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Date: Mon, 09 Jul 2007 16:32:34 -0500
From: Scott Wood <scottwood@freescale.com>
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To: Scott Wood <scottwood@freescale.com>
Subject: Re: [PATCH] Allow exec on 32-bit from readable, non-exec pages, with
	a warning.
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Cc: linuxppc-dev@ozlabs.org, paulus@samba.org, Arnd Bergmann <arnd@arndb.de>
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Scott Wood wrote:
> Arnd Bergmann wrote:
>> I may be missing the obvious, but doesn't that defeat the purpose of
>> non-executable mappings?
> 
> 
> The hardware in question doesn't support non-executable mappings; 
> otherwise, it'd never have worked in the first place.  Note that this is 
> only allowed on 32-bit, non-book-E.

To be more precise, the classic MMU does appear to have non-exec 
functionality, but at the segment level, which is less than useful for 
implementing vma flags.

-Scott