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);
 
@@ -369,7 +366,7 @@
 
 static int
 ttydev_close(struct cdev *dev, int fflag, int devtype __unused,
-    struct thread *td __unused)
+    struct thread *td)
 {
 	struct tty *tp = dev->si_drv1;
 
@@ -392,8 +389,11 @@
 	}
 
 	/* If revoking, flush output now to avoid draining it later. */
-	if (fflag & FREVOKE)
+	if ((fflag & FREVOKE) != 0) {
 		tty_flush(tp, FWRITE);
+		knlist_delete(&tp->t_inpoll.si_note, td, 1);
+		knlist_delete(&tp->t_outpoll.si_note, td, 1);
+	}
 
 	tp->t_flags &= ~TF_EXCLUDE;
 
@@ -1120,6 +1120,8 @@
 	ttyoutq_free(&tp->t_outq);
 	seldrain(&tp->t_inpoll);
 	seldrain(&tp->t_outpoll);
+	knlist_clear(&tp->t_inpoll.si_note, 0);
+	knlist_clear(&tp->t_outpoll.si_note, 0);
 	knlist_destroy(&tp->t_inpoll.si_note);
 	knlist_destroy(&tp->t_outpoll.si_note);