[PATCH 6/7] tty: Clarify multiple-references comment in TIOCSETD ioctl

From: Peter Hurley
Date: Tue Apr 16 2013 - 06:16:41 EST


Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/tty_ldisc.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 84ba790..9725c94 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -567,13 +567,15 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
tty_ldisc_restore(tty, old_ldisc);
}

- /* At this point we hold a reference to the new ldisc and a
- a reference to the old ldisc. If we ended up flipping back
- to the existing ldisc we have two references to it */
-
if (tty->ldisc->ops->num != old_ldisc->ops->num && tty->ops->set_ldisc)
tty->ops->set_ldisc(tty);

+ /* At this point we hold a reference to the new ldisc and a
+ reference to the old ldisc, or we hold two references to
+ the old ldisc (if it was restored as part of error cleanup
+ above). In either case, releasing a single reference from
+ the old ldisc is correct. */
+
tty_ldisc_put(old_ldisc);

/*
--
1.8.1.2

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