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Message-ID: <1328116594.1882.12.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC>
Subject: Re: Module/kthread/printk question/problem
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Dmitry Antipov <dmitry.antipov@linaro.org>
Cc: linux-kernel@vger.kernel.org
Date: Wed, 01 Feb 2012 18:16:34 +0100
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Le mercredi 01 février 2012 à 20:35 +0400, Dmitry Antipov a écrit :
> On 02/01/2012 08:31 PM, Eric Dumazet wrote:
> 
> > Race is here :
> >
> > Here you allow testmod_exit() to continue, while _this_ thread has not
> > yet exited.
> >
> > And if this thread is preempted a litle bit, its code already was freed.
> > ->  crash.
> 
> I realize this, but there was a second part of the question: what's the
> better way to ensure that all test/X threads are really gone at some point of
> testmod_exit()?
> 

You could use kthread_stop() 

This way you can control all your kernel threads really exited before
module cleanup.