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Date: Mon, 12 Jul 2004 21:48:42 -0700
From: Andrew Morton <akpm@osdl.org>
To: Hugh Dickins <hugh@veritas.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rmaplock 1/6 PageAnon in mapping
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Hugh Dickins <hugh@veritas.com> wrote:
>
> Replace the PG_anon page->flags bit by setting the lower bit of the
>  pointer in page->mapping when it's anon_vma: PAGE_MAPPING_ANON bit.

This is likely to cause conniptions in various quarters.  Is there no
alternative?

It might make things more palatable to hide the setting, clearing testing
amd masking of this bit behind some set of wrapper functions.  Maybe.