Re: [PATCH RFC v2 13/13] net: implement UDP tunnel features offloading

[Akihiko Odaki]

On 2025/07/16 19:13, Paolo Abeni wrote:
> On 7/15/25 10:07 AM, Akihiko Odaki wrote:
> > On 2025/07/11 22:02, Paolo Abeni wrote:
> > > When any host or guest GSO over UDP tunnel offload is enabled the
> > > virtio net header includes the additional tunnel-related fields,
> > > update the size accordingly.
> > >
> > > Push the GSO over UDP tunnel offloads all the way down to the tap
> > > device extending the newly introduced NetFeatures struct, and
> > > eventually enable the associated features.
> > >
> > > As per virtio specification, to convert features bit to offload bit,
> > > map the extended features into the reserved range.
> > >
> > > Finally, make the vhost backend aware of the exact header layout, to
> > > copy it correctly. The tunnel-related field are present if either
> > > the guest or the host negotiated any UDP tunnel related feature:
> > > add them to host kernel supported features list, to allow qemu
> > > transfer to such backend the needed information.
> >
> > Please also update: hw/virtio/virtio-qmp.c
>
> Do you mean by adding FEATURE_ENTRY() for
> {GUEST,HOST}_UDP_TUNNEL_GSO{,_CSUM} ?

Yes.

> Such entries are added in patch 8/13 "qmp: update virtio features map to
> support extended features". Even if the features are not supported yet
> in such patch, I think the code could already parse their name.
>
> Do you prefer I move the features entry definition here?

No, I missed what patch 8/13 did. There is no change needed here.

Regards,
Akihiko Odaki