Added some CC-s because of bisect find. Whole context should be still here.
> > > > > > This is on my trusty IBM PC365, dual Pentium Pro. 4.10 worked fine, > > > > > > 4.10.0-09686-g9e314890292c and 4.10.0-10770-g2d6be4abf514 exhibit a > > > > > > problem. Ocassionally NMI watchdog kicks in and discovers one of > > > > > > the > > > > > > CPUs in LOCKUP. The system keeps running fine. The first lockup was > > > > > > different, all the others were from arch_cpu_idle. Sometime ecey > > > > > > couple > > > > > > of seconds (after some activity), sometimes nothing for a long time > > > > > > (idle, no SSH logins). > > > > > > > > > > The only watchdog related patch which hit after 4.10 is: > > > > > > > > > > 8dcde9def5a1 kernel/watchdog.c: do not hardcode CPU 0 as the initial > > > > > thread > > > > > > > > > > Can you try to revert that for a start? I'm not seeing why it should > > > > > be the > > > > > culprit from a quick glance, but ... > > > > > > > > Reverting this patch does not help. > > > > > > I did not expect that, but excluding it was a valid shot in the > > > dark. Thanmks for trying. > > > > > > To be honest, I have no idea what causes that at the moment, but I will > > > come back to you tomorrow after thinking it through (with brain awake) how > > > to debug this. > > > > Went through the related changes which came in during the merge window. One > > which affects the per cpu timers is: 914122c389d0 > > > > Can you try to revert that one please? > > Running out of obvious culprits. Any chance that you can do a bisect or > this too painful on that box? Done on a P4 where the problem also appeared. The bisecting resulted in this commit. Does it seem realistic? I will also try if this help son the old PPro. 93825f2ec736f30e034ab7c9d56b42849c5b00da is the first bad commit commit 93825f2ec736f30e034ab7c9d56b42849c5b00da Author: Frederic Weisbecker <[email protected]> Date: Tue Jan 31 04:09:16 2017 +0100 jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY NSEC_PER_JIFFY is an ad-hoc redefinition of TICK_NSEC. Let's rather use a unique and well maintained version. Signed-off-by: Frederic Weisbecker <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Tony Luck <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Stanislaw Gruszka <[email protected]> Cc: Wanpeng Li <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> :040000 040000 219afc6bb9e757532791f93ed05ddf68a7124cb0 fb9cc12366f970c1bc4872cc38b1c4df5ce9594d M kernel -- Meelis Roos ([email protected])
