[PULL,2/2] virtio: decrement vq->inuse in virtqueue_discard()

Commit Message

Michael S. Tsirkin Aug. 23, 2016, 4:34 p.m. UTC

From: Stefan Hajnoczi <[e-mail]>

virtqueue_discard() moves vq->last_avail_idx back so the element can be
popped again.  It's necessary to decrement vq->inuse to avoid "leaking"
the element count.

Cc: [e-mail]
Signed-off-by: Stefan Hajnoczi <[e-mail]>
Reviewed-by: Michael S. Tsirkin <[e-mail]>
Reviewed-by: Cornelia Huck <[e-mail]>
Reviewed-by: Michael S. Tsirkin <[e-mail]>
Signed-off-by: Michael S. Tsirkin <[e-mail]>
---
 hw/virtio/virtio.c | 1 +
 1 file changed, 1 insertion(+)

Patch

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 6105c6e..74c085c 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -268,6 +268,7 @@  void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
                        unsigned int len)
 {
     vq->last_avail_idx--;
+    vq->inuse--;
     virtqueue_unmap_sg(vq, elem, len);
 }