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Subject: Re: powerpc: should mem_end be assigned to dt_struct_end in
	flatten_device_tree()?
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Roel Kluin <roel.kluin@gmail.com>
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Date: Fri, 15 Jan 2010 13:44:00 +1100
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Cc: linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>
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On Fri, 2010-01-15 at 00:00 +0100, Roel Kluin wrote:
> vi arch/powerpc/kernel/prom_init.c +1961 and note that in
> flatten_device_tree() we do a
> 
>         RELOC(dt_struct_end) = PAGE_ALIGN(mem_start);
> 
> should that maybe be
> 
>         RELOC(dt_struct_end) = PAGE_ALIGN(mem_end);
> 

Nope.

mem_start is a "cursor", it moves as things gets pushed into the flat
device-tree blob. We thus snapshot its value after pushing the last bit
of the structure. mem_end is just the max boundary past which we can no
longer push things.

Cheers,
Ben.