netconsole: don't call __netpoll_cleanup() while atomic

__netpoll_cleanup() is called in netconsole_netdev_event() while holding a
spinlock. Release/acquire the spinlock before/after it and restart the
loop. Also, disable the netconsole completely, because we won't have chance
after the restart of the loop, and might end up in a situation where
nt->enabled == 1 and nt->np.dev == NULL.

Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Veaceslav Falico 2013-03-11 00:21:48 +00:00 committed by David S. Miller
parent 3da889b616
commit 3f315bef23

View File

@ -666,6 +666,7 @@ static int netconsole_netdev_event(struct notifier_block *this,
goto done;
spin_lock_irqsave(&target_list_lock, flags);
restart:
list_for_each_entry(nt, &target_list, list) {
netconsole_target_get(nt);
if (nt->np.dev == dev) {
@ -678,15 +679,17 @@ static int netconsole_netdev_event(struct notifier_block *this,
case NETDEV_UNREGISTER:
/*
* rtnl_lock already held
* we might sleep in __netpoll_cleanup()
*/
if (nt->np.dev) {
__netpoll_cleanup(&nt->np);
dev_put(nt->np.dev);
nt->np.dev = NULL;
}
spin_unlock_irqrestore(&target_list_lock, flags);
__netpoll_cleanup(&nt->np);
spin_lock_irqsave(&target_list_lock, flags);
dev_put(nt->np.dev);
nt->np.dev = NULL;
nt->enabled = 0;
stopped = true;
break;
netconsole_target_put(nt);
goto restart;
}
}
netconsole_target_put(nt);