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From: Dave McCracken <dave.mccracken@oracle.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: pte_offset_map for ppc assumes HIGHPTE
Date: Wed, 25 Jul 2007 18:30:21 -0500
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On Wednesday 25 July 2007, Benjamin Herrenschmidt wrote:
> Depends... if you have CONFIG_HIGHMEM and not CONFIG_HIGHPTE, you are
> wasting time going through kmap_atomic unnecessarily no ? it will probably
> not do anything because the PTE page is in lowmem but still...

Probably not much time.  You still need to do the page to virtual translation, 
which kmap_atomic does for you.

Dave McCracken