On Wed, Oct 13, 2021 at 6:35 AM Jason Wang <jasow...@redhat.com> wrote:
>
>
> 在 2021/10/1 下午3:05, Eugenio Pérez 写道:
> > Signed-off-by: Eugenio Pérez <epere...@redhat.com>
> > ---
> > hw/virtio/vhost-shadow-virtqueue.c | 11 ++++++++++-
> > 1 file changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/virtio/vhost-shadow-virtqueue.c
> > b/hw/virtio/vhost-shadow-virtqueue.c
> > index df7e6fa3ec..775f8d36a0 100644
> > --- a/hw/virtio/vhost-shadow-virtqueue.c
> > +++ b/hw/virtio/vhost-shadow-virtqueue.c
> > @@ -173,6 +173,15 @@ static void vhost_svq_add(VhostShadowVirtqueue *svq,
> > VirtQueueElement *elem)
> > svq->ring_id_maps[qemu_head] = elem;
> > }
> >
> > +static void vhost_svq_kick(VhostShadowVirtqueue *svq)
> > +{
> > + /* Make sure we are reading updated device flag */
>
>
> I guess this would be better:
>
> /* We need to expose available array entries before checking used
> * flags. */
>
> (Borrowed from kernel codes).
>
> Thanks
>
Right, I will replace it, thanks!
>
> > + smp_mb();
> > + if (!(svq->vring.used->flags & VRING_USED_F_NO_NOTIFY)) {
> > + event_notifier_set(&svq->kick_notifier);
> > + }
> > +}
> > +
> > /* Handle guest->device notifications */
> > static void vhost_handle_guest_kick(EventNotifier *n)
> > {
> > @@ -197,7 +206,7 @@ static void vhost_handle_guest_kick(EventNotifier *n)
> > }
> >
> > vhost_svq_add(svq, elem);
> > - event_notifier_set(&svq->kick_notifier);
> > + vhost_svq_kick(svq);
> > }
> >
> > virtio_queue_set_notification(svq->vq, true);
>
