1 files changed, 76 insertions, 75 deletions

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index e9ab4f0c454c..d10c249bcc8f 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -698,7 +698,6 @@ int netpoll_setup(struct netpoll *np)
         struct net_device *ndev = NULL;
         struct in_device *in_dev;
         struct netpoll_info *npinfo;
-        struct netpoll *npe, *tmp;
         unsigned long flags;
         int err;
 
@@ -710,38 +709,6 @@ int netpoll_setup(struct netpoll *np)
                 return -ENODEV;
         }
 
-        np->dev = ndev;
-        if (!ndev->npinfo) {
-                npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
-                if (!npinfo) {
-                        err = -ENOMEM;
-                        goto put;
-                }
-
-                npinfo->rx_flags = 0;
-                INIT_LIST_HEAD(&npinfo->rx_np);
-
-                spin_lock_init(&npinfo->rx_lock);
-                skb_queue_head_init(&npinfo->arp_tx);
-                skb_queue_head_init(&npinfo->txq);
-                INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
-
-                atomic_set(&npinfo->refcnt, 1);
-        } else {
-                npinfo = ndev->npinfo;
-                atomic_inc(&npinfo->refcnt);
-        }
-
-        npinfo->netpoll = np;
-
-        if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
-            !ndev->netdev_ops->ndo_poll_controller) {
-                printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
-                       np->name, np->dev_name);
-                err = -ENOTSUPP;
-                goto release;
-        }
-
         if (!netif_running(ndev)) {
                 unsigned long atmost, atleast;
 
@@ -755,7 +722,7 @@ int netpoll_setup(struct netpoll *np)
                 if (err) {
                         printk(KERN_ERR "%s: failed to open %s\n",
                                np->name, ndev->name);
-                        goto release;
+                        goto put;
                 }
 
                 atleast = jiffies + HZ/10;
@@ -792,7 +759,7 @@ int netpoll_setup(struct netpoll *np)
                         printk(KERN_ERR "%s: no IP address for %s, aborting\n",
                                np->name, np->dev_name);
                         err = -EDESTADDRREQ;
-                        goto release;
+                        goto put;
                 }
 
                 np->local_ip = in_dev->ifa_list->ifa_local;
@@ -800,6 +767,43 @@ int netpoll_setup(struct netpoll *np)
                 printk(KERN_INFO "%s: local IP %pI4\n", np->name, &np->local_ip);
         }
 
+        np->dev = ndev;
+
+        /* fill up the skb queue */
+        refill_skbs();
+
+        rtnl_lock();
+        if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
+            !ndev->netdev_ops->ndo_poll_controller) {
+                printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
+                       np->name, np->dev_name);
+                err = -ENOTSUPP;
+                goto unlock;
+        }
+
+        if (!ndev->npinfo) {
+                npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
+                if (!npinfo) {
+                        err = -ENOMEM;
+                        goto unlock;
+                }
+
+                npinfo->rx_flags = 0;
+                INIT_LIST_HEAD(&npinfo->rx_np);
+
+                spin_lock_init(&npinfo->rx_lock);
+                skb_queue_head_init(&npinfo->arp_tx);
+                skb_queue_head_init(&npinfo->txq);
+                INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
+
+                atomic_set(&npinfo->refcnt, 1);
+        } else {
+                npinfo = ndev->npinfo;
+                atomic_inc(&npinfo->refcnt);
+        }
+
+        npinfo->netpoll = np;
+
         if (np->rx_hook) {
                 spin_lock_irqsave(&npinfo->rx_lock, flags);
                 npinfo->rx_flags |= NETPOLL_RX_ENABLED;
@@ -807,24 +811,14 @@ int netpoll_setup(struct netpoll *np)
                 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
         }
 
-        /* fill up the skb queue */
-        refill_skbs();
-
         /* last thing to do is link it to the net device structure */
         rcu_assign_pointer(ndev->npinfo, npinfo);
+        rtnl_unlock();
 
         return 0;
 
- release:
-        if (!ndev->npinfo) {
-                spin_lock_irqsave(&npinfo->rx_lock, flags);
-                list_for_each_entry_safe(npe, tmp, &npinfo->rx_np, rx) {
-                        npe->dev = NULL;
-                }
-                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
-
-                kfree(npinfo);
-        }
+unlock:
+        rtnl_unlock();
 put:
         dev_put(ndev);
         return err;
@@ -841,43 +835,50 @@ void netpoll_cleanup(struct netpoll *np)
 {
         struct netpoll_info *npinfo;
         unsigned long flags;
+        int free = 0;
 
-        if (np->dev) {
-                npinfo = np->dev->npinfo;
-                if (npinfo) {
-                        if (!list_empty(&npinfo->rx_np)) {
-                                spin_lock_irqsave(&npinfo->rx_lock, flags);
-                                list_del(&np->rx);
-                                if (list_empty(&npinfo->rx_np))
-                                        npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
-                                spin_unlock_irqrestore(&npinfo->rx_lock, flags);
-                        }
+        if (!np->dev)
+                return;
 
-                        if (atomic_dec_and_test(&npinfo->refcnt)) {
-                                const struct net_device_ops *ops;
+        rtnl_lock();
+        npinfo = np->dev->npinfo;
+        if (npinfo) {
+                if (!list_empty(&npinfo->rx_np)) {
+                        spin_lock_irqsave(&npinfo->rx_lock, flags);
+                        list_del(&np->rx);
+                        if (list_empty(&npinfo->rx_np))
+                                npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
+                        spin_unlock_irqrestore(&npinfo->rx_lock, flags);
+                }
 
-                                ops = np->dev->netdev_ops;
-                                if (ops->ndo_netpoll_cleanup)
-                                        ops->ndo_netpoll_cleanup(np->dev);
+                free = atomic_dec_and_test(&npinfo->refcnt);
+                if (free) {
+                        const struct net_device_ops *ops;
 
-                                rcu_assign_pointer(np->dev->npinfo, NULL);
+                        ops = np->dev->netdev_ops;
+                        if (ops->ndo_netpoll_cleanup)
+                                ops->ndo_netpoll_cleanup(np->dev);
 
-                                /* avoid racing with NAPI reading npinfo */
-                                synchronize_rcu_bh();
+                        rcu_assign_pointer(np->dev->npinfo, NULL);
+                }
+        }
+        rtnl_unlock();
 
-                                skb_queue_purge(&npinfo->arp_tx);
-                                skb_queue_purge(&npinfo->txq);
-                                cancel_rearming_delayed_work(&npinfo->tx_work);
+        if (free) {
+                /* avoid racing with NAPI reading npinfo */
+                synchronize_rcu_bh();
 
-                                /* clean after last, unfinished work */
-                                __skb_queue_purge(&npinfo->txq);
-                                kfree(npinfo);
-                        }
-                }
+                skb_queue_purge(&npinfo->arp_tx);
+                skb_queue_purge(&npinfo->txq);
+                cancel_rearming_delayed_work(&npinfo->tx_work);
 
-                dev_put(np->dev);
+                /* clean after last, unfinished work */
+                __skb_queue_purge(&npinfo->txq);
+                kfree(npinfo);
         }
 
+        dev_put(np->dev);
+
         np->dev = NULL;
 }