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

Naveen N. Rao
2013-08-13T16:56:23Z

On 08/13/2013 05:51 PM, Mauro Carvalho Chehab wrote:
> Em Tue, 13 Aug 2013 17:06:14 +0530
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> escreveu:
>
>> On 08/12/2013 11:26 PM, Borislav Petkov wrote:
>>> On Mon, Aug 12, 2013 at 02:25:57PM -0300, Mauro Carvalho Chehab wrote:
>>>> Userspace still needs the EDAC sysfs, in order to identify how the
>>>> memory is organized, and do the proper memory labels association.
>>>>
>>>> What edac_ghes does is to fill those sysfs nodes, and to call the
>>>> existing tracing to report errors.
>>
>> I suppose you're referring to the entries under /sys/devices/system/edac/mc?
>
> Yes.
>
>>
>> I'm not sure I understand how this helps. ghes_edac seems to just be
>> populating this based on dmi, which if I'm not mistaken, can be obtained
>> in userspace (mcelog as an example).
>>
>> Also, on my system, all DIMMs are being reported under mc0. I doubt if
>> the labels there are accurate.
>
> Yes, this is the current status of ghes_edac, where BIOS doesn't provide any
> reliable way to associate a given APEI report to a physical DIMM slot label.
>
> The plan is to add more logic there as BIOSes start to provide some reliable
> way to do such association. I discussed this subject with a few vendors
> while I was working at Red Hat.

Hmm... is there anything specific in the APEI report that could help?
More importantly, is there a need to do this in-kernel rather than in
user-space?

Thanks,
Naveen