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Date:   Sun, 7 Jul 2019 21:44:00 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Pingfan Liu <kernelfans@gmail.com>
cc:     x86@kernel.org, Michal Hocko <mhocko@suse.com>,
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Subject: Re: [PATCH 2/2] x86/numa: instance all parsed numa node
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On Fri, 5 Jul 2019, Pingfan Liu wrote:

> I hit a bug on an AMD machine, with kexec -l nr_cpus=4 option. nr_cpus option
> is used to speed up kdump process, so it is not a rare case.

But fundamentally wrong, really.

The rest of the CPUs are in a half baken state and any broadcast event,
e.g. MCE or a stray IPI, will result in a undiagnosable crash.

Thanks,

	tglx