virtio: ignore corrupted virtqueues rather than spinning.

A corrupt virtqueue (caused by the other end screwing up) can have strange results such as a driver spinning: just bail when we try to get a buffer from a known-broken queue. Signed-off-by: Rusty Russell <[email protected]>
kishon · May 2, 2008 · 5ef8275 · 5ef8275
1 parent 886c35f
commit 5ef8275
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
@@ -184,6 +184,11 @@ static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len)
 
 	START_USE(vq);
 
+	if (unlikely(vq->broken)) {
+		END_USE(vq);
+		return NULL;
+	}
+
 	if (!more_used(vq)) {
 		pr_debug("No more buffers in queue\n");
 		END_USE(vq);