diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 0b49739..0934246 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -616,7 +616,7 @@ static int kvm_virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
     VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no);
     EventNotifier *n = virtio_queue_get_guest_notifier(vq);
     VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
-    int ret;
+    int ret = 0;
 
     if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) {
         ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg);
