virtio_net: verify if virtqueue_kick() succeeded
Verify if a host kick succeeded by checking return value of virtqueue_kick().
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index ee02271..ff208d2 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -545,7 +545,8 @@
} while (rq->vq->num_free);
if (unlikely(rq->num > rq->max))
rq->max = rq->num;
- virtqueue_kick(rq->vq);
+ if (unlikely(!virtqueue_kick(rq->vq)))
+ return false;
return !oom;
}
@@ -751,7 +752,7 @@
err = xmit_skb(sq, skb);
/* This should not happen! */
- if (unlikely(err)) {
+ if (unlikely(err) || unlikely(!virtqueue_kick(sq->vq))) {
dev->stats.tx_fifo_errors++;
if (net_ratelimit())
dev_warn(&dev->dev,
@@ -760,7 +761,6 @@
kfree_skb(skb);
return NETDEV_TX_OK;
}
- virtqueue_kick(sq->vq);
/* Don't wait up for transmitted skbs to be freed. */
skb_orphan(skb);
@@ -819,7 +819,8 @@
BUG_ON(virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC)
< 0);
- virtqueue_kick(vi->cvq);
+ if (unlikely(!virtqueue_kick(vi->cvq)))
+ return status == VIRTIO_NET_OK;
/* Spin for a response, the kick causes an ioport write, trapping
* into the hypervisor, so the request should be handled immediately.