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Subject: Re: [PATCH] powerpc: Introduce address space "slices"
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Jimi Xenidis <jimix@watson.ibm.com>
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Date: Tue, 20 Feb 2007 06:42:37 +1100
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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).

Ben.