From: Yuho Choi Date: Mon, 1 Jun 2026 19:20:05 +0000 (-0400) Subject: watchdog: unregister PM notifier on watchdog unregister X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a298c7302ee9584a7a1ac1e8acbede8d98ab51a4;p=thirdparty%2Flinux.git 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 Link: https://lore.kernel.org/r/20260601192005.1970805-1-dbgh9129@gmail.com Signed-off-by: Guenter Roeck --- diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c index 866874b268191..f4097aefaf491 100644 --- a/drivers/watchdog/watchdog_core.c +++ b/drivers/watchdog/watchdog_core.c @@ -391,6 +391,9 @@ static void __watchdog_unregister_device(struct watchdog_device *wdd) if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status)) unregister_reboot_notifier(&wdd->reboot_nb); + if (test_bit(WDOG_NO_PING_ON_SUSPEND, &wdd->status)) + unregister_pm_notifier(&wdd->pm_nb); + watchdog_dev_unregister(wdd); ida_free(&watchdog_ida, wdd->id); }