From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: [PATCH 01/10] PM / OPP: Fix memory leak while adding duplicate OPPs Date: Tue, 6 Dec 2016 17:09:24 -0800 Message-ID: <20161207010924.GF4388@codeaurora.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:33666 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751518AbcLGBSq (ORCPT ); Tue, 6 Dec 2016 20:18:46 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Viresh Kumar Cc: Rafael Wysocki , Viresh Kumar , Nishanth Menon , linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, Vincent Guittot On 12/06, Viresh Kumar wrote: > There are two types of duplicate OPPs that get different behavior from > the core: > A). An earlier OPP is marked 'available' and has same freq/voltages as > the new one. > B). An earlier OPP with same frequency, but is marked 'unavailable' OR > doesn't have same voltages as the new one. > > The OPP core returns 0 for the first one, but -EEXIST for the second. > > While the OPP core returns 0 for the first case, its callers don't free > the newly allocated OPP structure which isn't used anymore. Fix that by > returning -EBUSY instead of 0, but make the callers return 0 eventually. > > As this isn't a critical fix, its not getting marked for stable kernel. > > Signed-off-by: Viresh Kumar Makes sense. > --- > drivers/base/power/opp/core.c | 14 ++++++++++++-- > drivers/base/power/opp/of.c | 6 +++++- > 2 files changed, 17 insertions(+), 3 deletions(-) > > diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c > index a0e6294baf1d..cc69f903fd34 100644 > --- a/drivers/base/power/opp/core.c > +++ b/drivers/base/power/opp/core.c > @@ -1080,6 +1080,12 @@ static bool _opp_supported_by_regulators(struct dev_pm_opp *opp, > return true; > } > > +/* > + * Returns: > + * 0: On success. And appropriate error message for Duplicate OPPs. lowercase duplicate please > + * -EBUSY: For OPP with same freq/volt and is available. > + * -EEXIST: For OPP with same freq but different volt or is unavailable. > + */ > int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, > struct opp_table *opp_table) > { > @@ -1112,7 +1118,7 @@ int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, > > /* Should we compare voltages for all regulators here ? */ > return opp->available && > - new_opp->supplies[0].u_volt == opp->supplies[0].u_volt ? 0 : -EEXIST; > + new_opp->supplies[0].u_volt == opp->supplies[0].u_volt ? -EBUSY : -EEXIST; > } > > new_opp->opp_table = opp_table; > @@ -1186,8 +1192,12 @@ int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt, > new_opp->dynamic = dynamic; > > ret = _opp_add(dev, new_opp, opp_table); > - if (ret) > + if (ret) { > + /* Don't return error for duplicate OPPs */ Yes, but why? > + if (ret == -EBUSY) > + ret = 0; > goto free_opp; > + } > > mutex_unlock(&opp_table_lock); > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project