From 67975901183799af8e93ec60e322f9e2a1940b9b Mon Sep 17 00:00:00 2001 From: Heinz Graalfs Date: Tue, 29 Oct 2013 09:40:02 +1030 Subject: [PATCH] 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 Signed-off-by: Rusty Russell --- drivers/net/virtio_net.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index ee022714ead..ff208d2787d 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -545,7 +545,8 @@ static bool try_fill_recv(struct receive_queue *rq, gfp_t gfp) } 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 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) 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 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) 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 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, 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. -- 2.43.2