Date: Fri, 25 Sep 2009 11:54:59 -0300
From: Mauro Carvalho Chehab <mchehab@redhat.com>
To: Arjan van de Ven <arjan@infradead.org>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
       bluesmoke-devel@lists.sourceforge.net
Subject: Re: [PATCH 17/63] edac_mce: Add an interface driver to report mce
 errors via edac
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Em Fri, 25 Sep 2009 14:47:20 +0200
Arjan van de Ven <arjan@infradead.org> escreveu:

> On Fri, 25 Sep 2009 09:11:30 -0300
> Mauro Carvalho Chehab <mchehab@redhat.com> wrote:
> 
> > 5) there are very few calls to kernel routines here:
> > list_for_each_entry(), spin_lock_irqsave(), in_unlock_irqrestore(),
> > memcpy(). I don't think any of them will have any problems on working
> > even inside NMI context.
> 
> spinlocks in NMI context don't do what you think they do....
> _irqsave does not disable NMIs so this can deadlock.
> 
> You likely want to use trylock here....

I see. I'll rewrite that part of the code using trylock or RCU.

-- 

Cheers,
Mauro
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