diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 2ecd95e4ab1aca33c6e858698d0c16f1b28a19ba..7a74d175287b2f44fc7a7329ce79bd51b5f9b779 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -91,6 +91,9 @@ static unsigned int dbs_enable; /* number of CPUs using this policy */ * (like __cpufreq_driver_target()) is being called with dbs_mutex taken, then * cpu_hotplug lock should be taken before that. Note that cpu_hotplug lock * is recursive for the same process. -Venki + * DEADLOCK ALERT! (2) : do_dbs_timer() must not take the dbs_mutex, because it + * would deadlock with cancel_delayed_work_sync(), which is needed for proper + * raceless workqueue teardown. */ static DEFINE_MUTEX(dbs_mutex); @@ -542,7 +545,7 @@ static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info) static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info) { dbs_info->enable = 0; - cancel_delayed_work(&dbs_info->work); + cancel_delayed_work_sync(&dbs_info->work); } static int cpufreq_governor_dbs(struct cpufreq_policy *policy,