diff options
| -rw-r--r-- | kernel/sched/core.c | 3 | ||||
| -rw-r--r-- | kernel/workqueue.c | 6 |
2 files changed, 6 insertions, 3 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index f6b329bca0c6..c3d12e3762d4 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4120,7 +4120,8 @@ static inline void sched_submit_work(struct task_struct *tsk) * it wants to wake up a task to maintain concurrency. * As this function is called inside the schedule() context, * we disable preemption to avoid it calling schedule() again - * in the possible wakeup of a kworker. + * in the possible wakeup of a kworker and because wq_worker_sleeping() + * requires it. */ if (tsk->flags & (PF_WQ_WORKER | PF_IO_WORKER)) { preempt_disable(); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 3816a18c251e..891ccad5f271 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -858,7 +858,8 @@ void wq_worker_running(struct task_struct *task) * @task: task going to sleep * * This function is called from schedule() when a busy worker is - * going to sleep. + * going to sleep. Preemption needs to be disabled to protect ->sleeping + * assignment. */ void wq_worker_sleeping(struct task_struct *task) { @@ -875,7 +876,8 @@ void wq_worker_sleeping(struct task_struct *task) pool = worker->pool; - if (WARN_ON_ONCE(worker->sleeping)) + /* Return if preempted before wq_worker_running() was reached */ + if (worker->sleeping) return; worker->sleeping = 1; |