Re: [Qemu-devel] [PATCH for-2.7 2/4] virtio: decrement vq->inuse in virtqueue_discard()

[Cornelia Huck]

On Fri, 12 Aug 2016 16:32:56 +0100
Stefan Hajnoczi  wrote:

> virtqueue_descard() 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 
> ---
>  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);
>  }
> 

Reviewed-by: Cornelia Huck 

Re: [Qemu-devel] [PATCH for-2.7 2/4] virtio: decrement vq->inuse in virtqueue_discard()

[Michael S. Tsirkin]

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 

With the correction above

Reviewed-by: Michael S. Tsirkin 


> ---
>  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

[Qemu-devel] [PATCH for-2.7 2/4] virtio: decrement vq->inuse in virtqueue_discard()

[Stefan Hajnoczi]

virtqueue_descard() 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 
---
 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