tty: no checking of tty_unregister_ldisc

tty_unregister_ldisc now returns 0 = success. No need to check the
return value. In fact, the users only warned if an error occured and
didn't do anything useful anyway -- the ldisc module was unloaded in any
case.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: William Hubbs <w.d.hubbs@gmail.com>
Cc: Chris Brannon <chris@the-brannons.com>
Cc: Kirk Reiser <kirk@reisers.ca>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Andreas Koensgen <ajk@comnets.uni-bremen.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rodolfo Giometti <giometti@enneenne.com>
Cc: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Link: https://lore.kernel.org/r/20210505091928.22010-19-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

6 files changed, 6 insertions, 24 deletions

diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index 03a2dbd3c367..d42ec7d1bc14 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -784,9 +784,7 @@ static void __exit slcan_exit(void)
 	kfree(slcan_devs);
 	slcan_devs = NULL;
 
-	i = tty_unregister_ldisc(&slc_ldisc);
-	if (i)
-		printk(KERN_ERR "slcan: can't unregister ldisc (err %d)\n", i);
+	tty_unregister_ldisc(&slc_ldisc);
 }
 
 module_init(slcan_init);
diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index aac24f9caceb..686c38c46113 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -774,15 +774,9 @@ static int __init sixpack_init_driver(void)
 	return status;
 }
 
-static const char msg_unregfail[] = KERN_ERR \
-	"6pack: can't unregister line discipline (err = %d)\n";
-
 static void __exit sixpack_exit_driver(void)
 {
-	int ret;
-
-	if ((ret = tty_unregister_ldisc(&sp_ldisc)))
-		printk(msg_unregfail, ret);
+	tty_unregister_ldisc(&sp_ldisc);
 }
 
 /* encode an AX.25 packet into 6pack */
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c
index 750c6afc9302..e3294a0a9800 100644
--- a/drivers/net/hamradio/mkiss.c
+++ b/drivers/net/hamradio/mkiss.c
@@ -960,15 +960,9 @@ static int __init mkiss_init_driver(void)
 	return status;
 }
 
-static const char msg_unregfail[] = KERN_ERR \
-	"mkiss: can't unregister line discipline (err = %d)\n";
-
 static void __exit mkiss_exit_driver(void)
 {
-	int ret;
-
-	if ((ret = tty_unregister_ldisc(&ax_ldisc)))
-		printk(msg_unregfail, ret);
+	tty_unregister_ldisc(&ax_ldisc);
 }
 
 MODULE_AUTHOR("Ralf Baechle DL5RB <ralf@linux-mips.org>");
diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c
index b2d454d01eba..29a93d6bfe37 100644
--- a/drivers/net/ppp/ppp_async.c
+++ b/drivers/net/ppp/ppp_async.c
@@ -1016,8 +1016,7 @@ static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
 
 static void __exit ppp_async_cleanup(void)
 {
-	if (tty_unregister_ldisc(&ppp_ldisc) != 0)
-		printk(KERN_ERR "failed to unregister PPP line discipline\n");
+	tty_unregister_ldisc(&ppp_ldisc);
 }
 
 module_init(ppp_async_init);
diff --git a/drivers/net/ppp/ppp_synctty.c b/drivers/net/ppp/ppp_synctty.c
index ca403bde56fb..af3e048695b6 100644
--- a/drivers/net/ppp/ppp_synctty.c
+++ b/drivers/net/ppp/ppp_synctty.c
@@ -727,8 +727,7 @@ err:
 static void __exit
 ppp_sync_cleanup(void)
 {
-	if (tty_unregister_ldisc(&ppp_sync_ldisc) != 0)
-		printk(KERN_ERR "failed to unregister Sync PPP line discipline\n");
+	tty_unregister_ldisc(&ppp_sync_ldisc);
 }
 
 module_init(ppp_sync_init);
diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c
index 867efff40a0e..dc84cb844319 100644
--- a/drivers/net/slip/slip.c
+++ b/drivers/net/slip/slip.c
@@ -1360,9 +1360,7 @@ static void __exit slip_exit(void)
 	kfree(slip_devs);
 	slip_devs = NULL;
 
-	i = tty_unregister_ldisc(&sl_ldisc);
-	if (i != 0)
-		printk(KERN_ERR "SLIP: can't unregister line discipline (err = %d)\n", i);
+	tty_unregister_ldisc(&sl_ldisc);
 }
 
 module_init(slip_init);