Re: [PATCH] virtio_ring: fix num_free handling in error case

[Cornelia Huck]

On Fri, 23 Feb 2018 19:41:30 +0800
Tiwei Bie <tiwei.bie@xxxxxxxxx> wrote:

> The vq->vq.num_free hasn't been changed when error happens,
> so it shouldn't be changed when handling the error.
> 
> Fixes: 780bc7903a32 ("virtio_ring: Support DMA APIs")
> Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Tiwei Bie <tiwei.bie@xxxxxxxxx>
> ---
>  drivers/virtio/virtio_ring.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index eb30f3e09a47..71458f493cf8 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -428,8 +428,6 @@ static inline int virtqueue_add(struct virtqueue *_vq,
>  		i = virtio16_to_cpu(_vq->vdev, vq->vring.desc[i].next);
>  	}
>  
> -	vq->vq.num_free += total_sg;
> -
>  	if (indirect)
>  		kfree(desc);
>  

Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>