linux-kernel - linux-3.7.1: disable and reenable NMI watchdog => panic

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Date:	Sun, 6 Jan 2013 23:44:03 +0600
From:	"Alexander E. Patrakov" <patrakov@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: linux-3.7.1: disable and reenable NMI watchdog => panic

Hi.

As illustrated by the attached screen photo (sorry for bad quality),
disabling and then reenabling the NMI watchdog panics the kernel
(3.7.1). This is reproducible in qemu-kvm as well, but I could not get
the nice panic message to pop up there (most of the time, it just
locks up). This bug is rather important, as laptop-mode-tools, by
default, try to reenable this NMI watchdog when AC power appears, and
this is how I caught the bug the first time.

-- 
Alexander E. Patrakov

Download attachment "KernelPanic.jpg" of type "image/jpeg" (37328 bytes)