netconsole: take care of NETDEV_UNREGISTER event

When netconsole is loaded and a network interface fades away (e.g. on rmmod $interface_driver_module) the rmmod remains stuck and some locks are taken that prevent any additional module loading/unloading as well as interface up/down changes. In addition kernel logs (and console) get flooded at 10s interval with [ 122.464065] unregister_netdevice: waiting for eth0 to become free. Usage count = 1 [ 132.704059] unregister_netdevice: waiting for eth0 to become free. Usage count = 1 This patch lets netconsole take NETDEV_UNREGISTER event into account and release the affected interface if it was in use. Signed-off-by: Bruno Prémont <[email protected]> Acked-by: Matt Mackall <[email protected]> Signed-off-by: David S. Miller <[email protected]>
angolini · May 1, 2009 · 2382b15 · 2382b15
1 parent acda074
commit 2382b15
Showing 1 changed file with 10 additions and 1 deletion.
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
@@ -664,7 +664,7 @@ static int netconsole_netdev_event(struct notifier_block *this,
 	struct netconsole_target *nt;
 	struct net_device *dev = ptr;
 
-	if (!(event == NETDEV_CHANGENAME))
+	if (!(event == NETDEV_CHANGENAME || event == NETDEV_UNREGISTER))
 		goto done;
 
 	spin_lock_irqsave(&target_list_lock, flags);
@@ -675,6 +675,15 @@ static int netconsole_netdev_event(struct notifier_block *this,
 			case NETDEV_CHANGENAME:
 				strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
 				break;
+			case NETDEV_UNREGISTER:
+				if (!nt->enabled)
+					break;
+				netpoll_cleanup(&nt->np);
+				nt->enabled = 0;
+				printk(KERN_INFO "netconsole: network logging stopped"
+					", interface %s unregistered\n",
+					dev->name);
+				break;
 			}
 		}
 		netconsole_target_put(nt);