Re: [PATCH] cpufreq: scpi/scmi: Fix freeing of dynamic OPPs

[Rafael J. Wysocki]

On Friday, January 4, 2019 12:01:42 PM CET Sudeep Holla wrote:
> On Fri, Jan 04, 2019 at 03:14:33PM +0530, Viresh Kumar wrote:
> > Since the commit 2a4eb7358aba ("OPP: Don't remove dynamic OPPs from
> > _dev_pm_opp_remove_table()"), dynamically created OPP aren't
> > automatically removed anymore by dev_pm_opp_cpumask_remove_table(). This
> > affects the scpi and scmi cpufreq drivers which no longer free OPPs on
> > failures or on invocations of the policy->exit() callback.
> >
> > Create a generic OPP helper dev_pm_opp_remove_all_dynamic() which can be
> > called from these drivers instead of dev_pm_opp_cpumask_remove_table().
> >
> > In dev_pm_opp_remove_all_dynamic(), we need to make sure that the
> > opp_list isn't getting accessed simultaneously from other parts of the
> > OPP core while the helper is freeing dynamic OPPs, i.e. we can't drop
> > the opp_table->lock while traversing through the OPP list. And to
> > accomplish that, this patch also creates _opp_kref_release_unlocked()
> > which can be called from this new helper with the opp_table lock already
> > held.
> >
> 
> I did test it but since I couldn't reproduce the original issue, my
> tested-by is not that worth. Anyways the changes look fine to me.
> 
> Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>

Applied and pushed to Linus, thanks!