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Tsirkin" , Markus Armbruster , virtualization@lists.linux-foundation.org, Harpreet Singh Anand , Xiao W Wang , Stefan Hajnoczi , Eli Cohen , Eric Blake , Michael Lilja , Stefano Garzarella Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" 在 2021/10/1 下午3:05, Eugenio Pérez 写道: > Signed-off-by: Eugenio Pérez > --- > 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 > + 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);