vhost_net: handle polling errors when setting backend

[~andy/linux] / drivers / vhost / net.c

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index d10ad6f8df7e2289cda2b2b06f5ebccc2da513e5..959b1cd89e6a5be5a402a79089077609f8e30716 100644 (file)
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -165,12 +165,16 @@ static void tx_poll_stop(struct vhost_net *net)
 }
 
 /* Caller must have TX VQ lock */
-static void tx_poll_start(struct vhost_net *net, struct socket *sock)
+static int tx_poll_start(struct vhost_net *net, struct socket *sock)
 {
+       int ret;
+
        if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED))
-               return;
-       vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file);
-       net->tx_poll_state = VHOST_NET_POLL_STARTED;
+               return 0;
+       ret = vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file);
+       if (!ret)
+               net->tx_poll_state = VHOST_NET_POLL_STARTED;
+       return ret;
 }
 
 /* In case of DMA done not in order in lower device driver for some reason.
@@ -642,20 +646,23 @@ static void vhost_net_disable_vq(struct vhost_net *n,
                vhost_poll_stop(n->poll + VHOST_NET_VQ_RX);
 }
 
-static void vhost_net_enable_vq(struct vhost_net *n,
+static int vhost_net_enable_vq(struct vhost_net *n,
                                struct vhost_virtqueue *vq)
 {
        struct socket *sock;
+       int ret;
 
        sock = rcu_dereference_protected(vq->private_data,
                                         lockdep_is_held(&vq->mutex));
        if (!sock)
-               return;
+               return 0;
        if (vq == n->vqs + VHOST_NET_VQ_TX) {
                n->tx_poll_state = VHOST_NET_POLL_STOPPED;
-               tx_poll_start(n, sock);
+               ret = tx_poll_start(n, sock);
        } else
-               vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file);
+               ret = vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file);
+
+       return ret;
 }
 
 static struct socket *vhost_net_stop_vq(struct vhost_net *n,
@@ -833,7 +840,9 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
                r = vhost_init_used(vq);
                if (r)
                        goto err_used;
-               vhost_net_enable_vq(n, vq);
+               r = vhost_net_enable_vq(n, vq);
+               if (r)
+                       goto err_used;
 
                oldubufs = vq->ubufs;
                vq->ubufs = ubufs;