Re: [PATCH 0/2] efi/cper, cxl: Decode CXL Protocol Errors CPER

Smita Koralahalli
2022-10-26T19:31:42Z

On 10/25/2022 5:11 PM, Dan Williams wrote:
> Smita Koralahalli wrote:
>> Hi Dan,
>>
>> On 10/21/2022 3:18 PM, Dan Williams wrote:
>>> Hi Smita,
>>>
>>> Smita Koralahalli wrote:
>>>> This series adds decoding for the CXL Protocol Errors Common Platform
>>>> Error Record.
>>> Be sure to copy Ard Biesheuvel <ardb@kernel.org>, added, on
>>> drivers/firmware/efi/ patches.
>>>
>>> Along those lines, drivers/cxl/ developers have an idea of what is
>>> contained in the new CXL protocol error records and why Linux might want
>>> to decode them, others from outside drivers/cxl/ might not. It always
>>> helps to have a small summary of the benefit to end users of the
>>> motivation to apply a patch set.
>> Sure, will include in my v2.
>>
>>>> Smita Koralahalli (2):
>>>> efi/cper, cxl: Decode CXL Protocol Error Section
>>>> efi/cper, cxl: Decode CXL Error Log
>>>>
>>>> drivers/firmware/efi/Makefile | 2 +-
>>>> drivers/firmware/efi/cper.c | 9 +++
>>>> drivers/firmware/efi/cper_cxl.c | 108 ++++++++++++++++++++++++++++++++
>>>> drivers/firmware/efi/cper_cxl.h | 58 +++++++++++++++++
>>>> include/linux/cxl_err.h | 21 +++++++
>>>> 5 files changed, 197 insertions(+), 1 deletion(-)
>>> I notice no updates for the trace events in ghes_do_proc(), is that next
>>> in your queue? That's ok to be a follow-on after v2.
>> Sorry, if I haven't understood this right. Are you implying about the
>> "handling"
>> of cxl memory errors in ghes_do_proc() or is it just copying of CPER
>> entries to
>> tracepoints?
> Right now ghes_do_proc() will let the CXL CPER records fall through to
> log_non_standard_event(). Are you planning to add trace event decode
> there for CPER_SEC_CXL_PROT_ERR records?

Thanks! Yeah its a good idea to add. I did not think about this before.
I will send this as a separate patchset after v2.

I think with this cxl cper trace event support and Ira's patchset which
traces
specific event record types via Get Event Record, we can start the userspace
handling probably in rasdaemon?

>
> I am not sure if the CXL CPER to trace record conversion belongs there,
> or somewhere closer to trace_aer_event() invocations since the CXL
> protocol errors are effectively an extenstion of PCI AER events.

Right, I will keep it simple in v1 and get the comments about the
placement..

Thanks,
Smita