From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] LSM: Add post recvmsg() hook.
Date: Thu, 22 Jul 2010 10:26:37 -0700 (PDT)
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From: David Miller <davem@davemloft.net>
Date: Thu, 22 Jul 2010 10:22:51 -0700 (PDT)

> From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Date: Thu, 22 Jul 2010 21:46:55 +0900
> 
>> David Miller wrote:
>>> > Then, why does below proposal lose information?
>>> 
>>> Peek changes state, now it's possible that two processes end up
>>> receiving the packet.
>> 
>> Indeed. We will need to protect sock->ops->recvmsg() call using a lock like
> 
> But this doesn't matter.

Also, btw, we're not adding a lock to a code path which we've worked
so hard to make largely lockless.  This lock is going to kill
performance.