diff --git a/kernel/kthread.c b/kernel/kthread.c
index 621467c33fef..b262f47046ca 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -866,9 +866,9 @@ void kthread_delayed_work_timer_fn(struct timer_list *t)
 }
 EXPORT_SYMBOL(kthread_delayed_work_timer_fn);
 
-void __kthread_queue_delayed_work(struct kthread_worker *worker,
-				  struct kthread_delayed_work *dwork,
-				  unsigned long delay)
+static void __kthread_queue_delayed_work(struct kthread_worker *worker,
+					 struct kthread_delayed_work *dwork,
+					 unsigned long delay)
 {
 	struct timer_list *timer = &dwork->timer;
 	struct kthread_work *work = &dwork->work;