[PATCH] kvm: fail msi request if !level

["Michael S. Tsirkin" <mst@redhat.com>]

Irqfd sets level for interrupt to 1 and then to 0.
For MSI, check level so that a single message is sent.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 virt/kvm/irq_comm.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index c380bf0..7af18b8 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -139,7 +139,9 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
 		else
 			clear_bit(irq_source_id, irq_state);
 		sig_level = !!(*irq_state);
-	} else /* Deal with MSI/MSI-X */
+	} else if (!level)
+		return ret;
+	else /* Deal with MSI/MSI-X */
 		sig_level = 1;
 
 	/* Not possible to detect if the guest uses the PIC or the
-- 
1.6.2.5