Index: head/sys/kern/kern_rmlock.c
===================================================================
--- head/sys/kern/kern_rmlock.c
+++ head/sys/kern/kern_rmlock.c
@@ -407,9 +407,11 @@
 				return (0);
 		}
 	} else {
-		if (rm->lock_object.lo_flags & LO_SLEEPABLE)
+		if (rm->lock_object.lo_flags & LO_SLEEPABLE) {
+			THREAD_SLEEPING_OK();
 			sx_xlock(&rm->rm_lock_sx);
-		else
+			THREAD_NO_SLEEPING();
+		} else
 			mtx_lock(&rm->rm_lock_mtx);
 	}