Re: PROBLEM: CPU hotplug leads to NULL pointer dereference with RAPL enabled on AMD 2990WX

From: Borislav Petkov
Date: Mon Jan 04 2021 - 04:50:55 EST


On Mon, Jan 04, 2021 at 12:02:44AM +0100, Johnathan Smithinovic wrote:
> CPU hotplug leads to NULL pointer dereference with RAPL enabled on AMD 2990WX
>
>
> When hot-plugging CPUs (e.g. manually or on suspend) I get a NULL
> pointer dereference in rapl_cpu_offline() for CPUs 16 and 24.
> It *seems* to me that this has to do with commit
> 700d098acec5271161606f3c0086b71695ea2ef8
> ("x86/CPU/AMD: Save AMD NodeId as cpu_die_id").
> When reverting said commit hotplug works again.

Yeah, known issue and I'm working on it.

Thx for reporting.

--
Regards/Gruss,
Boris.

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