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Date: Fri, 19 Mar 2010 14:42:06 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Yinghai Lu <yinghai@kernel.org>
CC: Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
       linux-kernel@vger.kernel.org, Ian Campbell <ian.campbell@citrix.com>,
       Peter Zijlstra <peterz@infradead.org>,
       Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] x86: do not free zero sized per cpu areas
References: <4B914A61.20409@kernel.org> <4BA3CF67.9000107@kernel.org>
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On 03/19/2010 12:24 PM, Yinghai Lu wrote:
> From: Ian Campbell <ian.campbell@citrix.com>
> 
> This avoids an infinite loop in free_early_partial().
> 
> Add a warning to free_early_partial to catch future problems.

Wouldn't it make more sense to simply make free_early_partial() a noop
for the zero range, instead of pushing all those tests into the callers?
 It still might make sense to have a WARN_ONCE() for a *negative* range,
however...

	-hpa