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-rw-r--r--drivers/cpufreq/cpufreq.c13
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 4da28444b235..3938c7817095 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -61,6 +61,8 @@ static DEFINE_SPINLOCK(cpufreq_driver_lock);
* are concerned with are online after they get the lock.
* - Governor routines that can be called in cpufreq hotplug path should not
* take this sem as top level hotplug notifier handler takes this.
+ * - Lock should not be held across
+ * __cpufreq_governor(data, CPUFREQ_GOV_STOP);
*/
static DEFINE_PER_CPU(int, policy_cpu);
static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem);
@@ -1707,8 +1709,17 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
dprintk("governor switch\n");
/* end old governor */
- if (data->governor)
+ if (data->governor) {
+ /*
+ * Need to release the rwsem around governor
+ * stop due to lock dependency between
+ * cancel_delayed_work_sync and the read lock
+ * taken in the delayed work handler.
+ */
+ unlock_policy_rwsem_write(data->cpu);
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
+ lock_policy_rwsem_write(data->cpu);
+ }
/* start new governor */
data->governor = policy->governor;
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