diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 67458468f1a8508becb63997f20271de14df458e..73e7195f999713e5f7aa112cd08779fd38a48689 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -83,6 +83,7 @@ extern void rcu_sched_force_quiescent_state(void);
 /* A context switch is a grace period for RCU-sched and RCU-bh. */
 static inline int rcu_blocking_is_gp(void)
 {
+	might_sleep();  /* Check for RCU read-side critical section. */
 	return num_online_cpus() == 1;
 }