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Subject: Re: kernel panic during kernel module load (powerpc specific part)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Gabriel Paubert <paubert@iram.es>
Date: Wed, 06 Jun 2012 08:14:55 +1000
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Cc: Wrobel Heinz-R39252 <r39252@freescale.com>,
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On Tue, 2012-06-05 at 13:32 +0200, Gabriel Paubert wrote:
> - gcc-4.6 and gcc-4.7 behave identically, if -Os is set, they
>   generate by default lmw/stmw. But if I combine -Os with 
>   -mno-multiple, they call the helper functions.
> 
> In other words, on this system, gcc-4.4 is broken but should not
> cause any harm. gcc-4.6 and gcc-4.7 look correct, but are there
> any processors on which -mno-multiple is worth setting?

It could be an artifact of the -mtune we use, dunno. And yes, I'm pretty
sure some embedded processors don't like multiple load/store.

Cheers,
Ben.