Re: [PATCH v2 1/2] Replace if statement with WARN_ON_ONCE() in cmci_rediscover().

[Tang Chen]

On 10/22/2012 06:14 PM, Borislav Petkov wrote:
> On Mon, Oct 22, 2012 at 10:10:24AM +0800, Tang Chen wrote:
> > I don't why before we just jumped over it. But I think if we have an
> > online cpu == dying here, it must be wrong. So I think we should warn
> > it, not just jump over it.
>
> Why do we need to warn? What good would that bring us?
>
> AFAICT, the check in cmci_rediscover is there to make sure we absolutely
> don't rediscover on the dying cpu. I think it is a safety precaution in
> concurrency scenarios between cpu hotplug and mce code.

Hi Borislav,

As I said, cmci_rediscover() is only used to handle CPU_POST_DEAD event.
And is uses for_each_online_cpu to iterate all online cpus. If we get a
online cpu == dying, I think we are in a wrong situation. I think at
least, we should give a warning.

Thanks. :)

> Thanks.

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