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Date: Sat, 13 Aug 2016 00:31:44 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH for-2.7 2/4] virtio: decrement vq->inuse in
 virtqueue_discard()
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To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>, gaudenz@debian.org

On Fri, Aug 12, 2016 at 04:32:56PM +0100, Stefan Hajnoczi wrote:
> virtqueue_descard()

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.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

With the correction above

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>


> ---
>  hw/virtio/virtio.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index 4df8274..00158b6 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);
>  }
>  
> -- 
> 2.7.4