tty: the rest, stop using tty_schedule_flip()

stable inclusion
from stable-v5.10.134
commit 4d374625cca21ce4f9cdd58170d070b400910ae2
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5A5Y1
CVE: CVE-2022-1462

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4d374625cca21ce4f9cdd58170d070b400910ae2

--------------------------------

commit b68b9144 upstream.

Since commit a9c3f68f (tty: Fix low_latency BUG) in 2014,
tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). We are
going to remove the latter (as it is used less), so call the former in
the rest of the users.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
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: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: NJohan Hovold <johan@kernel.org>
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20211122111648.30379-3-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYi Yang <yiyang13@huawei.com>
Reviewed-by: NWang Weiyang <wangweiyang2@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/alpha/kernel/srmcons.c

@@ -59,7 +59,7 @@ srmcons_do_receive_chars(struct tty_port *port)
 	} while((result.bits.status & 1) && (++loops < 10));
 
 	if (count)
-		tty_schedule_flip(port);
+		tty_flip_buffer_push(port);
 
 	return count;
 }

drivers/accessibility/speakup/spk_ttyio.c

@@ -88,7 +88,7 @@ static int spk_ttyio_receive_buf2(struct tty_struct *tty,
 	}
 
 	if (!ldisc_data->buf_free)
-		/* ttyio_in will tty_schedule_flip */
+		/* ttyio_in will tty_flip_buffer_push */
 		return 0;
 
 	/* Make sure the consumer has read buf before we have seen
@@ -334,7 +334,7 @@ static unsigned char ttyio_in(int timeout)
 	mb();
 	ldisc_data->buf_free = true;
 	/* Let TTY push more characters */
-	tty_schedule_flip(speakup_tty->port);
+	tty_flip_buffer_push(speakup_tty->port);
 
 	return rv;
 }

drivers/s390/char/keyboard.h

@@ -56,7 +56,7 @@ static inline void
 kbd_put_queue(struct tty_port *port, int ch)
 {
 	tty_insert_flip_char(port, ch, 0);
-	tty_schedule_flip(port);
+	tty_flip_buffer_push(port);
 }
 
 static inline void
@@ -64,5 +64,5 @@ kbd_puts_queue(struct tty_port *port, char *cp)
 {
 	while (*cp)
 		tty_insert_flip_char(port, *cp++, 0);
-	tty_schedule_flip(port);
+	tty_flip_buffer_push(port);
 }