Re: [PATCH] Blacklist Dell Optiplex 320 from using the HPET

Andi Kleen
2007-05-04T23:22:12Z

On Friday 04 May 2007 23:44:08 Andrew Morton wrote:
> On Fri, 04 May 2007 14:29:04 -0700
> john stultz <johnstul@us.ibm.com> wrote:
>
> > One of the 2.6.21 regressions was Guilherme's problem seeing his box
> > lock up when the system detected an unstable TSC and dropped back to
> > using the HPET.
> >
> > In digging deeper, we found the HPET is not actually incrementing on
> > this system. And in fact, the reason why this issue just cropped up was
> > because of Thomas's clocksource watchdog code was comparing the TSC to
> > the HPET (which wasn't moving) and thought the TSC was broken.
> >
> > Anyway, Guliherme checked for a BIOS update and did not find one, so
> > I've added a DMI blacklist against his system so the HPET is not used.
> >
> > Many thanks to Guilherme for the slow and laborious testing that finally
> > narrowed down this issue.
> >
>
> OK, I tagged that for -stable too.

Don't please. It is completely the wrong approach. DMI should be only last resort,
not first.

-Andi