From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: [PATCH 4/6] vlan: Optimize multiple unregistration
Date: Thu, 29 Oct 2009 18:25:20 +0100
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Cc: "David S. Miller" <davem@davemloft.net>,
	Linux Netdev List <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet wrote:
> Patrick McHardy a =E9crit :
>=20
>> Indeed, but unregister_vlan_dev() destroys the group once the
>> count has reached zero, so we must not access it after that.
>=20
> Well, I hoped call_rcu() callback doesnt fire and kfree(grp) until we=
 exited
> from unregister_vlan_dev_alls(), with RTNL locked...

The RTNL is a mutex, so it shouldn't prevent call_rcu from firing.