Re: [PATCH] opp: of: drop incorrect lockdep_assert_held()

From: Viresh Kumar
Date: Wed Oct 23 2019 - 22:56:52 EST


On 23-10-19, 14:01, Niklas Cassel wrote:
> On Wed, Oct 23, 2019 at 11:00:05AM +0530, Viresh Kumar wrote:
> > On 10-10-19, 16:00, Viresh Kumar wrote:
> > > _find_opp_of_np() doesn't traverse the list of OPP tables but instead
> > > just the entries within an OPP table and so only requires to lock the
> > > OPP table itself.
> > >
> > > The lockdep_assert_held() was added there by mistake and isn't really
> > > required.
> > >
> > > Fixes: 5d6d106fa455 ("OPP: Populate required opp tables from "required-opps" property")
> > > Cc: v5.0+ <stable@xxxxxxxxxxxxxxx> # v5.0+
> > > Reported-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
> > > Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> > > ---
> > > drivers/opp/of.c | 2 --
> > > 1 file changed, 2 deletions(-)
> > >
> > > diff --git a/drivers/opp/of.c b/drivers/opp/of.c
> > > index 1813f5ad5fa2..6dc41faf74b5 100644
> > > --- a/drivers/opp/of.c
> > > +++ b/drivers/opp/of.c
> > > @@ -77,8 +77,6 @@ static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
> > > {
> > > struct dev_pm_opp *opp;
> > >
> > > - lockdep_assert_held(&opp_table_lock);
> > > -
> > > mutex_lock(&opp_table->lock);
> > >
> > > list_for_each_entry(opp, &opp_table->opp_list, node) {
> >
> > @Niklas, any inputs from your side here would be appreciated :)
>
> Tested-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
>
> After this patch, there is still a single lockdep_assert_held()
> left, inside _find_table_of_opp_np(), since you kept this,
> I assume that that one is still needed?

Yeah, that one is required as we are traversing the list of OPP tables
there.

--
viresh