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Date: Fri, 18 Dec 2015 18:14:12 +0000
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: Guenter Roeck <linux@roeck-us.net>
Cc: Tomas Winkler <tomas.winkler@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Wim Van Sebroeck <wim@iguana.be>,
        Alexander Usyskin <alexander.usyskin@intel.com>,
        linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [char-misc-next v2 7/7] watchdog: mei_wdt: re-register device
 on event
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> > That breaks the existing behaviour of hot pluggable watchdog interfaces
> > and is different to just about any other device in the kernel. Today with
> > any desktop or server distribution you can already trivially arrange for
> > watchdog daemons to start at the point a watchdog is detected dynamically.
> >
> 
> Ok, you have a point. Wonder if any distributions are doing that, though.
> Any idea ?

I don't know for any of the out of the box mainstream ones.

There is a second problem if you register the watchdog but don't actually
have it enabled. Consider the case where a user has the mei watchdog
disabled and a more advanced watchdog card plugged in - in that case the
naïvely implemented existing watchdog app may bind to the non-functional
watchdog, not the correct one.

Alan