Re: [PATCH v7] x86/mce: retrieve poison range from hardware

Borislav Petkov
2022-08-26T18:09:20Z

On Fri, Aug 26, 2022 at 10:54:31AM -0700, Dan Williams wrote:
> How about:
>
> ---
>
> When memory poison consumption machine checks fire,
> mce-notifier-handlers like nfit_handle_mce() record the impacted
> physical address range.

... which is reported by the hardware in the MCi_MISC MSR.

> The error information includes data about blast
> radius, i.e. how many cachelines did the hardware determine are
> impacted.

Yap, nice.

> A recent change, commit 7917f9cdb503 ("acpi/nfit: rely on
> mce->misc to determine poison granularity"), updated nfit_handle_mce()
> to stop hard coding the blast radius value of 1 cacheline, and instead
> rely on the blast radius reported in 'struct mce' which can be up to 4K
> (64 cachelines).
>
> It turns out that apei_mce_report_mem_error() had a similar problem in
> that it hard coded a blast radius of 4K rather than checking the blast

s/checking/reading/

> radius in the error information. Fix apei_mce_report_mem_error() to

s/in/from/

> convey the proper poison granularity.
>
> ---

Yap, that's a lot better.

Thanks!

--
Regards/Gruss,
Boris.