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From: Mike Frysinger <vapier.adi@gmail.com>
Date: Wed, 15 Jul 2009 07:12:20 -0400
Message-ID: <8bd0f97a0907150412h234cf4d6l439d92d832055373@mail.gmail.com>
Subject: Re: [Uclinux-dist-devel] [PATCH v2] NOMMU: add support for Memory 
	Protection Units (MPU)
To: David Howells <dhowells@redhat.com>
Cc: Bernd Schmidt <bernds_cb1@t-online.de>,
       uclinux-dist-devel@blackfin.uclinux.org, linux-kernel@vger.kernel.org
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On Wed, Jul 15, 2009 at 06:37, David Howells wrote:
> Bernd Schmidt <bernds_cb1@t-online.de> wrote:
>> No page table, just three bitmaps (r/w/x), with one bit per page, per mm.
>
> I presume that all you do is maintain a distinction between
> userspace-accessible areas and kernel-only areas, and don't prevent userspace
> processes from destroying each other.

there is full 4k page protection between processes and between the
kernel and processes.
-mike
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