diff options
| author | Jiri Slaby <jslaby@suse.cz> | 2010-11-25 00:27:54 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-12-09 13:26:47 -0800 |
| commit | 004e147bd32cda45140354ace87f55abed3b82cb (patch) | |
| tree | e8142693f0e45525c3fe6c4e8fd846ae08ae475f /drivers/char | |
| parent | d22ed6613136322b8cd6a126b75f5c8175f5f00c (diff) | |
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:
[<c1030321>] ? warn_slowpath_common+0x5e/0x8a
[<c1030357>] ? warn_slowpath_null+0xa/0xc
[<c119311c>] ? tty_ldisc_open+0x26/0x38
[<c11936c5>] ? 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 <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Reported-by: Sergey Lapin <slapin@ossfans.org>
Tested-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tty_ldisc.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c index a4d60e4ea032..8b9f1a5c8be8 100644 --- a/drivers/char/tty_ldisc.c +++ b/drivers/char/tty_ldisc.c @@ -444,9 +444,14 @@ static void tty_set_termios_ldisc(struct tty_struct *tty, int num) static int tty_ldisc_open(struct tty_struct *tty, struct tty_ldisc *ld) { + int ret; + WARN_ON(test_and_set_bit(TTY_LDISC_OPEN, &tty->flags)); - if (ld->ops->open) - return ld->ops->open(tty); + if (ld->ops->open) { + ret = ld->ops->open(tty); + if (ret) + clear_bit(TTY_LDISC_OPEN, &tty->flags); + } return 0; } |