From: Daniel Starke <daniel.starke@xxxxxxxxxxx> The current DLCI release order starts with the control channel followed by the user channels. Reverse this order to keep the control channel open until all user channels have been released. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Daniel Starke <daniel.starke@xxxxxxxxxxx> --- drivers/tty/n_gsm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index cc90b03ce005..6b953dfbb155 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2146,8 +2146,8 @@ static void gsm_cleanup_mux(struct gsm_mux *gsm, bool disc) /* Finish outstanding timers, making sure they are done */ del_timer_sync(&gsm->t2_timer); - /* Free up any link layer users */ - for (i = 0; i < NUM_DLCI; i++) + /* Free up any link layer users and finally the control channel */ + for (i = NUM_DLCI - 1; i >= 0; i--) if (gsm->dlci[i]) gsm_dlci_release(gsm->dlci[i]); mutex_unlock(&gsm->mutex); -- 2.25.1