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Subject: Re: PCI PM: Restore standard config registers of all devices early
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Benjamin Herrenschmidt <benh@kernel.crashing.org>,
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Date: Tue, 03 Feb 2009 12:06:55 +0100
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On Tue, 2009-02-03 at 06:06 +0100, Ingo Molnar wrote:
> 
> Mutexes should work just fine in irqs-off sections - they'll safely 
> save/restore interrupts, even the debug variants.

mutex_lock() has might_sleep() which will generate a splat in atomic
contexts.

That said, afaik the acpi code uses semaphores.