Re: xdp on virtio_net

[Julien Desfossez <ju@klipix.org>]

On 10-Apr-2017 02:45:10 PM, David Ahern wrote:
> On 4/10/17 2:43 PM, Jesper Dangaard Brouer wrote:
> >> So now, all I need is to make this check pass:
> >> if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
> >>     virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
> >>     virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
> >>     virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
> >> 	netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n");
> >> 	return -EOPNOTSUPP;
> >> }
> >>
> >> I know running ethtool commands to disable those features does not change the
> >> result.
> >>
> >> If you have an idea on how to solve this problem that would be great.
> > 
> > Maybe someone on the xdp-newbies@vger.kernel.org list can help?
> > 
> 
> Pass this on the qemu command line for the device you want to run xdp:
> 
> "gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off,guest_ufo=off"

Awesome, it works !

If others want to do it with libvirt/virsh instead of the qemu command line,
here is the right incantation to add to the "interface" section (with 4 vCPUs):
<driver name='vhost' queues='8'>
    <host tso4='off' tso6='off' ecn='off' ufo='off'/>
    <guest tso4='off' tso6='off' ecn='off' ufo='off'/>
</driver>

Thanks !

Julien