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Date: Fri, 10 Jun 2011 11:30:49 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
        efault@gmx.de, Arne Jansen <lists@die-jansens.de>
Subject: Re: [PATCH 1/3] printk: Release console_sem after logbuf_lock
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> >   => only a 'there be dragons' mental marker
> 
> Right, my reply was that I couldn't convince myself unlock order 
> could make a difference, but clearly I can easily have missed 
> something subtle.
> 
> > and i have to say that when i found a boot lockup during testing 
> > i was not surprised very much :)
> 
> But you found a lockup on the second patch, not this one.

Yeah, it's not like my mental markers are overly precise! ;-)

> Also, this patch is important for #3, where we want to take 
> logbuf_lock under the semaphore internal lock, that too would 
> preclude us doing that up() in the old location.

Yeah. I'm not against it or anything (hey i suggested the whole 
thing), but i'll be testing this through carefully.

Thanks,

	Ingo