From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FB58C4332F for ; Fri, 25 Mar 2022 09:02:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356118AbiCYJDg (ORCPT ); Fri, 25 Mar 2022 05:03:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56924 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229940AbiCYJDd (ORCPT ); Fri, 25 Mar 2022 05:03:33 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id CA428CD332; Fri, 25 Mar 2022 02:01:59 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7090412FC; Fri, 25 Mar 2022 02:01:59 -0700 (PDT) Received: from [10.57.22.201] (unknown [10.57.22.201]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B77173F66F; Fri, 25 Mar 2022 02:01:57 -0700 (PDT) Message-ID: Date: Fri, 25 Mar 2022 09:01:55 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH v2] thermal: devfreq_cooling: use local ops instead of global ops Content-Language: en-US To: Kant Fan Cc: amitk@kernel.org, rui.zhang@intel.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, allwinner-opensource-support@allwinnertech.com, stable@vger.kernel.org, rafael@kernel.org, daniel.lezcano@linaro.org, ionela.voinescu@arm.com References: <20220325073030.91919-1-kant@allwinnertech.com> From: Lukasz Luba In-Reply-To: <20220325073030.91919-1-kant@allwinnertech.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kant, On 3/25/22 07:30, Kant Fan wrote: > Fix access illegal address problem in following condition: > There are muti devfreq cooling devices in system, some of them has > em model but other does not, energy model ops such as state2power will > append to global devfreq_cooling_ops when the cooling device with > em model register. It makes the cooling device without em model > also use devfreq_cooling_ops after appending when register later by > of_devfreq_cooling_register_power() or of_devfreq_cooling_register(). > > IPA governor regards the cooling devices without em model as a power actor > because they also have energy model ops, and will access illegal address > at dfc->em_pd when execute cdev->ops->get_requested_power, > cdev->ops->state2power or cdev->ops->power2state. > > Fixes: 615510fe13bd2 ("thermal: devfreq_cooling: remove old power model and use EM") > Cc: stable@vger.kernel.org # 5.13+ > Signed-off-by: Kant Fan > --- > drivers/thermal/devfreq_cooling.c | 25 ++++++++++++++++++------- > 1 file changed, 18 insertions(+), 7 deletions(-) > > diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c > index 4310cb342a9f..d38a80adec73 100644 > --- a/drivers/thermal/devfreq_cooling.c > +++ b/drivers/thermal/devfreq_cooling.c > @@ -358,21 +358,28 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, > struct thermal_cooling_device *cdev; > struct device *dev = df->dev.parent; > struct devfreq_cooling_device *dfc; > + struct thermal_cooling_device_ops *ops; > char *name; > int err, num_opps; > > - dfc = kzalloc(sizeof(*dfc), GFP_KERNEL); > - if (!dfc) > + ops = kmemdup(&devfreq_cooling_ops, sizeof(*ops), GFP_KERNEL); > + if (!ops) > return ERR_PTR(-ENOMEM); > > + dfc = kzalloc(sizeof(*dfc), GFP_KERNEL); > + if (!dfc) { > + err = -ENOMEM; > + goto free_ops; > + } > + > dfc->devfreq = df; > > dfc->em_pd = em_pd_get(dev); > if (dfc->em_pd) { > - devfreq_cooling_ops.get_requested_power = > + ops->get_requested_power = > devfreq_cooling_get_requested_power; > - devfreq_cooling_ops.state2power = devfreq_cooling_state2power; > - devfreq_cooling_ops.power2state = devfreq_cooling_power2state; > + ops->state2power = devfreq_cooling_state2power; > + ops->power2state = devfreq_cooling_power2state; > > dfc->power_ops = dfc_power; > > @@ -407,8 +414,7 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, > if (!name) > goto remove_qos_req; > > - cdev = thermal_of_cooling_device_register(np, name, dfc, > - &devfreq_cooling_ops); > + cdev = thermal_of_cooling_device_register(np, name, dfc, ops); > kfree(name); > > if (IS_ERR(cdev)) { > @@ -429,6 +435,8 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, > kfree(dfc->freq_table); > free_dfc: > kfree(dfc); > +free_ops: > + kfree(ops); > > return ERR_PTR(err); > } > @@ -510,11 +518,13 @@ EXPORT_SYMBOL_GPL(devfreq_cooling_em_register); > void devfreq_cooling_unregister(struct thermal_cooling_device *cdev) > { > struct devfreq_cooling_device *dfc; > + const struct thermal_cooling_device_ops *ops; > struct device *dev; > > if (IS_ERR_OR_NULL(cdev)) > return; > > + ops = cdev->ops; > dfc = cdev->devdata; > dev = dfc->devfreq->dev.parent; > > @@ -525,5 +535,6 @@ void devfreq_cooling_unregister(struct thermal_cooling_device *cdev) > > kfree(dfc->freq_table); > kfree(dfc); > + kfree(ops); > } > EXPORT_SYMBOL_GPL(devfreq_cooling_unregister); Thank you for updating it, LGTM Reviewed-by: Lukasz Luba Regards, Lukasz