Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, Oct 03, 2017 at 07:27:01PM +, Thomas Gleixner wrote: > On Tue, 3 Oct 2017, Thomas Gleixner wrote: > > On Tue, 3 Oct 2017, Thomas Gleixner wrote: > > > On Tue, 3 Oct 2017, Michael Ellerman wrote: > > > > Hmm, I tried that patch, it makes the warning go away. But then I > > > > triggered

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

Thomas Gleixner writes: > On Tue, 3 Oct 2017, Thomas Gleixner wrote: >> On Tue, 3 Oct 2017, Thomas Gleixner wrote: >> > On Tue, 3 Oct 2017, Michael Ellerman wrote: >> > > Hmm, I tried that patch, it makes the warning go away. But then I >> > > triggered a deliberate hard

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017, Thomas Gleixner wrote: > On Tue, 3 Oct 2017, Thomas Gleixner wrote: > > On Tue, 3 Oct 2017, Michael Ellerman wrote: > > > Hmm, I tried that patch, it makes the warning go away. But then I > > > triggered a deliberate hard lockup and got nothing. > > > > > > Then I went back to

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017, Thomas Gleixner wrote: > On Tue, 3 Oct 2017, Michael Ellerman wrote: > > Hmm, I tried that patch, it makes the warning go away. But then I > > triggered a deliberate hard lockup and got nothing. > > > > Then I went back to the existing code (in linux-next), and I still get > >

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017, Michael Ellerman wrote: > Thomas Gleixner writes: > >> The first call is new because previously watchdog_nmi_reconfigure() > >> wasn't called from softlockup_reconfigure_threads(). > > > > Hmm, don't you have the same problem with CPU hotplug or do you just

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

Thomas Gleixner writes: > On Tue, 3 Oct 2017, Michael Ellerman wrote: >> Hi Thomas, >> Unfortunately this is hitting the WARN_ON in start_wd_cpu() on powerpc >> because we're calling it multiple times for the boot CPU. >> >> The first call is via: >> >>

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017, Nicholas Piggin wrote: > On Tue, 3 Oct 2017 09:04:03 +0200 (CEST) > Thomas Gleixner wrote: > > > On Tue, 3 Oct 2017, Thomas Gleixner wrote: > > > On Tue, 3 Oct 2017, Michael Ellerman wrote: > > > > Hi Thomas, > > > > Unfortunately this is hitting the

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017 09:04:03 +0200 (CEST) Thomas Gleixner wrote: > On Tue, 3 Oct 2017, Thomas Gleixner wrote: > > On Tue, 3 Oct 2017, Michael Ellerman wrote: > > > Hi Thomas, > > > Unfortunately this is hitting the WARN_ON in start_wd_cpu() on powerpc > > > because we're

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017, Thomas Gleixner wrote: > On Tue, 3 Oct 2017, Michael Ellerman wrote: > > Hi Thomas, > > Unfortunately this is hitting the WARN_ON in start_wd_cpu() on powerpc > > because we're calling it multiple times for the boot CPU. > > > > The first call is via: > > > >

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

On Tue, 3 Oct 2017, Michael Ellerman wrote: > Hi Thomas, > Unfortunately this is hitting the WARN_ON in start_wd_cpu() on powerpc > because we're calling it multiple times for the boot CPU. > > The first call is via: > > start_wd_on_cpu+0x80/0x2f0 > watchdog_nmi_reconfigure+0x124/0x170 >

Re: [patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

Hi Thomas, Thomas Gleixner writes: > Both the perf reconfiguration and the powerpc watchdog_nmi_reconfigure() > need to be done in two steps. > > 1) Stop all NMIs > 2) Read the new parameters and start NMIs > > Right now watchdog_nmi_reconfigure() is a combination

[patch V2 22/29] lockup_detector: Make watchdog_nmi_reconfigure() two stage

Both the perf reconfiguration and the powerpc watchdog_nmi_reconfigure() need to be done in two steps. 1) Stop all NMIs 2) Read the new parameters and start NMIs Right now watchdog_nmi_reconfigure() is a combination of both. To allow a clean reconfiguration add a 'run' argument and