diff --git a/sched/thread.c b/sched/thread.c
index 3e3e675..3c28655 100644
--- a/sched/thread.c
+++ b/sched/thread.c
@@ -136,7 +136,10 @@ void thread_awaken(struct thread *thr)
 	}
 
 	thr->tr_state = THREAD_READY;
+	unsigned long flags;
+	rq_lock(rq, &flags);
 	rq_enqueue(rq, thr);
+	rq_unlock(rq, flags);
 }
 
 struct thread *create_kernel_thread(void (*fn)(void))