linux-kernel - vm86 segfaults with NX bit

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Date:	Thu, 20 Nov 2008 16:39:06 +0100
From:	Takashi Iwai <tiwai@...e.de>
To:	linux-kernel@...r.kernel.org
Subject: vm86 segfaults with NX bit

Hi,

X guys reported that VESA driver segfaults in vm86 mode with a kernel
with CONFIG_X86_PAE, and it turned to be the NX bit.  See Novell
bugzilla #443440:
	https://bugzilla.novell.com/show_bug.cgi?id=443440

I can confirm that the latest 2.6.28-rc still causes the same problem,
and it disappears when booted with noexec=off option.

Also, when NX bit is reset for the first 1MB (or smaller) in
do_sys_vm86(), it also works as expected.  But I have little clue
where to restore the bit again.

Any good suggestions / solutions?

thanks,

Takashi
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