2009-07-29 14:08:44

by Aaron Gray

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Subject: Does Linux support Data Exectiion Protection ?

Does Linux suppoert DEP, on newer x86 CPU's ?

I am wondering as this does effect alot of VM's using JIT technology if they
are wriiten without proper code memory allocation. This is a problem for
StrongTalk and FoNC' IDC. If EP is availiable how configurable is it ?

Many thanks in advance,

Aaron


2009-07-29 14:34:36

by Arjan van de Ven

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Subject: Re: Does Linux support Data Exectiion Protection ?

On Wed, 29 Jul 2009 15:08:35 +0100
"Aaron Gray" <[email protected]> wrote:

> Does Linux suppoert DEP, on newer x86 CPU's ?

it does and has been for the better part of at least 5 years.


> I am wondering as this does effect alot of VM's using JIT technology
> if they are wriiten without proper code memory allocation.

given how old our support is, all JITs seem to be working.
In addition there is a compatibility provision for legacy binaries
implemented.

> This is a
> problem for StrongTalk and FoNC' IDC. If EP is availiable how
> configurable is it ?

just make sure you use 64 bit pagetables (either a 64 bit kernel or a
32 bit kernel with PAE support) and you get the support.


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Arjan van de Ven Intel Open Source Technology Centre
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