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Subject: RE: [PATCH] printk: fixing the deadlock when calling printk in nmi
 handle
From: Peter Zijlstra <peterz@infradead.org>
To: "Liu, Chuansheng" <chuansheng.liu@intel.com>
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Date: Wed, 04 Jul 2012 16:09:17 +0200
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On Wed, 2012-07-04 at 15:39 +0200, Peter Zijlstra wrote:
> > Anyway, in nmi handler, calling printk is dangerous. This patch is for this case.
> 
> But its ugly and decreases reliability..  Your 'solution' is to
> basically ignore serialization and pray, that's not a solution, that's
> gambling. 

If you want to fix it, do something like:

  http://marc.info/?l=linux-kernel&m=132446646923333