linux-kernel - Stopping watchdog in watchdog driver remove functions

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Message-ID: <64c83c02-2c64-c536-3302-8079f438f0ab@roeck-us.net>
Date:   Sat, 31 Dec 2016 11:44:15 -0800
From:   Guenter Roeck <linux@...ck-us.net>
To:     "wim@...ana.be" <wim@...ana.be>
Cc:     "linux-watchdog@...r.kernel.org" <linux-watchdog@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Laxman Dewangan <ldewangan@...dia.com>,
        Mans Rullgard <mans@...sr.com>,
        Justin Chen <justinpopo6@...il.com>,
        Wenyou Yang <wenyou.yang@...el.com>,
        Naidu Tellapati <naidu.tellapati@...il.com>
Subject: Stopping watchdog in watchdog driver remove functions

Hi,

I noticed that several watchdog drivers stop the watchdog in trhe driver remove function.
A non-exhaustive list of drivers doing that is

	drivers/watchdog/bcm7038_wdt.c
	drivers/watchdog/cadence_wdt.c
	drivers/watchdog/imgpdc_wdt.c
	drivers/watchdog/jz4740_wdt.c
	drivers/watchdog/kempld_wdt.c
	drivers/watchdog/max77620_wdt.c
	drivers/watchdog/moxart_wdt.c
	drivers/watchdog/sama5d4_wdt.c
	drivers/watchdog/tangox_wdt.c
	drivers/watchdog/tegra_wdt.c

Since a watchdog has to be closed for its driver to be removable, one situation
where a watchdog is still running on unload is where the watchdog was opened but
not closed properly (eg by killing the watchdog application, or if the 'nowayout'
flag is set).

Given that, does it even make sense to stop the watchdog in the remove function ?
Should it even be permitted ?

Thanks,
Guenter