On Wed, 21 Jun 2017, Thomas Gleixner wrote: > On Wed, 21 Jun 2017, kan.liang@xxxxxxxxx wrote: > > We now have more and more systems where the Turbo range is wide enough > > that the NMI watchdog expires faster than the soft watchdog timer that > > updates the interrupt tick the NMI watchdog relies on. > > > > This problem was originally added by commit 58687acba592 > > ("lockup_detector: Combine nmi_watchdog and softlockup detector"). > > Previously the NMI watchdog would always check jiffies, which were > > ticking fast enough. But now the backing is quite slow so the expire > > time becomes more sensitive. > > And slapping a factor 3 on the NMI period is the wrong answer to the > problem. The simple solution would be to increase the hrtimer frequency, > but that's not really desired either. Thinking a bit more about it. Increasing the hrtimer frequency and maintaining the current frequency of softlockup_watchdog wakeups, would be probably the most trivial workaround for now. Thanks, tglx