watchdog: unregister PM notifier on watchdog unregister

watchdog_register_device() registers wdd->pm_nb when
WDOG_NO_PING_ON_SUSPEND is set, but watchdog_unregister_device() does not
remove it. This leaves an embedded notifier block on the PM notifier chain
after the watchdog device has been unregistered.

A later suspend/resume notification can then call watchdog_pm_notifier()
with a stale watchdog_device pointer, or at minimum after wdd->wd_data has
been cleared by watchdog_dev_unregister().

Unregister the PM notifier before tearing down the watchdog device.

Fixes: 60bcd91aafd2 ("watchdog: introduce watchdog_dev_suspend/resume")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Link: https://lore.kernel.org/r/20260601192005.1970805-1-dbgh9129@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

0 files changed, 0 insertions, 0 deletions