On Sat, Dec 11, 2010 at 02:19:20PM +0100, Jiri Slaby wrote: > On 12/08/2010 04:50 PM, Greg KH wrote: > > On Wed, Dec 08, 2010 at 04:09:26PM +0100, Jiri Slaby wrote: > >> On 12/08/2010 04:02 PM, Greg KH wrote: > >>> On Wed, Dec 08, 2010 at 07:24:46AM +0100, Jiri Slaby wrote: > >>>> On 12/08/2010 01:43 AM, Greg KH wrote: > >>>>> 2.6.32-stable review patch. If anyone has any objections, please let > >>>>> us know. > >>>>> > >>>>> ------------------ > >>>>> > >>>>> From: Jiri Slaby <[email protected]> > >>>>> > >>>>> 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 <[email protected]> > >>>>> Cc: Alan Cox <[email protected]> > >>>>> Reported-by: Sergey Lapin <[email protected]> > >>>>> Tested-by: Sergey Lapin <[email protected]> > >>>>> Signed-off-by: Greg Kroah-Hartman <[email protected]> > >>>>> > >>>>> --- > >>>>> drivers/char/tty_ldisc.c | 9 +++++++-- > >>>>> 1 file changed, 7 insertions(+), 2 deletions(-) > >>>>> > >>>>> --- a/drivers/char/tty_ldisc.c > >>>>> +++ b/drivers/char/tty_ldisc.c > >>>>> @@ -444,9 +444,14 @@ static void tty_set_termios_ldisc(struct > >>>>> > >>>>> 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; > >>>> > >>>> Whoops, this should write return ret; (with int ret = 0;) > >>>> > >>>> Do you want me to send the patch against rebased on .32? > >>> > >>> No, send it based on Linus's tree as it's wrong there, right? Then it > >>> will move through to the stable kernels. > >> > >> Nope, in 2.6.36 and newer it looks differently, only the .32 backport is > >> broken. > > > > Ick, ok, sorry about that. Yes, can you just send me a tiny patch that > > I can merge with the .32 patch to resolve this? > > JFYI, Ben did last night in: > [PATCH] TTY: Fix error return from tty_ldisc_open()
Yup, I now see that, thanks, I'll go cut a new .32 release with that fix in it. greg k-h _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
