..0dfb936877ed 100644 --- a/arch/x86/kvm/i8254.h +++ b/arch/x86/kvm/i8254.h @@ -45,6 +45,7 @@ struct kvm_pit { struct kvm *kvm; struct kvm_kpit_state pit_state; int irq_source_id; + struct kvm_irq_mask_notifier mask_notifier; }; #define KVM_PIT_BASE_ADDRESS 0x40 -- cgit v1.2.3