From patchwork Wed Aug 17 15:14:59 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brendan Jackman X-Patchwork-Id: 9286075 X-Patchwork-Delegate: rui.zhang@intel.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7960B60839 for ; Wed, 17 Aug 2016 15:15:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 67D5329554 for ; Wed, 17 Aug 2016 15:15:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5C00C29560; Wed, 17 Aug 2016 15:15:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2B4A229554 for ; Wed, 17 Aug 2016 15:15:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752569AbcHQPPQ (ORCPT ); Wed, 17 Aug 2016 11:15:16 -0400 Received: from foss.arm.com ([217.140.101.70]:53472 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752508AbcHQPPP (ORCPT ); Wed, 17 Aug 2016 11:15:15 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B54D143F; Wed, 17 Aug 2016 08:16:48 -0700 (PDT) Received: from brendan-thinkstation.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1079C3F21A; Wed, 17 Aug 2016 08:15:13 -0700 (PDT) From: Brendan Jackman To: linux-pm@vger.kernel.org Cc: Amit Daniel Kachhap , Viresh Kumar , Javi Merino Subject: [PATCH] thermal: cpu_cooling: Fix NULL dereference in cpufreq_state2power Date: Wed, 17 Aug 2016 16:14:59 +0100 Message-Id: <20160817151459.10948-1-brendan.jackman@arm.com> X-Mailer: git-send-email 2.9.2 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently all CPU cooling devices share a `struct thermal_cooling_device_ops` instance. The thermal core uses the presence of functions in this struct to determine if a cooling device has a power model (see cdev_is_power_actor). cpu_cooling.c adds the power model functions to the shared struct when a device is registered with a power model. Therefore, if a CPU cooling device is registered using [of_]cpufreq_power_cooling_register, _all_ devices will be determined to have a power model, including any registered with [of_]cpufreq_cooling_register. This can result in cpufreq_state2power being called on a device where dyn_power_table is NULL. With this commit, instead of having a shared thermal_cooling_device_ops which is mutated, we have two versions: one with the power functions and one without. Signed-off-by: Brendan Jackman Cc: Amit Daniel Kachhap Cc: Viresh Kumar Cc: Javi Merino Acked-by: Viresh Kumar Acked-by: Javi Merino --- drivers/thermal/cpu_cooling.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) -- 2.9.2 -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c index 3788ed7..a32b417 100644 --- a/drivers/thermal/cpu_cooling.c +++ b/drivers/thermal/cpu_cooling.c @@ -740,12 +740,22 @@ static int cpufreq_power2state(struct thermal_cooling_device *cdev, } /* Bind cpufreq callbacks to thermal cooling device ops */ + static struct thermal_cooling_device_ops cpufreq_cooling_ops = { .get_max_state = cpufreq_get_max_state, .get_cur_state = cpufreq_get_cur_state, .set_cur_state = cpufreq_set_cur_state, }; +static struct thermal_cooling_device_ops cpufreq_power_cooling_ops = { + .get_max_state = cpufreq_get_max_state, + .get_cur_state = cpufreq_get_cur_state, + .set_cur_state = cpufreq_set_cur_state, + .get_requested_power = cpufreq_get_requested_power, + .state2power = cpufreq_state2power, + .power2state = cpufreq_power2state, +}; + /* Notifier for cpufreq policy change */ static struct notifier_block thermal_cpufreq_notifier_block = { .notifier_call = cpufreq_thermal_notifier, @@ -795,6 +805,7 @@ __cpufreq_cooling_register(struct device_node *np, struct cpumask temp_mask; unsigned int freq, i, num_cpus; int ret; + struct thermal_cooling_device_ops *cooling_ops; cpumask_and(&temp_mask, clip_cpus, cpu_online_mask); policy = cpufreq_cpu_get(cpumask_first(&temp_mask)); @@ -850,10 +861,6 @@ __cpufreq_cooling_register(struct device_node *np, cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus); if (capacitance) { - cpufreq_cooling_ops.get_requested_power = - cpufreq_get_requested_power; - cpufreq_cooling_ops.state2power = cpufreq_state2power; - cpufreq_cooling_ops.power2state = cpufreq_power2state; cpufreq_dev->plat_get_static_power = plat_static_func; ret = build_dyn_power_table(cpufreq_dev, capacitance); @@ -861,6 +868,10 @@ __cpufreq_cooling_register(struct device_node *np, cool_dev = ERR_PTR(ret); goto free_table; } + + cooling_ops = &cpufreq_power_cooling_ops; + } else { + cooling_ops = &cpufreq_cooling_ops; } ret = get_idr(&cpufreq_idr, &cpufreq_dev->id); @@ -885,7 +896,7 @@ __cpufreq_cooling_register(struct device_node *np, cpufreq_dev->id); cool_dev = thermal_of_cooling_device_register(np, dev_name, cpufreq_dev, - &cpufreq_cooling_ops); + cooling_ops); if (IS_ERR(cool_dev)) goto remove_idr;