From: Park Bumgyu <bumgyu.park@samsung.com>
Date: Tue, 1 Aug 2017 10:36:30 +0000 (+0900)
Subject: [COMMON] cpufreq: prevent to access NULL sg_policy
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=b299d420c73bf18692b377881f7c56f4902222d0;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

[COMMON] cpufreq: prevent to access NULL sg_policy

Change-Id: If6a532db0dc3a7fe7b3146fd48c03550d5e16fbd
Signed-off-by: Park Bumgyu <bumgyu.park@samsung.com>
---

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 8f91c8a92011..1a4449f59d4a 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -764,10 +764,10 @@ static void sugov_exit(struct cpufreq_policy *policy)
 	if (!count)
 		sugov_tunables_free(tunables);
 
-	mutex_unlock(&global_tunables_lock);
-
 	sugov_kthread_stop(sg_policy);
 	sugov_policy_free(sg_policy);
+	mutex_unlock(&global_tunables_lock);
+
 	cpufreq_disable_fast_switch(policy);
 }
 
@@ -828,6 +828,13 @@ static void sugov_limits(struct cpufreq_policy *policy)
 {
 	struct sugov_policy *sg_policy = policy->governor_data;
 
+	mutex_lock(&global_tunables_lock);
+
+	if (!sg_policy) {
+		mutex_unlock(&global_tunables_lock);
+		return;
+	}
+
 	if (!policy->fast_switch_enabled) {
 		mutex_lock(&sg_policy->work_lock);
 		cpufreq_policy_apply_limits(policy);
@@ -835,6 +842,8 @@ static void sugov_limits(struct cpufreq_policy *policy)
 	}
 
 	sg_policy->need_freq_update = true;
+
+	mutex_unlock(&global_tunables_lock);
 }
 
 static struct cpufreq_governor schedutil_gov = {