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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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On Mon, 2010-05-03 at 09:19 -0500, Xianghua Xiao wrote:

> Ok here is the test result I did this morning, in short with/without
> Ben's patch it will oops if you write to a freed page.

Probably lucky enough that the free_pages() is pushing the stuff out of
the TLB. At least my patch prevents writing to a non-existing hash table
though, thus avoiding memory corruption.

Cheers,
Ben.