From: Alan Cox <alan@linux.intel.com>
Date: Tue, 16 Jun 2009 16:00:40 +0000 (+0100)
Subject: ldisc: Make sure the ldisc isn't active when we close it
X-Git-Tag: firefly_0821_release~13899^2~7
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=52856ed732aeab5e8e0b7c9e2a7a3d31736218ab;p=firefly-linux-kernel-4.4.55.git

ldisc: Make sure the ldisc isn't active when we close it

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c
index 94b3e06d73ec..874c2486c034 100644
--- a/drivers/char/tty_ldisc.c
+++ b/drivers/char/tty_ldisc.c
@@ -793,6 +793,8 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 		/* Avoid racing set_ldisc */
 		mutex_lock(&tty->ldisc_mutex);
 		/* Switch back to N_TTY */
+		tty_ldisc_halt(tty);
+		tty_ldisc_wait_idle(tty);
 		tty_ldisc_reinit(tty);
 		/* At this point we have a closed ldisc and we want to
 		   reopen it. We could defer this to the next open but