Linus, I bet if you force the affinity of your perf record to be on a CPU other than CPU0, you will not get the crash.
This is what I am seeing now. I appears on resume, CPU0 hotplug callbacks for perf_events are not invoked leaving DS_AREA MSR to 0. Can you confirm on your machine? On Fri, Mar 15, 2013 at 12:11 AM, Stephane Eranian <eran...@google.com> wrote: > On Thu, Mar 14, 2013 at 11:53 PM, Stephane Eranian <eran...@google.com> wrote: >> On Thu, Mar 14, 2013 at 11:42 PM, Stephane Eranian <eran...@google.com> >> wrote: >>> On Thu, Mar 14, 2013 at 11:19 PM, Stephane Eranian <eran...@google.com> >>> wrote: >>>> On Thu, Mar 14, 2013 at 11:17 PM, Linus Torvalds >>>> <torva...@linux-foundation.org> wrote: >>>>> On Thu, Mar 14, 2013 at 3:09 PM, Stephane Eranian <eran...@google.com> >>>>> wrote: >>>>>> >>>>>> Could be related to suspend/resume. But were you running perf across >>>>>> that resume/suspend cycle? >>>>> >>>>> No. >>>>> >>>>> In most cases I was running a perf record before and after (but not >>>>> *while* suspending) >>>>> >>>>> In at least one other crash, I didn't run perf before at all, so the >>>>> first time I used perf was after the resume. >>>>> >>>>> So in no cases did I actually have any perf stuff active over the >>>>> suspend itself. >>>>> >>>> Ok, simpler test case then. >>>> >>>>>> Let's see if we can reproduce the problem on the same ChromeBook you >>>>>> have. Don't have one myself. >>>>> >>>>> I don't imagine it should be about chromebook per se, because afaik >>>>> all of pmu suspend/resume is done by the kernel, no firmware involved. >>>>> >>>>> So I'd assume it should happen with any IvyBridge. >>>>> >>>> Will try on a desktop IvyBridge too. >>> >>> Ok, it happens on my IVB desktop too, so I can investigate... >> >> It's not specific to IVB either, it hangs on my Nehalem desktop as well. > > Looks related to PEBS. If I drop the :pp the machine does not hang. Even > a single :p hangs it. So it is possible something is not properly > restored in the > DS state after a resume or is corrupted by the suspend. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
