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Subject: Re: USB mass storage and ARM cache coherency
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Paul Mundt <lethal@linux-sh.org>
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Date: Fri, 12 Mar 2010 08:44:31 +1100
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On Wed, 2010-03-10 at 12:52 +0900, Paul Mundt wrote:
> Well, it does start to get a bit painful with sparsemem section or
> NUMA
> node IDs also digging in to the page flags on 32-bit.. the benefits
> would
> have to be pretty compelling to offset the pain. 

Unless we play a dangerous trick and re-use another flag that isn't
meaningful for allocated pages... maybe PG_buddy ? Or do I miss
something about that guy semantics ?

Cheers,
Ben.