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Date: Thu, 20 Nov 2008 13:24:38 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Takashi Iwai <tiwai@suse.de>
CC: Arjan van de Ven <arjan@infradead.org>, linux-kernel@vger.kernel.org,
       Luc Verhaegen <lverhaegen@suse.de>, Egbert Eich <eich@suse.de>
Subject: Re: vm86 segfaults with NX bit
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Takashi Iwai wrote:
>>>>
>>> did the code that mapped this memory setup use PROT_EXEC ?
>> A good question...
>> Luc, Egbert, how does VESA driver handle it?
> 
> Just looking through the vesa directory of xorg-server code, PROT_EXEC
> is passed for all mappings, at least.
> 
> Please correct me if I'm looking at a wrong place...
> 

Please do an strace of the X server startup up to the point of the crash.

I am betting that PROT_EXEC is missing from an mmap(), or that it needs 
an additional mprotect().

	-hpa