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Date: Mon, 5 Jan 2015 16:14:12 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Kiran Raparthy <kiran.kumar@linaro.org>
Cc: linux-kernel@vger.kernel.org, Colin Cross <ccross@android.com>,
        Jason Wessel <jason.wessel@windriver.com>,
        kgdb-bugreport@lists.sourceforge.net,
        Android Kernel Team <kernel-team@android.com>,
        John Stultz <john.stultz@linaro.org>,
        Sumit Semwal <sumit.semwal@linaro.org>
Subject: Re: [RFC v4] debug: prevent entering debug mode on panic/exception.
Message-Id: <20150105161412.44f53313e1d771dc9f968264@linux-foundation.org>
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References: <1419338309-16729-1-git-send-email-kiran.kumar@linaro.org>
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On Tue, 23 Dec 2014 18:08:29 +0530 Kiran Raparthy <kiran.kumar@linaro.org> wrote:

> From: Colin Cross <ccross@android.com>
> 
> debug: prevent entering debug mode on panic/exception.
> 
> On non-developer devices, kgdb prevents the device from rebooting
> after a panic.
> 
> Incase of panics and exceptions, to allow the device to reboot, prevent
> entering debug mode to avoid getting stuck waiting for the user to interact
> with debugger.
> 
> To avoid entering the debugger on panic/exception without any extra
> configuration, panic_timeout is being used which can be set via
> /proc/sys/kernel/panic at run time and CONFIG_PANIC_TIMEOUT sets the default
> value.
> 
> ...
>

hm.  Why overload the meaning of panic_timeout in this fashion?  If
someone is using kgdb and has panic_timeout set, they'll get quiet a
surprise.

Would it be cleaner/clearer to add some new standalone control for
this?  One which is only present if CONFIG_KGDB.


We appear to have forgotten to document panic_timeout.  Sigh.