From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Mon, 15 Aug 2016 12:54:16 +0000 (+0100)
Subject: virtio: decrement vq->inuse in virtqueue_discard()
X-Git-Tag: v2.6.2~31
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ca86c04717c23b2155a9366522736995bc9bd772;p=thirdparty%2Fqemu.git

virtio: decrement vq->inuse in virtqueue_discard()

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: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 58a83c61496eeb0d31571a07a51bc1947e3379ac)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 0333bb8bba5..5fbaaaad6e3 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -267,6 +267,7 @@ void virtqueue_discard(VirtQueue *vq, const VirtQueueElement *elem,
                        unsigned int len)
 {
     vq->last_avail_idx--;
+    vq->inuse--;
     virtqueue_unmap_sg(vq, elem, len);
 }