Commit ac16d148 authored May 28, 2013 by Matthias Schiffer Committed by Antonio Quartulli Jun 10, 2013

batman-adv: wait for rtnl in batadv_store_mesh_iface instead of failing if it is taken

The rtnl_lock in batadv_store_mesh_iface has been converted to a rtnl_trylock
some time ago to avoid a possible deadlock between rtnl and s_active on removal
of the sysfs nodes.

The behaviour introduced by that was quite confusing as it could lead to the
sysfs store to fail, making batman-adv setup scripts unreliable. As recently the
sysfs removal was postponed to a worker not running with the rtnl taken, the
deadlock can't occur any more and it is safe to change the trylock back to a
lock to make the sysfs store reliable again.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Reviewed-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>

parent 40edeff6

net/batman-adv/sysfs.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -582,10 +582,7 @@ static ssize_t batadv_store_mesh_iface(struct kobject *kobj,
		(strncmp(hard_iface->soft_iface->name, buff, IFNAMSIZ) == 0))
		goto out;

		if (!rtnl_trylock()) {
		ret = -ERESTARTSYS;
		goto out;
		}
		rtnl_lock();

		if (status_tmp == BATADV_IF_NOT_IN_USE) {
		batadv_hardif_disable_interface(hard_iface,

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