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Subject: Re: [PATCH] Fix DEBUG_PAGEALLOC on 603/e300
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Xianghua Xiao <xiaoxianghua@gmail.com>
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Date: Thu, 29 Apr 2010 08:29:50 +1000
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On Wed, 2010-04-28 at 14:15 -0500, Xianghua Xiao wrote:
> This change works me on a 834x(e300) platform, tested with lmbench and
> a production-ready application with 2.6.33.3.

But have you tested that DEBUG_PAGEALLOC actually works ? :-)

A way to do that is to

	- get_free_pages a page
	- read from it
	- free it
	- write to it

It should oops on the write, and I suspect that without my patch it
doesn't.

Cheers,
Ben.