Re: [PATCH 3/5] perf, x86: Disable PEBS on clowertown chips

Peter Zijlstra
2010-03-05T21:05:40Z

On Fri, 2010-03-05 at 20:15 +0100, Peter Zijlstra wrote:
> On Fri, 2010-03-05 at 10:58 -0800, Stephane Eranian wrote:
> > > case 15: /* original 65 nm celeron/pentium/core2/xeon, "Merom"/"Conroe" */
> > > + x86_pmu.quirks = intel_clowertown_quirks;
> >
> > That's too coarse grain!
> > It is more subtle than this. Some of the errata are marked as Plan
> > fix. They seem to be
> > fixed in later models. Your looking at the E5xxx series errata but the
> > E7xxx do not have
> > the same problems.
>
> OK, I'll look at those errata again and try to come up with a stepping
> test for this errata.

The two serious ones, AJ106 and AJ68 are no fix and are listed as such
in all errata I can find, including the 7[23]00 series.

I checked the 65nm Core2Duo, Xeon 5200 and Xeon 7[23]00 spec updates.
Going by that it seems the full model 15 family is broken and I'll leave
the patch as is.