diff options
Diffstat (limited to 'net/core/netpoll.c')
| -rw-r--r-- | net/core/netpoll.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 681eeb2b7399..89f5358d7a1b 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -326,6 +326,7 @@ static int netpoll_owner_active(struct net_device *dev) static netdev_tx_t __netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) { netdev_tx_t status = NETDEV_TX_BUSY; + netdev_tx_t ret = NET_XMIT_DROP; struct net_device *dev; unsigned long tries; /* It is up to the caller to keep npinfo alive. */ @@ -334,11 +335,12 @@ static netdev_tx_t __netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) lockdep_assert_irqs_disabled(); dev = np->dev; + rcu_read_lock(); npinfo = rcu_dereference_bh(dev->npinfo); if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) { dev_kfree_skb_irq(skb); - return NET_XMIT_DROP; + goto out; } /* don't get messages out of order, and no recursion */ @@ -377,7 +379,10 @@ static netdev_tx_t __netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) skb_queue_tail(&npinfo->txq, skb); schedule_delayed_work(&npinfo->tx_work,0); } - return NETDEV_TX_OK; + ret = NETDEV_TX_OK; +out: + rcu_read_unlock(); + return ret; } netdev_tx_t netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) @@ -795,6 +800,13 @@ put_noaddr: goto put; netdev_tracker_alloc(ndev, &np->dev_tracker, GFP_KERNEL); rtnl_unlock(); + + /* Make sure all NAPI polls which started before dev->npinfo + * was visible have exited before we start calling NAPI poll. + * NAPI skips locking if dev->npinfo is NULL. + */ + synchronize_rcu(); + return 0; put: |