Re: [PATCH v13 7/7] x86/crash: add x86 crash hotplug support

[Borislav Petkov]

On Wed, Nov 02, 2022 at 11:54:08AM -0500, Eric DeVolder wrote:
> Technically the answer is no; cpu hotplug events are independent of memory
> hotplug events, but both are written into the elfcorehdr, so in reality
> yes... The elfcorehdr contains a single list of Phdrs describing CPUs and
> crash memory ranges; the entire list is re-written on a hotplug change.

Then technically also yes. Otherwise your crash information will contain
wrong CPU numbers.

How has that not been a problem until now...?

I.e., offline a bunch of CPUs and then cause a crash dump.

Hmm.

-- 
Regards/Gruss,
    Boris.

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