Re: vm86 segfaults with NX bit

From: Arjan van de Ven
Date: Thu Nov 20 2008 - 11:58:10 EST


On Thu, 20 Nov 2008 16:39:06 +0100
Takashi Iwai <tiwai@xxxxxxx> wrote:

> 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?
>

did the code that mapped this memory setup use PROT_EXEC ?


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Arjan van de Ven Intel Open Source Technology Centre
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