From 24625640fe278feac753e36888ff1d335d39964b Mon Sep 17 00:00:00 2001 From: George Spelvin Date: Sun, 10 Feb 2013 04:41:56 -0500 Subject: [PATCH] pps: Use pps_lookup_dev to reduce ldisc coupling commit 03a7ffe4e542310838bac70ef85acc17536b6d7c upstream. Now that N_TTY uses tty->disc_data for its private data, 'subclass' ldiscs cannot use ->disc_data for their own private data. (This is a regression is v3.8-rc1) Use pps_lookup_dev to associate the tty with the pps source instead. This fixes a crashing regression in 3.8-rc1. Signed-off-by: George Spelvin Acked-by: Rodolfo Giometti Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/pps/clients/pps-ldisc.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/pps/clients/pps-ldisc.c b/drivers/pps/clients/pps-ldisc.c index 79451f2dea6a..60cee9e0ecb3 100644 --- a/drivers/pps/clients/pps-ldisc.c +++ b/drivers/pps/clients/pps-ldisc.c @@ -31,7 +31,7 @@ static void pps_tty_dcd_change(struct tty_struct *tty, unsigned int status, struct pps_event_time *ts) { - struct pps_device *pps = (struct pps_device *)tty->disc_data; + struct pps_device *pps = pps_lookup_dev(tty); BUG_ON(pps == NULL); @@ -67,9 +67,9 @@ static int pps_tty_open(struct tty_struct *tty) pr_err("cannot register PPS source \"%s\"\n", info.path); return -ENOMEM; } - tty->disc_data = pps; + pps->lookup_cookie = tty; - /* Should open N_TTY ldisc too */ + /* Now open the base class N_TTY ldisc */ ret = alias_n_tty_open(tty); if (ret < 0) { pr_err("cannot open tty ldisc \"%s\"\n", info.path); @@ -81,7 +81,6 @@ static int pps_tty_open(struct tty_struct *tty) return 0; err_unregister: - tty->disc_data = NULL; pps_unregister_source(pps); return ret; } @@ -90,11 +89,10 @@ static void (*alias_n_tty_close)(struct tty_struct *tty); static void pps_tty_close(struct tty_struct *tty) { - struct pps_device *pps = (struct pps_device *)tty->disc_data; + struct pps_device *pps = pps_lookup_dev(tty); alias_n_tty_close(tty); - tty->disc_data = NULL; dev_info(pps->dev, "removed\n"); pps_unregister_source(pps); } -- 2.39.2