Re: [PATCH] cpufreq: flush any pending policy update work scheduled before freeing

From: Rafael J. Wysocki
Date: Mon Oct 21 2019 - 04:20:51 EST


On Mon, Oct 21, 2019 at 4:15 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
>
> On 18-10-19, 12:06, Sudeep Holla wrote:
> > Callstack is:
> >
> > (cpufreq_notifier_max)
> > (notifier_call_chain)
> > (blocking_notifier_call_chain)
> > (pm_qos_update_target)
> > (freq_qos_apply)
> > (freq_qos_remove_request)
> > (cpufreq_policy_free)
> > (subsys_interface_unregister)
> > (cpufreq_unregister_driver)
>
> @sudeep: I see that the patch is merged now, but as I said earlier the
> reasoning isn't clear yet. Please don't stop working on this and lets
> clean this once and for all.
>
> What patches were you testing this with? My buggy patches or Rafael's
> patches as well ? At least with my patches, this can happen due to the
> other bug where the notifier doesn't get removed (as I said earlier),
> but once that bug isn't there then this shouldn't happen, else we have
> another bug in pipeline somewhere and should find it.

Right.

I have found one already which should be fixed in my current
linux-next branch, so testing that in particular would be appreciated.