From 970cf9a97a27d3f9a72a17aa6aedb47758478c33 Mon Sep 17 00:00:00 2001
From: Sven Schnelle <svens@linux.ibm.com>
Date: Thu, 17 Nov 2022 17:52:40 +0100
Subject: [PATCH] s390/tty3270: ignore NUL characters

With 'TERM=vt220' zsh is sending several NUL characters with
the prompt to the tty. Both xterm and the linux drm console
seem to ignore them. Ignore them in tty3270 as well.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
 drivers/s390/char/con3270.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/s390/char/con3270.c b/drivers/s390/char/con3270.c
index 9c816d1239ebc..7ff116c387156 100644
--- a/drivers/s390/char/con3270.c
+++ b/drivers/s390/char/con3270.c
@@ -1732,6 +1732,8 @@ static void tty3270_do_write(struct tty3270 *tp, struct tty_struct *tty,
 		}
 
 		switch (buf[i_msg]) {
+		case 0x00:
+			break;
 		case 0x07:		/* '\a' -- Alarm */
 			tp->wcc |= TW_PLUSALARM;
 			break;
-- 
2.30.2