KVM: Handle spurious acks for PIT interrupts

Spurious acks can be generated, for example if the PIC is being reset.
Handle those acks gracefully rather than flooding the log with warnings.

Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 7d04dd3ef857..c842060c6c04 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -228,7 +228,7 @@ void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian)
 						 irq_ack_notifier);
 	spin_lock(&ps->inject_lock);
 	if (atomic_dec_return(&ps->pit_timer.pending) < 0)
-		WARN_ON(1);
+		atomic_inc(&ps->pit_timer.pending);
 	ps->irq_ack = 1;
 	spin_unlock(&ps->inject_lock);
 }