Re: [PATCH RFC v2 04/13] hw/virtio/vhost-shadow-virtqueue: used callback

On Tue, Aug 18, 2026 at 11:23 PM Akihiko Odaki
<[email protected]> wrote:
>
> > +
> > +                if (r < 0) {
> > +                    /* VQ or handler is broken. Do not set guest notifier */
>
> This comment is extraneous. It is obvious that event_notifier_set()
> below is not called, and it is same with the existing error path below.
>
> What matters here is the difference with the existing error path. Why
> doesn't it call virtqueue_fill() nor virtqueue_flush()? They need to be
> addressed here.
>
> Regards,
> Akihiko Odaki
>

Here, apart from not calling event_notifier_set (not notifying the
guest), we are also not calling vhost_svq_enable_notification, so the
device is directed not to send any more call notifications.  If the
guest isn't receiving notifications, and the device isn't sending
them, is there a purpose to flushing the current element?  With the
current implementation, I'm not sure there is a path to re-enable
calls on either the front-end or back-end, but maybe a case could be
made that it's good hygiene to flush the known bad element?  For now,
I will add the calls to add and flush the element

Thank you!
Connor