Re: [PATCH 3/3] mce: acpi/apei: trace: Enable ghes memory error trace event

Borislav Petkov
2013-08-15T13:51:11Z

On Thu, Aug 15, 2013 at 10:34:21AM -0300, Mauro Carvalho Chehab wrote:
> Yes, but the thing is that it is not safe to use the hardware driver
> if the BIOS is also reading the hardware error registers directly, as,
> on several hardware, a read cause the error data to be cleaned on such
> register.

Here's the deal:

* We parse some APEI table and disable those MCA banks which the BIOS
wants to handle first.

* When the BIOS decides to report an error from that handling, it does
so over another BIOS table.

* Now you have two possibilities:

** On systems without an edac driver or where it doesn't make sense to
have the ghes_edac driver, we call trace_mc_event() straight from APEI
code (this is what we're currently discussung).

** On other systems, where we need ghes_edac, we *don't* use the
trace_mc_event() tracepoint in the APEI code but let it come from
ghes_edac with additional information collected by edac.

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
--