From: Dan Carpenter <error27@gmail.com>
Date: Wed, 13 Dec 2006 08:35:09 +0000 (-0800)
Subject: [PATCH] tty_io.c balance tty_ldisc_ref()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=b3f13debd593dbd7242a4ecf6c9b4d529805e5a0;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

[PATCH] tty_io.c balance tty_ldisc_ref()

tty_ldisc_deref() should only be called when tty_ldisc_ref() succeeds
otherwise it triggers a BUG().  There's already a function
tty_ldisc_flush() that flushes properly.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index a928f6af52f2..47a6eacb10bc 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -3335,18 +3335,13 @@ static void __do_SAK(struct work_struct *work)
 	int session;
 	int		i;
 	struct file	*filp;
-	struct tty_ldisc *disc;
 	struct fdtable *fdt;
 	
 	if (!tty)
 		return;
 	session = tty->session;
 	
-	/* We don't want an ldisc switch during this */
-	disc = tty_ldisc_ref(tty);
-	if (disc && disc->flush_buffer)
-		disc->flush_buffer(tty);
-	tty_ldisc_deref(disc);
+	tty_ldisc_flush(tty);
 
 	if (tty->driver->flush_buffer)
 		tty->driver->flush_buffer(tty);