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Date: Tue, 25 May 2004 14:54:20 -0700 (PDT)
From: Linus Torvalds <torvalds@osdl.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cc: "David S. Miller" <davem@redhat.com>, wesolows@foobazco.org,
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Subject: Re: [PATCH] ppc64: Fix possible race with set_pte on a present PTE
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On Wed, 26 May 2004, Benjamin Herrenschmidt wrote:
> 
> Well, just setting one of those 2 bits doesn't require a hash table
> invalidate as long as nothing else changes.

Ok. And nothing ever writes to the SW page tables outside the page table 
lock, right? So on ppc64, we could just do

	#define ptep_update_dirty_accessed(ptep, entry, dirty) \
		*(ptep) = (entry)

and be done with it. No?

I'm not going to do it without a big ack from you.

		Linus