From mboxrd@z Thu Jan  1 00:00:00 1970
From: dave.martin@linaro.org (Dave Martin)
Date: Wed, 12 Jan 2011 10:05:19 -0600
Subject: ARM: relocation out of range (when loading a module)
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	<20110111155930.GH11039@n2100.arm.linux.org.uk>
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To: linux-arm-kernel@lists.infradead.org
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On Tue, Jan 11, 2011 at 9:00 PM, Alexander Holler <holler@ahsoftware.de> wrote:
> Hello,

[...]

> ? ? ? ? ? ? ? ?INIT_CALLS
> ? ? ? ? ? ? ? ?CON_INITCALL
> ? ? ? ? ? ? ? ?SECURITY_INITCALL
> + ? ? ? ? ? ? ? /*
> + ? ? ? ? ? ? ? ?* TODO: The size of INIT_RAM_FS could easily reach a
> + ? ? ? ? ? ? ? ?* point (~16MB) when loading modules will fail because
> + ? ? ? ? ? ? ? ?* relocations will be out of range. So this place here
> + ? ? ? ? ? ? ? ?* isn't the best one.
> + ? ? ? ? ? ? ? ?*/
> ? ? ? ? ? ? ? ?INIT_RAM_FS

In general, do we expect always to be able to avoid the situation
where branches in the kernel may need to cover too large a range ...
and is there any strategy for working aroung it?

If we have problems branching from the modules area into vmlinux, we
could possibly build modules with -fPIC : this would remove the
restriction on branch range, though there would also be some
performance impact for the modules...

Cheers
---Dave