On 12/03/2012 06:41 PM, Peter Hurley wrote:
The lock logic for tty_set_ldisc() is wrong. Despite existing code in
tty_set_ldisc() and tty_ldisc_hangup(), the ldisc_mutex does **not**
(and should not) play a role in acquiring or releasing ldisc references.
The only thing that needs to happen here is below (don't actually use
below because I just hand-edited it):
Hmm. What about I stay in sync with the code that is already in tree
and if the wrong locking gets removed in both places later on?
Alan, what do you prefer?
See http://lkml.org/lkml/2012/11/21/347
drivers/tty/tty_ldisc.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 0f2a2c5..fb76818 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -930,16 +930,21 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty)
*/
- tty_lock_pair(tty, o_tty);
tty_ldisc_halt(tty);
tty_ldisc_flush_works(tty);
+ tty_lock_pair(tty, o_tty);
/* This will need doing differently if we need to lock */
tty_ldisc_kill(tty);
-
if (o_tty)
tty_ldisc_kill(o_tty);
Sebastian
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
