Subject: Re: Hyper-Threading Vulnerability
From: Lee Revell <rlrevell@joe-job.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Matt Mackall <mpm@selenic.com>, Andy Isaacson <adi@hexapodia.org>,
       Andi Kleen <ak@muc.de>, "Richard F. Rebel" <rrebel@whenu.com>,
       Gabor MICSKO <gmicsko@szintezis.hu>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, tytso@mit.edu
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Date: Fri, 13 May 2005 19:00:12 -0400
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On Fri, 2005-05-13 at 23:47 +0100, Alan Cox wrote:
> On Gwe, 2005-05-13 at 22:59, Matt Mackall wrote:
> > It might not be much of a problem though. If he's a bit off per guess
> > (really impressive), he'll still be many bits off by the time there's
> > enough entropy in the primary pool to reseed the secondary pool so he
> > can check his guesswork.
> 
> You can also disable the tsc to user space in the intel processors.
> Thats something they anticipated as being neccessary in secure
> environments long ago. This makes the attack much harder.

And break the hundreds of apps that depend on rdtsc?  Am I missing
something?

Lee

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