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Date: Wed, 11 Apr 2007 11:56:05 +0900
From: Akinobu Mita <mita@fixstars.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [patch 3/3] cell: prevent alignment interrupt on local store
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Cc: Arnd Bergmann <arnd@arndb.de>, linuxppc-dev@ozlabs.org,
	Paul Mackerras <paulus@samba.org>, cbe-oss-dev@ozlabs.org
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On Wed, Apr 11, 2007 at 07:22:48AM +1000, Benjamin Herrenschmidt wrote:
> On Tue, 2007-04-10 at 20:15 +0900, Akinobu Mita wrote:
> > An Alignment interrupt occurs when the instruction is lmw, stmw, lswi, lswx,
> > stswi, or stswx, and the operand is in local store.
> > 
> > GCC generated such instructions to handle memcpy() instead of kernel
> > defined memcpy() without -mno-string option.
> > 
> > Signed-off-by: Akinobu Mita <mita@fixstars.com>
> 
> I would personally prefer building the entire kernel with -mno-string
> when cell support is enabled...

I'm about to resend the patch which prevent alignment interrupts on LS
by using memcpy_fromio() rather than putting a collection of -mno-* options
in Makefile. (only -mno-string is not enough to prevent that as Segher said)