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Subject: Re: Allocator MAX_ORDER exceeds SECTION_SIZE
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Buesch <mb@bu3sch.de>
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Date: Mon, 11 Jan 2010 07:39:51 +1100
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On Sun, 2010-01-10 at 19:15 +0100, Michael Buesch wrote:
> On Sunday 10 January 2010 14:31:09 Michael Buesch wrote:
> > I get the following compilation failure, if 64k pages is selected
> > on 2.6.32.3 on a PowerMAC config:
> > 
> > include/linux/mmzone.h:947:2: error: #error Allocator MAX_ORDER exceeds SECTION_SIZE
> > 
> > Any idea?
> > 
> 
> Ok, I figured out that lowering CONFIG_FORCE_MAX_ZONEORDER from 13 to 9
> seems to fix the problem.
> That error message could really need some improvement and at least a hint on what to do and why.
> 
> I'm also wondering, if the kconfig entry for CONFIG_FORCE_MAX_ZONEORDER could
> somehow be limited to 9, if 64k pages is enabled.

There's some stuff in there to try to change the max order but KConfig
never quite get it right I think.

Cheers,
Ben.