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Subject: Re: [PATCH 2/5] watchdog: Separate and maintain variables based on
 variable lifetime
To: Tomas Winkler <tomasw@gmail.com>
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From: Guenter Roeck <linux@roeck-us.net>
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Date: Tue, 22 Dec 2015 16:32:51 -0800
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On 12/22/2015 02:05 PM, Tomas Winkler wrote:

>
>  > Do you see a situation where holding the lock between calls into the driver
>  > might be a problem ?
>
> I don't think u are holding the lock now in watchdog_unregister when WDOG_UNREGISTERED was dropped.

the lock is held while clearing the pointers:

	mutex_lock(&wd_data->lock);
         wd_data->wdd = NULL;
         wdd->wd_data = NULL;
         mutex_unlock(&wd_data->lock);

Guenter