pps: Don't crash the machine when exiting will do

PPS is not really the must-have subsystem that warrants crashing
the machine if the ldisc interface is broken.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
George Spelvin 2013-02-10 04:43:41 -05:00 committed by Greg Kroah-Hartman
parent d953e0e837
commit ce3da1a654

View file

@ -25,6 +25,7 @@
#include <linux/serial_core.h>
#include <linux/tty.h>
#include <linux/pps_kernel.h>
#include <linux/bug.h>
#define PPS_TTY_MAGIC 0x0001
@ -33,7 +34,12 @@ static void pps_tty_dcd_change(struct tty_struct *tty, unsigned int status,
{
struct pps_device *pps = pps_lookup_dev(tty);
BUG_ON(pps == NULL);
/*
* This should never fail, but the ldisc locking is very
* convoluted, so don't crash just in case.
*/
if (WARN_ON_ONCE(pps == NULL))
return;
/* Now do the PPS event report */
pps_event(pps, ts, status ? PPS_CAPTUREASSERT :
@ -93,6 +99,9 @@ static void pps_tty_close(struct tty_struct *tty)
alias_n_tty_close(tty);
if (WARN_ON(!pps))
return;
dev_info(pps->dev, "removed\n");
pps_unregister_source(pps);
}