Quoting Michael S. Tsirkin (2013-08-12 07:02:42)
> From: Stefan Hajnoczi <stefa...@redhat.com>
>
> When the dataplane thread stops, its vring.c implementation synchronizes
> vring state back to virtio.c so we can continue emulating the virtio
> device.
>
> This patch ensures that virtio.c's signalled_used_valid flag is reset so
> that we do not suppress guest notifications due to stale signalled_used
> values.
>
> Suggested-by: Kevin Wolf <kw...@redhat.com>
> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
> Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
Is this applicable for qemu-stable? It's a dependency of 4/4 of this series
which I'm planning on pulling in.
> ---
> hw/virtio/dataplane/vring.c | 1 +
> hw/virtio/virtio.c | 5 +++++
> include/hw/virtio/virtio.h | 1 +
> 3 files changed, 7 insertions(+)
>
> diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
> index 82cc151..351a343 100644
> --- a/hw/virtio/dataplane/vring.c
> +++ b/hw/virtio/dataplane/vring.c
> @@ -52,6 +52,7 @@ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
> {
> virtio_queue_set_last_avail_idx(vdev, n, vring->last_avail_idx);
> + virtio_queue_invalidate_signalled_used(vdev, n);
>
> hostmem_finalize(&vring->hostmem);
> }
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index 09f62c6..706bdf4 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -1059,6 +1059,11 @@ void virtio_queue_set_last_avail_idx(VirtIODevice
> *vdev, int n, uint16_t idx)
> vdev->vq[n].last_avail_idx = idx;
> }
>
> +void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n)
> +{
> + vdev->vq[n].signalled_used_valid = false;
> +}
> +
> VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n)
> {
> return vdev->vq + n;
> diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
> index d7e9e0f..a90522d 100644
> --- a/include/hw/virtio/virtio.h
> +++ b/include/hw/virtio/virtio.h
> @@ -237,6 +237,7 @@ hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int
> n);
> hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n);
> uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
> void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t
> idx);
> +void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
> VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
> uint16_t virtio_get_queue_index(VirtQueue *vq);
> int virtio_queue_get_id(VirtQueue *vq);
> --
> MST
