netconsole: don't call __netpoll_cleanup() while atomic (3f315bef) · Commits · 戴 / test

__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>

drivers/net/netconsole.c

+9 −6

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

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