Re: Hyper-Threading Vulnerability

Barry K. Nathan
2005-05-13T20:34:43Z

On Fri, May 13, 2005 at 03:14:43PM -0400, Jim Crilly wrote:
> And what if you have more than one physical HT processor? AFAIK there's no
> way to disable HT and still run SMP at the same time.

Actually, there is; read my post earlier in this thread:
http://marc.theaimsgroup.com/?l=linux-kernel&m=111598859708620&w=2

To elaborate on the "check dmesg" part of that e-mail:

After you reboot with "maxcpus=2" (or however many physical CPU's you
have), you need to make sure you have messages like this, which indicate
that it really worked:

WARNING: No sibling found for CPU 0.
WARNING: No sibling found for CPU 1.

(and so on, if you have more than 2 CPU's)

-Barry K. Nathan <barryn@pobox.com>