diff --git a/sys/kern/tty.c b/sys/kern/tty.c
--- a/sys/kern/tty.c
+++ b/sys/kern/tty.c
@@ -253,9 +253,6 @@
 	ttyoutq_free(&tp->t_outq);
 	tp->t_outlow = 0;
 
-	knlist_clear(&tp->t_inpoll.si_note, 1);
-	knlist_clear(&tp->t_outpoll.si_note, 1);
-
 	if (!tty_gone(tp))
 		ttydevsw_close(tp);
 
@@ -403,6 +400,11 @@
 	cv_broadcast(&tp->t_bgwait);
 	cv_broadcast(&tp->t_dcdwait);
 
+	if (fflag & FREVOKE) {
+		knlist_delete(&tp->t_inpoll.si_note, curthread, 1);
+		knlist_delete(&tp->t_outpoll.si_note, curthread, 1);
+	}
+
 	ttydev_leave(tp);
 
 	return (0);