From mboxrd@z Thu Jan  1 00:00:00 1970
From: timur@codeaurora.org (Timur Tabi)
Date: Wed, 4 May 2016 11:17:29 -0500
Subject: [PATCH RFC] Watchdog: sbsa_gwdt: Enhance timeout range
In-Reply-To: <20160504155932.GH13045@dhcppc6.redhat.com>
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 <5728BEC4.6050603@codeaurora.org> <20160503155141.GF13045@dhcppc6.redhat.com>
 <20160503171602.GA2518@roeck-us.net>
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 <20160504155932.GH13045@dhcppc6.redhat.com>
Message-ID: <572A2099.4070901@codeaurora.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Pratyush Anand wrote:
> Its unique to SBSA because you have very little timeout here. kexec-tools
> upstream does not have any mechanism to handle watchdog timeout. Lets say even
> if we implement a framework there, the best it can do is to ping the watchdog
> again.

Ok, so it's more accurate to say that kexec has a minimum watchdog 
timeout requirement.  What happens if the system admin sets the timeout 
to 5 seconds arbitrarily?  The system will reset during kexec, no matter 
which hardware is used.

This still sounds like a band-aid to me.  We're just assuming that we 
need a timeout of at least 20 seconds to support kexec.  Frankly, this 
still sounds like a problem the kexec developers needs to acknowledge 
and deal with.

Still I'm okay with a patch that extends the timeout by programming WCV, 
but it has to be commented as a hack specifically to support kexec 
because the timeout might be too short.  Then Wim can decide whether he 
supports such changes.

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