Commit 2382b15b authored Apr 29, 2009 by Bruno Prémont Committed by David S. Miller May 01, 2009

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 <bonbons@linux-vserver.org>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent acda0743

drivers/net/netconsole.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -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);

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