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Date: Tue, 27 Mar 2007 03:20:33 -0400
From: "Mike Frysinger" <vapier.adi@gmail.com>
To: "Pekka J Enberg" <penberg@cs.helsinki.fi>
Subject: Re: [PATCH -mm] Revoke core code: fix nommu arch compiling error bug
Cc: "Wu, Bryan" <bryan.wu@analog.com>, "David Howells" <dhowells@redhat.com>,
       "Andrew Morton" <akpm@linux-foundation.org>,
       linux-kernel@vger.kernel.org, "Hugh Dickins" <hugh@veritas.com>,
       "Alan Cox" <alan@lxorguk.ukuu.org.uk>
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On 3/27/07, Pekka J Enberg <penberg@cs.helsinki.fi> wrote:
> On Tue, 27 Mar 2007, Wu, Bryan wrote:
> > Agree. MPU of Blackfin can provide some processes protection. But maybe
> > at this moment just disable revoke for NOMMU is easier for further
> > development. When we provide the MPU stuff, maybe we can enable the
> > revoke for NOMMU but MPU arch.
>
> Yeah, MPU should be sufficient for revoke(). Note that mmap() and mummap()
> suffers from the same problem on NOMMU so perhaps we really should do
> CONFIG_MPU.

we would need both ... MPU gives us the ability to restrict access,
but we'd still be unable to do fun things like COW
-mike