Subject: Re: [PATCH v1 0/2] vduse: add support for networking devices

From: "Michael S. Tsirkin" <[email-masked]>
Date: Mon, 3 Jul 2023 17:45:08 -0400

On Mon, Jul 03, 2023 at 09:43:49AM +0200, Maxime Coquelin wrote:
> 
> On 7/3/23 08:44, Jason Wang wrote:
> > On Sun, Jul 2, 2023 at 9:37 PM Michael S. Tsirkin <[email-masked]> wrote:
> > > 
> > > On Tue, Jun 27, 2023 at 01:36:50PM +0200, Maxime Coquelin wrote:
> > > > This small series enables virtio-net device type in VDUSE.
> > > > With it, basic operation have been tested, both with
> > > > virtio-vdpa and vhost-vdpa using DPDK Vhost library series
> > > > adding VDUSE support using split rings layout (merged in
> > > > DPDK v23.07-rc1).
> > > > 
> > > > Control queue support (and so multiqueue) has also been
> > > > tested, but requires a Kernel series from Jason Wang
> > > > relaxing control queue polling [1] to function reliably.
> > > > 
> > > > [1]: https://lore.kernel.org/lkml/[email-masked]/T/
> > > 
> > > Jason promised to post a new version of that patch.
> > > Right Jason?
> > 
> > Yes.
> > 
> > > For now let's make sure CVQ feature flag is off?
> > 
> > We can do that and relax on top of my patch.
> 
> I agree? Do you prefer a features negotiation, or failing init (like
> done for VERSION_1) if the VDUSE application advertises CVQ?
> 
> Thanks,
> Maxime

Unfortunately guests fail probe if feature set is inconsistent.
So I don't think passing through features is a good idea,
you need a list of legal bits. And when doing this,
clear CVQ and everything that depends on it.

> > Thanks
> > 
> > > 
> > > > RFC -> v1 changes:
> > > > ==================
> > > > - Fail device init if it does not support VERSION_1 (Jason)
> > > > 
> > > > Maxime Coquelin (2):
> > > >    vduse: validate block features only with block devices
> > > >    vduse: enable Virtio-net device type
> > > > 
> > > >   drivers/vdpa/vdpa_user/vduse_dev.c | 15 +++++++++++----
> > > >   1 file changed, 11 insertions(+), 4 deletions(-)
> > > > 
> > > > --
> > > > 2.41.0
> > > 
> >