Re: [PATCH v2 09/13] vdpa net: block migration if the device has CVQ

[Jason Wang]

在 2023/2/22 15:28, Eugenio Perez Martin 写道:
> On Wed, Feb 22, 2023 at 5:01 AM Jason Wang <jasowang@redhat.com> wrote:
> > 在 2023/2/8 17:42, Eugenio Pérez 写道:
> > > Devices with CVQ needs to migrate state beyond vq state.  Leaving this
> > > to future series.
> >
> > I may miss something but what is missed to support CVQ/MQ?
> To restore all the device state set by CVQ in the migration source
> (MAC, MQ, ...) before data vqs start. We don't have a reliable way to
> not start data vqs until the device [1].
>
> Thanks!
>
> [1] https://lists.gnu.org/archive/html/qemu-devel/2023-01/msg02652.html


Right. It might be mention this defect in either the change log or 
somewhere in the code as a comment.

(Btw, I think we should fix those vDPA drivers).

Thanks


> > Thanks
> >
> >
> > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
> > > ---
> > >    net/vhost-vdpa.c | 6 ++++++
> > >    1 file changed, 6 insertions(+)
> > >
> > > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> > > index bca13f97fd..309861e56c 100644
> > > --- a/net/vhost-vdpa.c
> > > +++ b/net/vhost-vdpa.c
> > > @@ -955,11 +955,17 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char 
> > > *name,
> > >        }
> > >
> > >        if (has_cvq) {
> > > +        VhostVDPAState *s;
> > > +
> > >            nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
> > >                                     vdpa_device_fd, i, 1, false,
> > >                                     opts->x_svq, iova_range);
> > >            if (!nc)
> > >                goto err;
> > > +
> > > +        s = DO_UPCAST(VhostVDPAState, nc, nc);
> > > +        error_setg(&s->vhost_vdpa.dev->migration_blocker,
> > > +                   "net vdpa cannot migrate with MQ feature");
> > >        }
> > >
> > >        return 0;