From 034e5ac4cccd09872592a46decd38d5f24047f10 Mon Sep 17 00:00:00 2001 Message-Id: <034e5ac4cccd09872592a46decd38d5f24047f10.1363954124.git.viresh.kumar@linaro.org> From: Viresh Kumar Date: Fri, 22 Mar 2013 15:15:48 +0530 Subject: [PATCH] cpufreq: stats: do cpufreq_cpu_put() corresponding to cpufreq_cpu_get In cpufreq_stats_free_sysfs() we aren't balancing calls to cpufreq_cpu_get() with cpufreq_cpu_put(). This will never let us have ref count to policy->kobj as zero. We will get a hang if somehow cpufreq_driver_unregister() is called. And that can happen when we compile our driver as module and insmod/rmmod it. Signed-off-by: Viresh Kumar --- drivers/cpufreq/cpufreq_stats.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index 2fd779e..bfd6273 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -180,15 +180,19 @@ static void cpufreq_stats_free_sysfs(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); - if (!cpufreq_frequency_get_table(cpu)) + if (!policy) return; - if (policy && !policy_is_shared(policy)) { + if (!cpufreq_frequency_get_table(cpu)) + goto put_ref; + + if (!policy_is_shared(policy)) { pr_debug("%s: Free sysfs stat\n", __func__); sysfs_remove_group(&policy->kobj, &stats_attr_group); } - if (policy) - cpufreq_cpu_put(policy); + +put_ref: + cpufreq_cpu_put(policy); } static int cpufreq_stats_create_table(struct cpufreq_policy *policy, -- 1.7.12.rc2.18.g61b472e