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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH] Allow exec on 32-bit from readable, non-exec pages,
	with a warning.
Date: Tue, 10 Jul 2007 15:08:53 +0200
To: Scott Wood <scottwood@freescale.com>
Cc: linuxppc-dev@ozlabs.org, paulus@samba.org, Arnd Bergmann <arnd@arndb.de>
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>> 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;

Not on a per-page basis, anyway.

> otherwise, it'd never have worked in the first place.  Note that  
> this is
> only allowed on 32-bit, non-book-E.
>
> There isn't much value in enforcing non-exec mappings only if it  
> happens
> to be the first fault on a given page.

Yeah.  Giving the warning is a good thing though.


Segher