From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cyrill Gorcunov <gorcunov@gmail.com>
Date: Tue, 20 Oct 2009 05:02:35 +0000
Subject: Re: kernel panic in latest vanilla stable, while using nameif with
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To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Michal Ostrowski <mostrows@gmail.com>, Denys Fedoryschenko <denys@visp.net.lb>, netdev <netdev@vger.kernel.org>, linux-ppp@vger.kernel.org, paulus@samba.org, mostrows@earthlink.net

On 10/20/09, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Michal Ostrowski a =E9crit :
>> Access of po->pppoe_dev is guarded by sk->sk_state & PPPOX_CONNECTED,
>> and all use cases now rely on the socket lock.  Because of this, the
>> ref-count on the namespace held by the socket object suffices to hold
>> the namespace in existence and so we don't need to ref-count the
>> namespace in PPPoE. The flush_lock is gone.
>>
>
> Seems good !
>
> But can we use lock_sock() in __pppoe_xmit() context ?
>

Eric, most probably i miss something, but how lock sock protect us
from mtu changed via sysfs. This action calls change mtu notifier
which doesn't care about sockets at all...