Re: [net PATCH v5 1/6] virtio_net: use dev_kfree_skb for small buffer XDP receive

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Jan 24, 2017 at 02:43:28PM -0500, David Miller wrote:
> From: "Michael S. Tsirkin" <mst@redhat.com>
> Date: Mon, 23 Jan 2017 23:08:35 +0200
> 
> > On Tue, Jan 17, 2017 at 02:19:50PM -0800, John Fastabend wrote:
> >> In the small buffer case during driver unload we currently use
> >> put_page instead of dev_kfree_skb. Resolve this by adding a check
> >> for virtnet mode when checking XDP queue type. Also name the
> >> function so that the code reads correctly to match the additional
> >> check.
> >> 
> >> Fixes: bb91accf2733 ("virtio-net: XDP support for small buffers")
> >> Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
> >> Acked-by: Jason Wang <jasowang@redhat.com>
> > 
> > Acked-by: Michael S. Tsirkin <mst@redhat.com>
> > 
> > I think we definitely want this one in -net as it's
> > a bugfix.
> 
> This whole series is a bug fix, we must have adjust_header XDP
> support in the virtio_net driver before v4.10 goes out, it is
> a requires base feature for XDP.

I have to say device resets outside probe have a huge potential
to uncover hypervisor bugs. I am rather uncomfortable
doing that after -rc1.

How about a module option to disable it by default?
We can then ship a partial implementation in 4.10
and work on completing it in 4.11.

-- 
MST