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Date: Mon, 29 May 2006 23:36:26 -0500
To: Benjamin Herrenschmidt <benh@au1.ibm.com>
Subject: Re: [PATCH] powerpc: Fix buglet with MMU hash management
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From: Olof Johansson <olof@lixom.net>
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	Paul Mackerras <paulus@samba.org>
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On Tue, May 30, 2006 at 02:14:19PM +1000, Benjamin Herrenschmidt wrote:

> This fixes by allowing the updating of the protection bits in the native
> hash handling to also set (but not clear) the "C" bit, and, in order to
> also improve performances in the general case, by always setting that
> bit on newly inserted hash PTE so that writeback really never happens.

Good catch!

However, you'll have a writeback on the R bit too, you should set that
together with C.


-Olof