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Date: Sun, 31 Jul 2005 12:44:18 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [patch] Real-Time Preemption, -RT-2.6.13-rc4-V0.7.52-01
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> because end_buffer_async_read/write use bit_spin_(un)lock and I do not 
> know how those interact with -RT.

bit_spin_lock is preemptible too - but it's not a too nice construct.  
What seems to have happened in your trace is that local_irq_disable() 
was used too in combination with bit-spinlocks, and a spinlock was taken 
from within it. The best fix would be to get rid of bit-spinlocks ...

	Ingo