We get pointer ring from the exported sock, this means we should keep
rx_ring and vq->private synced during both vq stop and backend set,
otherwise we may see stale rx_ring.
Fixes: c67df11f6e480 ("vhost_net: try batch dequing from skb array")
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/vhost/net.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 60f1080..efb9306 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -973,6 +973,7 @@ static struct socket *vhost_net_stop_vq(struct vhost_net *n,
vhost_net_disable_vq(n, vq);
vq->private_data = NULL;
vhost_net_buf_unproduce(nvq);
+ nvq->rx_ring = NULL;
mutex_unlock(&vq->mutex);
return sock;
}
@@ -1162,14 +1163,14 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
vhost_net_disable_vq(n, vq);
vq->private_data = sock;
vhost_net_buf_unproduce(nvq);
- if (index == VHOST_NET_VQ_RX)
- nvq->rx_ring = get_tap_ptr_ring(fd);
r = vhost_vq_init_access(vq);
if (r)
goto err_used;
r = vhost_net_enable_vq(n, vq);
if (r)
goto err_used;
+ if (index == VHOST_NET_VQ_RX)
+ nvq->rx_ring = get_tap_ptr_ring(fd);
oldubufs = nvq->ubufs;
nvq->ubufs = ubufs;
--
2.7.4
