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Date: Fri, 19 Mar 2010 16:43:29 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Ian Campbell <Ian.Campbell@citrix.com>
CC: Yinghai Lu <yinghai@kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>,
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       Peter Zijlstra <peterz@infradead.org>,
       Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH -v3] x86: do not free zero sized per cpu areas
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On 03/19/2010 04:35 PM, Ian Campbell wrote:
> 
> I think Peter means:
> 
> if (start == end)
> return;
> 
> if (WARN_ONCE(start < end, "blah"))
> return;

start > end!

> i.e. silently ignore a zero sized region and verbosely ignore a
> negatively sized one.

Correct.

	-hpa