Re: PPro arch_cpu_idle: NMI watchdog: Watchdog detected hard LOCKUP on cpu 1

From: Thomas Gleixner
Date: Wed Mar 01 2017 - 12:07:34 EST


On Wed, 1 Mar 2017, Meelis Roos wrote:

> 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 ...

Thanks,

tglx