copy tty debugging from rawhide

debug-tty-print-dev-name.patch

@@ -0,0 +1,17 @@
+diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
+index 613c852..09c86d2 100644
+--- a/drivers/tty/tty_io.c
++++ b/drivers/tty/tty_io.c
+@@ -1322,7 +1322,11 @@ static int tty_reopen(struct tty_struct *tty)
+ 	tty->driver = driver; /* N.B. why do this every time?? */
+ 
+ 	mutex_lock(&tty->ldisc_mutex);
+-	WARN_ON(!test_bit(TTY_LDISC, &tty->flags));
++	if (!test_bit(TTY_LDISC, &tty->flags)) {
++		printk("%s: !test_bit(TTY_LDISC, &tty->flags) dev=%s ldisc=%s\n",
++			__func__, tty->name, tty->ldisc ? tty->ldisc->ops ? tty->ldisc->ops->name : NULL : NULL);
++		WARN_ON(1);
++	}
+ 	mutex_unlock(&tty->ldisc_mutex);
+ 
+ 	return 0;