KVM: Reset PIT irq injection logic when the PIT IRQ is unmasked
[sfrench/cifs-2.6.git] / arch / x86 / kvm / i8254.c
index 72bd275a9b5cee632b393448e325f371610f860b..c13bb92d3157708a52e211b1992a71f45554ffbb 100644 (file)
@@ -201,6 +201,9 @@ static int __pit_timer_fn(struct kvm_kpit_state *ps)
        if (!atomic_inc_and_test(&pt->pending))
                set_bit(KVM_REQ_PENDING_TIMER, &vcpu0->requests);
 
+       if (!pt->reinject)
+               atomic_set(&pt->pending, 1);
+
        if (vcpu0 && waitqueue_active(&vcpu0->wq))
                wake_up_interruptible(&vcpu0->wq);
 
@@ -536,6 +539,16 @@ 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;
@@ -545,9 +558,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm)
        if (!pit)
                return NULL;
 
-       mutex_lock(&kvm->lock);
        pit->irq_source_id = kvm_request_irq_source_id(kvm);
-       mutex_unlock(&kvm->lock);
        if (pit->irq_source_id < 0) {
                kfree(pit);
                return NULL;
@@ -580,10 +591,14 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm)
        pit_state->irq_ack_notifier.gsi = 0;
        pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq;
        kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
+       pit_state->pit_timer.reinject = true;
        mutex_unlock(&pit->pit_state.lock);
 
        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 +607,8 @@ 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);