Governor's owner refcount usage was broken. We should increment refcount only
when CPUFREQ_GOV_POLICY_INIT event has come and should decrement only if
CPUFREQ_GOV_POLICY_EXIT has come.

Lets fix it.

Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
 drivers/cpufreq/cpufreq.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index e9b969f..74d4969 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1707,8 +1707,9 @@ static int __cpufreq_governor(struct cpufreq_policy 
*policy,
                }
        }
 
-       if (!try_module_get(policy->governor->owner))
-               return -EINVAL;
+       if (event == CPUFREQ_GOV_POLICY_INIT)
+               if (!try_module_get(policy->governor->owner))
+                       return -EINVAL;
 
        pr_debug("__cpufreq_governor for CPU %u, event %u\n",
                                                policy->cpu, event);
@@ -1717,6 +1718,8 @@ static int __cpufreq_governor(struct cpufreq_policy 
*policy,
        if ((!policy->governor_enabled && (event == CPUFREQ_GOV_STOP)) ||
            (policy->governor_enabled && (event == CPUFREQ_GOV_START))) {
                mutex_unlock(&cpufreq_governor_lock);
+               if (event == CPUFREQ_GOV_POLICY_INIT)
+                       module_put(policy->governor->owner);
                return -EBUSY;
        }
 
@@ -1744,11 +1747,8 @@ static int __cpufreq_governor(struct cpufreq_policy 
*policy,
                mutex_unlock(&cpufreq_governor_lock);
        }
 
-       /* we keep one module reference alive for
-                       each CPU governed by this CPU */
-       if ((event != CPUFREQ_GOV_START) || ret)
-               module_put(policy->governor->owner);
-       if ((event == CPUFREQ_GOV_STOP) && !ret)
+       if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) ||
+                       ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret))
                module_put(policy->governor->owner);
 
        return ret;
-- 
1.7.12.rc2.18.g61b472e

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