From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Aaron Plattner , "Rafael J. Wysocki" Subject: [PATCH 3.15 55/66] cpufreq: unlock when failing cpufreq_update_policy() Date: Fri, 4 Jul 2014 15:14:54 -0700 Message-Id: <20140704221425.319308546@linuxfoundation.org> In-Reply-To: <20140704221422.813435485@linuxfoundation.org> References: <20140704221422.813435485@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aaron Plattner commit fefa8ff810c5ab4c4206aed9d159c4d6fe8d4f1c upstream. Commit bd0fa9bb455d introduced a failure path to cpufreq_update_policy() if cpufreq_driver->get(cpu) returns NULL. However, it jumps to the 'no_policy' label, which exits without unlocking any of the locks the function acquired earlier. This causes later calls into cpufreq to hang. Fix this by creating a new 'unlock' label and jumping to that instead. Fixes: bd0fa9bb455d ("cpufreq: Return error if ->get() failed in cpufreq_update_policy()") Link: https://devtalk.nvidia.com/default/topic/751903/kernel-3-15-and-nv-drivers-337-340-failed-to-initialize-the-nvidia-kernel-module-gtx-550-ti-/ Signed-off-by: Aaron Plattner Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/cpufreq/cpufreq.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2166,10 +2166,8 @@ int cpufreq_update_policy(unsigned int c struct cpufreq_policy new_policy; int ret; - if (!policy) { - ret = -ENODEV; - goto no_policy; - } + if (!policy) + return -ENODEV; down_write(&policy->rwsem); @@ -2188,7 +2186,7 @@ int cpufreq_update_policy(unsigned int c new_policy.cur = cpufreq_driver->get(cpu); if (WARN_ON(!new_policy.cur)) { ret = -EIO; - goto no_policy; + goto unlock; } if (!policy->cur) { @@ -2203,10 +2201,10 @@ int cpufreq_update_policy(unsigned int c ret = cpufreq_set_policy(policy, &new_policy); +unlock: up_write(&policy->rwsem); cpufreq_cpu_put(policy); -no_policy: return ret; } EXPORT_SYMBOL(cpufreq_update_policy);