Messages in this thread | | | Date | Wed, 10 Nov 2010 00:21:53 +0000 | From | Alan Cox <> | Subject | Re: [Security] [PATCH v3 0/4] x86: clear XD_DISABLED flag on Intel to regain NX |
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> Only Intel has this problem (it's the only CPU that defines this MSR), so > that'll reduce it. But Google is of no help to me on this; where can I find > these documents?
www.intel.com 8)
> > I'm not specifically aware of any but I do know for example that there > > are other CPU BIOS disablable features that some systems disable in the > > BIOS for good reason (an ancient example being the original Pentium > > REP MOVS optimisation on some steppings) > > By definition there should be fewer errata CPUs than those than need their > BIOS ignored, so I still think this patch makes sense (especially since it > can trivially be worked around with the noexec=off boot option).
We need to be sure because the last thing you want is even 1% of your 10% of users to sudden get magical random memory corruption from overriding something wrongly !
It's definitely worth checking and worth doing because even if there is one (and I have no idea if there is) it'll tell you which steppings
Alan
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