Re: [PATCH 3/3] x86/mce: Use mce_prep_record() helpers for apei_smca_report_x86_error()

From: Borislav Petkov
Date: Wed May 29 2024 - 13:28:37 EST


On Tue, May 21, 2024 at 07:54:34AM -0500, Yazen Ghannam wrote:
> Current AMD systems can report MCA errors using the ACPI Boot Error
> Record Table (BERT). The BERT entries for MCA errors will be an x86
> Common Platform Error Record (CPER) with an MSR register context that
> matches the MCAX/SMCA register space.
>
> However, the BERT will not necessarily be processed on the CPU that
> reported the MCA errors. Therefore, the correct CPU number needs to be
> determined and the information saved in struct mce.
>
> The CPU number is determined by searching all possible CPUs for a Local
> APIC ID matching the value in the x86 CPER.

You're explaining the code again. :)

> for_each_possible_cpu(cpu) {
> - if (cpu_data(cpu).topo.initial_apicid == lapic_id) {
> - m.extcpu = cpu;
> - m.socketid = cpu_data(m.extcpu).topo.pkg_id;
> + if (cpu_data(cpu).topo.initial_apicid == lapic_id)
> break;
> - }
> }
>
> - m.apicid = lapic_id;
> + if (!cpu_possible(cpu))
> + return -EINVAL;

What's that test for? You just iterated over the possible CPUs using
"cpu" as the iterator there...

--
Regards/Gruss,
Boris.

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