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Subject: Re: pte_offset_map for ppc assumes HIGHPTE
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Dave McCracken <dave.mccracken@oracle.com>
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Date: Thu, 26 Jul 2007 10:18:13 +1000
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On Wed, 2007-07-25 at 18:30 -0500, Dave McCracken wrote:
> 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.

Fair enough.

Ben.