Re: [PATCH net V2] virtio-net: re enable XDP_REDIRECT for mergeable buffer

From: Jesper Dangaard Brouer
Date: Fri Mar 02 2018 - 11:08:10 EST


On Fri, 2 Mar 2018 17:29:14 +0800
Jason Wang <jasowang@xxxxxxxxxx> wrote:

> XDP_REDIRECT support for mergeable buffer was removed since commit
> 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable()
> case"). This is because we don't reserve enough tailroom for struct
> skb_shared_info which breaks XDP assumption. So this patch fixes this
> by reserving enough tailroom and using fixed size of rx buffer.
>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> ---
> Changes from V1:
> - do not add duplicated tracepoint when redirection fails

Acked-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>

I gave it a quick spin on my testlab, and cpumap seems to
work/not-crash now (if I managed to turn back config to
receive_mergeable() correctly ;-)).

--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer