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

Naveen N. Rao
2013-08-13T17:18:01Z

On 08/13/2013 06:11 PM, Mauro Carvalho Chehab wrote:
> Em Tue, 13 Aug 2013 17:11:18 +0530
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> escreveu:
>
>> On 08/12/2013 08:14 PM, Mauro Carvalho Chehab wrote:
>>>> But, this only seems to expose the APEI data as a string
>>>> and doesn't look to really make all the fields available to user-space
>>>> in a raw manner. Not sure how well this can be utilised by a user-space
>>>> tool. Do you have suggestions on how we can do this?
>>>
>>> There's already an userspace tool that handes it:
>>> https://git.fedorahosted.org/cgit/rasdaemon.git/
>>>
>>> What is missing there on the current version is the bits that would allow
>>> to translate from APEI way to report an error (memory node, card, module,
>>> bank, device) into a DIMM label[1].
>>
>> If I'm reading this right, all APEI data seems to be squashed into a
>> string in mc_event.
>
> Yes. We had lots of discussion about how to map memory errors over the
> last couple years. Basically, it was decided that the information that
> could be decoded into a DIMM to be mapped as integers, and all other
> driver-specific data to be added as strings.
>
> On the tests I did, different machines/vendors fill the APEI data on
> a different way, with makes harder to associate them to a DIMM.

Ok, so it looks like ghes_edac isn't quite useful yet.

In the meantime, like Boris suggests, I think we can have a different
trace event for raw APEI reports - userspace can use it as it pleases.

Once ghes_edac gets better, users can decide whether they want raw APEI
reports or the EDAC-processed version and choose one or the other trace
event.

Regards,
Naveen