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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, 17 Jul 2007 17:18:11 +0200
To: David Gibson <david@gibson.dropbear.id.au>
Cc: linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>,
	Arnd Bergmann <arnd@arndb.de>
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>>>> Yeah.  Giving the warning is a good thing though.
>>>
>>> No, it isn't; it's just noise, if we're not ever going to do  
>>> anything
>>> to prevent the behaviour - and we can't.
>>
>> The same userland code will not run correctly on PPC64 or BookE
>> systems.  Is that not a reason to warn?
>
> Way back when, I distinctly recall aborting my plans to implement
> per-page exec on 40x, precisely because of executables like this.

I noticed some comments to that effect in the BookE code,
yes.  It seems userland has been fixed enough that you
could think about enabling it again FWIW.


Segher