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To: "wim@iguana.be" <wim@iguana.be>
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From: Guenter Roeck <linux@roeck-us.net>
Subject: Stopping watchdog in watchdog driver remove functions
Message-ID: <64c83c02-2c64-c536-3302-8079f438f0ab@roeck-us.net>
Date: Sat, 31 Dec 2016 11:44:15 -0800
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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