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Date: Tue, 25 May 2004 07:09:37 +0200
From: Andrea Arcangeli <andrea@suse.de>
Subject: Re: [PATCH] ppc64: Fix possible race with set_pte on a present PTE
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To: Linus Torvalds <torvalds@osdl.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>, Andrew Morton <akpm@osdl.org>, Linux Kernel list <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>, Ben LaHaise <bcrl@kvack.org>, linux-mm@kvack.org, Architectures Group <linux-arch@vger.kernel.org>
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> all. However I wonder what happens for PROT_WRITE? How can you make a

I understood now how it works with PROT_WRITE too, it's not FOR but URE
being tweaked together with ACCESSED. This has been a very big misread I
did when I was doing alpha stuff some year ago. that's why I was so
confident it was only setting it during the first page fault and never
clearing it again. Sounds good that it can be emulated fully, I thought
it wasn't even feasible at all.

thanks a lot for pointing out this huge mistake.