Re: Hyper-Threading Vulnerability

Andi Kleen
2005-05-13T19:16:01Z

On Fri, May 13, 2005 at 02:38:03PM -0400, Richard F. Rebel wrote:
> On Fri, 2005-05-13 at 20:03 +0200, Andi Kleen wrote:
> > This is not a kernel problem, but a user space problem. The fix
> > is to change the user space crypto code to need the same number of cache line
> > accesses on all keys.
> >
> > Disabling HT for this would the totally wrong approach, like throwing
> > out the baby with the bath water.
> >
> > -Andi
>
> Why? It's certainly reasonable to disable it for the time being and
> even prudent to do so.

No, i strongly disagree on that. The reasonable thing to do is
to fix the crypto code which has this vulnerability, not break
a useful performance enhancement for everybody else.

-Andi