Re: [PATCH -v3] perf, x86: try to handle unknown nmis with runningperfctrs

From: Ingo Molnar
Date: Wed Aug 25 2010 - 06:42:09 EST



* Robert Richter <robert.richter@xxxxxxx> wrote:

> On 20.08.10 11:25:10, Ingo Molnar wrote:
>
> > > Ingo Molnar <mingo@xxxxxxx> wrote:
> > >
> > > >
> > > >it's not working so well, i'm getting:
> > > >
> > > > Uhhuh. NMI received for unknown reason 00 on CPU 9.
> > > > Do you have a strange power saving mode enabled?
> > > > Dazed and confused, but trying to continue
> > > >
> > > >on a nehalem box, after a perf top and perf stat run.
> >
> > FYI, it does not trigger on an AMD box.
>
> Ingo,
>
> do you mean it does not trigger false positives on AMD? [...]

Correct, on AMD boxes i do not get this message during the first 'perf
top' run:

> > > > Uhhuh. NMI received for unknown reason 00 on CPU 9.
> > > > Do you have a strange power saving mode enabled?
> > > > Dazed and confused, but trying to continue

Before the two patches i did not get these messages at all, on any of
the systems.

> You might use the debug patch below for diagnostics.

Thanks, will try that and report back.

Ingo
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