Subject: Re: [PATCH net] virtio-net: alloc big buffers also when guest can receive UFO

From: "Michael S. Tsirkin" <[email-masked]>
Date: Wed, 12 Feb 2014 13:59:01 +0200

On Wed, Feb 12, 2014 at 01:43:28PM +0800, Jason Wang wrote:
> We should alloc big buffers also when guest can receive UFO
> pakcets. Otherwise the big packets will be truncated when mergeable rx
> buffer is disabled.

Not truncated, they will be dropped.

> Fixes 5c5167515d80f78f6bb538492c423adcae31ad65
> (virtio-net: Allow UFO feature to be set and advertised.)
>
> Cc: Rusty Russell <[email-masked]>
> Cc: Michael S. Tsirkin <[email-masked]>
> Cc: Sridhar Samudrala <[email-masked]>
> Signed-off-by: Jason Wang <[email-masked]>

Acked-by: Michael S. Tsirkin <[email-masked]>

for patch but please fix commit message.

> ---
>  drivers/net/virtio_net.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index d75f8ed..5632a99 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -1711,7 +1711,8 @@ static int virtnet_probe(struct virtio_device *vdev)
>  	/* If we can receive ANY GSO packets, we must allocate large ones. */
>  	if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
>  	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
> -	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
> +	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
> +	    virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
>  		vi->big_packets = true;
>  
>  	if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
> -- 
> 1.8.3.2