Re: [PATCH AUTOSEL 6.6 02/17] x86/acpi: Ignore invalid x2APIC entries

[Thomas Gleixner]

On Tue, Dec 05 2023 at 23:04, Andres Freund wrote:
> On 2023-11-22 10:31:31 -0500, Sasha Levin wrote:
>> Currently, the kernel enumerates the possible CPUs by parsing both ACPI
>> MADT Local APIC entries and x2APIC entries. So CPUs with "valid" APIC IDs,
>> even if they have duplicated APIC IDs in Local APIC and x2APIC, are always
>> enumerated.
>
> As just described in
> https://lore.kernel.org/all/20231206065850.hs7k554v6wym7gw5@xxxxxxxxxxxxxxxxxx/
> and also previously described by John Sperbeck
> https://lore.kernel.org/all/20231122221947.781812-1-jsperbeck@xxxxxxxxxx/
>
> this patch causes some machines to "loose" cpus. All but one in my
> case.

Sorry for the delay.

> Even if the commit didn't have these unintended consequences, it seems like a
> commit like this hardly is -stable material?

Shit happens. We are all human, right?