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Subject: Re: [PATCH] powerpc/8xx: fix regression introduced by cache
	coherency rewrite
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Joakim Tjernlund <joakim.tjernlund@transmode.se>
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Date: Sat, 03 Oct 2009 18:31:18 +1000
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Cc: Scott Wood <scottwood@freescale.com>,
	"linuxppc-dev@ozlabs.org" <linuxppc-dev@ozlabs.org>,
	Rex Feany <RFeany@mrv.com>
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On Sat, 2009-10-03 at 10:05 +0200, Joakim Tjernlund wrote:
> Cannot shake the feeling that it this snip of code that causes it
>         lwz     r11, 0(r10)     /* Get the level 1 entry */
>         rlwinm. r10, r11,0,0,19 /* Extract page descriptor page
> address */
>         beq     2f              /* If zero, don't try to find a pte */
> Perhaps we can do something better? I still feel that we need to
> force a TLB Error as the TLBMiss does not set DSISR so we have no way
> of
> knowing if it is an load or store.

Can't we manufacture a DSISR and branch to the right function ?

Ben.