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Date: Mon, 4 Sep 2017 14:10:50 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
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        Sebastian Siewior <bigeasy@linutronix.de>,
        Nicholas Piggin <npiggin@gmail.com>, Don Zickus <dzickus@redhat.com>,
        Chris Metcalf <cmetcalf@mellanox.com>
Subject: Re: [patch 11/29] lockup_detector: Remove park_in_progress hackery
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On Mon, Sep 04, 2017 at 01:09:06PM +0200, Ulrich Obergfell wrote:

> - A thread hogs CPU N (soft lockup) so that watchdog/N is unable to run.
> - A user re-configures 'watchdog_thresh' on the fly. The reconfiguration
>   requires parking/unparking of all watchdog threads.

This is where you fail, its silly to require parking for
reconfiguration.