Re: [regression 4.14rc] 74def747bcd0 (genirq: Restrict effective affinity to interrupts actually using it)
From: Marc Zyngier
Date: Tue Sep 19 2017 - 11:51:15 EST
On 19/09/17 16:40, Yanko Kaneti wrote:
> On Tue, 2017-09-19 at 16:33 +0100, Marc Zyngier wrote:
>> On 19/09/17 16:12, Yanko Kaneti wrote:
>>> Fedora rawhide config here.
>>> AMD FX-8370E
>>> Bisected a problem to:
>>> 74def747bcd0 (genirq: Restrict effective affinity to interrupts actually using it)
>>> It seems to be causing stalls, short lived or long lived lockups very shortly after boot.
>>> Everything becomes jerky.
>>> The only visible in the log indication is something like :
>>> [ 59.802129] clocksource: timekeeping watchdog on CPU3: Marking clocksource 'tsc' as unstable because the skew is too large:
>>> [ 59.802134] clocksource: 'hpet' wd_now: 3326e7aa wd_last: 329956f8 mask: ffffffff
>>> [ 59.802137] clocksource: 'tsc' cs_now: 423662bc6f cs_last: 41dfc91650 mask: ffffffffffffffff
>>> [ 59.802140] tsc: Marking TSC unstable due to clocksource watchdog
>>> [ 59.802158] TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'.
>>> [ 59.802161] sched_clock: Marking unstable (59802142067, 15510)<-(59920871789, -118714277)
>>> [ 60.015604] clocksource: Switched to clocksource hpet
>>> [ 89.015994] INFO: NMI handler (perf_event_nmi_handler) took too long to run: 209.660 msecs
>>> [ 89.016003] perf: interrupt took too long (1638003 > 2500), lowering kernel.perf_event_max_sample_rate to 1000
>>> Just reverting that commit on top of linus mainline cures all the symptoms
>> Interesting. Do you still get HPET interrupts?
> Sorry, I might need some basic help here (i.e where do I count them...)
/proc/interrupts should display them.
> After the watchdog switches the clocksource to hpet the system is still
> somewhat alive, so I'll guess some clock is still ticking....
Probably, but I suspect they're not hitting the right CPU, hence the
Unfortunately, my x86-foo is pretty minimal, and I'm about to drop off
the net for a few days.
Thomas, any insight?
Jazz is not dead. It just smells funny...