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From: Jimi Xenidis <jimix@watson.ibm.com>
Subject: Re: [PATCH] powerpc: Introduce address space "slices"
Date: Mon, 19 Feb 2007 14:57:37 -0500
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On Feb 19, 2007, at 2:42 PM, Benjamin Herrenschmidt wrote:

> On Mon, 2007-02-19 at 08:23 -0500, Jimi Xenidis wrote:
>> Hey Ben,
>> is it your intention to eventually support "/memory@x/
>> ibm,expected#pages" and will these rules effect the kernel's  
>> linear map?
>> My interest is with hypervisors that would like to restrict certain
>> LMBs to 4k so we can do our nasty memory tricks, but still have most
>> of the memory use large pages.
>
> The slices mecanism is strictly a mecanism for dealing with segment
> constraints on userland VMA layout, so I don't think it will have any
> impact either negative or positive on you.
>
> Limiting physical memory to different page sizes is a whole different
> problem that I haven't though about (damn, that would be hard).

Damn, I know, I was hoping you'd be taking care of it. :)

-JX