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From: Ulrich Weigand <weigand@immd1.informatik.uni-erlangen.de>
Message-Id: <200211122132.WAA03038@faui11.informatik.uni-erlangen.de>
Subject: Re: [PATCH] flush_cache_page while pte valid
To: manfred@colorfullife.com
Date: Tue, 12 Nov 2002 22:32:03 +0100 (MET)
Cc: linux-kernel@vger.kernel.org, uweigand@de.ibm.com
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Manfred Spraul wrote:

>The assumption for the dirty bit is that the i386 cpu are the only cpus 
>in the world (TM) that maintain the dirty bit in hardware

Not true; the s390 also has a dirty bit in hardware ;-)

To make things more interesting, the s390 dirty bit does not
reside in the pte, but in a storage key associated with the
*physical* page.  The bit is set on any access to the physical
page, whether through any virtual mapping, by direct access
with dynamic address translation switched off, or by an I/O
device moving data directly to main memory.

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  weigand@informatik.uni-erlangen.de
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