Re: WARNING: at arch/x86/kernel/smp.c:119native_smp_send_reschedule+0x25/0x43()

From: Don Zickus
Date: Fri Feb 10 2012 - 16:04:44 EST


On Fri, Feb 10, 2012 at 09:36:03PM +0100, Peter Zijlstra wrote:
> 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?

I didn't write the original code, I just changed it from REBOOT_IRQ to
NMI and left all the stop_this_cpu stuff alone.

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

Sure.

Cheers,
Don
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