cpufreq: interactive: fix NULL pointer dereference at sysfs ops

sysfs ops for target_loads and above_hispeed_delay can be called before
initializing tunables at CPUFREQ_GOV_POLICY_INIT. Create sysfs entries after
initialization.

Change-Id: I50356198d7629731c0d32a3066d61fe8354e0001
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>

diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index 9f63bd1e4feee26b697ae8deb76bf5fb1ea817cb..8297ac69863b539860f08fe18c6b7c8095b014ee 100644 (file)
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -1178,13 +1178,6 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
                        return -ENOMEM;
                }
 
-               rc = sysfs_create_group(get_governor_parent_kobj(policy),
-                               get_sysfs_attr());
-               if (rc) {
-                       kfree(tunables);
-                       return rc;
-               }
-
                tunables->usage_count = 1;
                tunables->above_hispeed_delay = default_above_hispeed_delay;
                tunables->nabove_hispeed_delay =
@@ -1200,16 +1193,26 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
                spin_lock_init(&tunables->target_loads_lock);
                spin_lock_init(&tunables->above_hispeed_delay_lock);
 
+               policy->governor_data = tunables;
+               if (!have_governor_per_policy())
+                       common_tunables = tunables;
+
+               rc = sysfs_create_group(get_governor_parent_kobj(policy),
+                               get_sysfs_attr());
+               if (rc) {
+                       kfree(tunables);
+                       policy->governor_data = NULL;
+                       if (!have_governor_per_policy())
+                               common_tunables = NULL;
+                       return rc;
+               }
+
                if (!policy->governor->initialized) {
                        idle_notifier_register(&cpufreq_interactive_idle_nb);
                        cpufreq_register_notifier(&cpufreq_notifier_block,
                                        CPUFREQ_TRANSITION_NOTIFIER);
                }
 
-               policy->governor_data = tunables;
-               if (!have_governor_per_policy())
-                       common_tunables = tunables;
-
                break;
 
        case CPUFREQ_GOV_POLICY_EXIT: