From 786e908ffee39c89aa51ed68c5e86b373ac61254 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Thu, 25 Nov 2010 00:27:54 +0100 Subject: [PATCH] TTY: ldisc, fix open flag handling commit 7f90cfc505d613f4faf096e0d84ffe99208057d9 upstream. When a concrete ldisc open fails in tty_ldisc_open, we forget to clear TTY_LDISC_OPEN. This causes a false warning on the next ldisc open: WARNING: at drivers/char/tty_ldisc.c:445 tty_ldisc_open+0x26/0x38() Hardware name: System Product Name Modules linked in: ... Pid: 5251, comm: a.out Tainted: G W 2.6.32-5-686 #1 Call Trace: [] ? warn_slowpath_common+0x5e/0x8a [] ? warn_slowpath_null+0xa/0xc [] ? tty_ldisc_open+0x26/0x38 [] ? tty_set_ldisc+0x218/0x304 ... So clear the bit when failing... Introduced in c65c9bc3efa (tty: rewrite the ldisc locking) back in 2.6.31-rc1. Signed-off-by: Jiri Slaby Cc: Alan Cox Reported-by: Sergey Lapin Tested-by: Sergey Lapin Signed-off-by: Greg Kroah-Hartman --- drivers/char/tty_ldisc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c index d8e96b005023..4214d58276f7 100644 --- a/drivers/char/tty_ldisc.c +++ b/drivers/char/tty_ldisc.c @@ -454,6 +454,8 @@ static int tty_ldisc_open(struct tty_struct *tty, struct tty_ldisc *ld) /* BTM here locks versus a hangup event */ WARN_ON(!tty_locked()); ret = ld->ops->open(tty); + if (ret) + clear_bit(TTY_LDISC_OPEN, &tty->flags); return ret; } return 0; -- 2.34.1