hi, Thomas Gleixner,

On Tue, Jul 29, 2025 at 09:27:56AM +0200, Thomas Gleixner wrote:
> Oliver!
> 
> On Tue, Jul 29 2025 at 08:22, Oliver Sang wrote:
> > On Fri, Jul 25, 2025 at 05:45:04PM +0200, Thomas Gleixner wrote:
> >> Can you please enable CONFIG_PREEMPT_TRACER and add
> >> 
> >> 'trace_event=preemptirq:preempt_disable,preemptirq:preempt_enable ftrace_dump_on_oops'
> >> 
> >> to the kernel command line. The latter will dump the recorded
> >> preempt_enable/disable events and we can pinpoint the function which is
> >> responsible for that.
> >
> > the config with CONFIG_PREEMPT_TRACER enabled is attached as
> > config-6.16.0-rc5-00002-g56180dd20c19
> >
> > by this config, we still see random
> > WARNING:at_kernel/sched/core.c:#preempt_count_sub
> ...
> > but bot seems not be able to capture other new dmesg stats.
> 
> Ah. The tracer does not dump on warnings by default. You need
> 'panic_on_warn' on the command line as well. Forgot about that earlier.

attached one dmesg FYI.

> 
> Thanks,
> 
>         tglx
>