Re: [PATCH net 1/4] virtio-net: correctly redirect linearized packet

Michael S. Tsirkin
2018-05-21T15:03:42Z

On Mon, May 21, 2018 at 04:35:03PM +0800, Jason Wang wrote:
> After a linearized packet was redirected by XDP, we should not go for
> the err path which will try to pop buffers for the next packet and
> increase the drop counter. Fixing this by just drop the page refcnt
> for the original page.
>
> Fixes: 186b3c998c50 ("virtio-net: support XDP_REDIRECT")
> Reported-by: David Ahern <dsahern@gmail.com>
> Tested-by: David Ahern <dsahern@gmail.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>

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

> ---
> drivers/net/virtio_net.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 770422e..c15d240 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -787,7 +787,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
> }
> *xdp_xmit = true;
> if (unlikely(xdp_page != page))
> - goto err_xdp;
> + put_page(page);
> rcu_read_unlock();
> goto xdp_xmit;
> default:
> --
> 2.7.4