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Subject: Re: WARNING: at arch/x86/kernel/smp.c:119
 native_smp_send_reschedule+0x25/0x43()
From: Peter Zijlstra <peterz@infradead.org>
To: Don Zickus <dzickus@redhat.com>
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        Sasha Levin <levinsasha928@gmail.com>, Josh Boyer <jwboyer@gmail.com>,
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Date: Fri, 10 Feb 2012 21:36:03 +0100
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On Fri, 2012-02-10 at 15:31 -0500, Don Zickus wrote:
> So my second patch which I will eventually post will just skip the WARN_ON
> if the system is going down.  Not sure if that is the proper way to address
> this problem or change all of the stop_this_cpu code to use a different
> bitmask than the cpu_online bitmask (but then you run the risk of a stuck
> IPI I guess if the cpu is halted without notifying anyone). 

Yeah, the async hard kill of all cpus is bound to make problems.. what
I'm wondering is, why is this in the normal shutdown path and not
specific to a hard panic?

Trying to make this work is just not going to be pretty, and in the
panic case we really don't care much.