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Sender: Guenter Roeck <groeck7@gmail.com>
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Date:   Mon, 25 Jul 2022 07:07:17 -0700
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Subject: Re: [PATCH v5] watchdog: add driver for StreamLabs USB watchdog
 device
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To:     Greg KH <gregkh@linuxfoundation.org>,
        Alexey Klimov <klimov.linux@gmail.com>
Cc:     linux-watchdog@vger.kernel.org, wim@linux-watchdog.org,
        oneukum@suse.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, atishp@rivosinc.com,
        atishp@atishpatra.org, yury.norov@gmail.com, aklimov@redhat.com,
        atomlin@redhat.com
References: <20220725030605.1808710-1-klimov.linux@gmail.com>
 <Yt5Zn9cXDe9/F9RJ@kroah.com>
From:   Guenter Roeck <linux@roeck-us.net>
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On 7/25/22 01:51, Greg KH wrote:
> On Mon, Jul 25, 2022 at 04:06:05AM +0100, Alexey Klimov wrote:
>> +static bool nowayout = WATCHDOG_NOWAYOUT;
>> +module_param(nowayout, bool, 0);
>> +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
>> +			__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
>> +
> 
> Meta-comment about watchdog drivers, this is per-driver, not per-device,
> which does not make sense for when these devices are on removable busses
> where you can have multiple ones.
> 

It is really intended to be a system configuration parameter
(CONFIG_WATCHDOG_NOWAYOUT) which can be overridden. Also, I think it still
makes sense to have it, even for removable devices. The ability to bypass
the flag by pulling the device would defeat its purpose.

Guenter

> I don't suggest changing this (as it follows the current style of other
> watchdog drivers), but perhaps a sysfs attribute for watchdog devices
> can do the same thing in the future so you can do this on a per-device
> basis.
> 
> Anyway, driver looks good to me, nice work!
> 
> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>