On Fri, May 09, 2014 at 12:19:49PM -0400, Vince Weaver wrote: > On Thu, 8 May 2014, Cyrill Gorcunov wrote: > > > > Updated. > > --- > > arch/x86/kernel/cpu/perf_event_p4.c | 67 > > ++++++++++++++++-------------------- > > 1 file changed, 30 insertions(+), 37 deletions(-) > > I tried this patch, and even though it seemed to fix one of the NMI storms > I was experiencing I've managed to trigger again using a different random > seed.
Thanks a lot for help in testing, Vince! I think the patch would be still needed so I will prepare normal change log explaining what has been fixed in the patch. > I've been trying to track down a trace of what is triggering things, but > this is very difficult as the full log isn't making it to the serial > console, even when I fsync() stdout. I see. Need to think. Maybe something comes to mind. Debuggin it is really a hard job :/ I've been promised to get access to real p4 machine next week, maybe I find something. > Maybe related, but the following messages tend to happen a lot while > fuzzing, and always happen before the fuzzing that eventually locks up: > > The warnings are for > if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED))) > and > WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED); Thanks for info, Vince! Look, every time you start perf_fuzzer (note, I didn't read its code yet, that's why I'm asking) -- does it log which events are passed to kernel from userspace? Btw, do you run kernel with nmi-watchdog turned on? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
