diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c
index ede365d05387087ba4110a9f97fc74ba6c1971ef..b9371d5bf7906b48d4b340c5a8756c3fa132f516 100644
--- a/drivers/char/n_tty.c
+++ b/drivers/char/n_tty.c
@@ -1384,8 +1384,10 @@ static ssize_t read_chan(struct tty_struct *tty, struct file *file,
 		 * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode,
 		 * we won't get any more characters.
 		 */
-		if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE)
+		if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE) {
+			n_tty_set_room(tty);
 			check_unthrottle(tty);
+		}
 
 		if (b - buf >= minimum)
 			break;