diff options
-rw-r--r-- | drivers/char/tty_ldisc.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c index 1733d34..e48af9f 100644 --- a/drivers/char/tty_ldisc.c +++ b/drivers/char/tty_ldisc.c @@ -508,8 +508,9 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old) * be obtained while the delayed work queue halt ensures that no more * data is fed to the ldisc. * - * In order to wait for any existing references to complete see - * tty_ldisc_wait_idle. + * You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex) + * in order to make sure any currently executing ldisc work is also + * flushed. */ static int tty_ldisc_halt(struct tty_struct *tty) @@ -753,11 +754,14 @@ void tty_ldisc_hangup(struct tty_struct *tty) * N_TTY. */ if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) { + /* Make sure the old ldisc is quiescent */ + tty_ldisc_halt(tty); + flush_scheduled_work(); + /* Avoid racing set_ldisc or tty_ldisc_release */ mutex_lock(&tty->ldisc_mutex); if (tty->ldisc) { /* Not yet closed */ /* Switch back to N_TTY */ - tty_ldisc_halt(tty); tty_ldisc_reinit(tty); /* At this point we have a closed ldisc and we want to reopen it. We could defer this to the next open but |