Re: [PATCH v2 3/3] acpi/apei: Add NVIDIA GHES vendor CPER record handler

["Kai-Heng Feng" <kaihengf@nvidia.com>]

On Wed Mar 25, 2026 at 12:15 AM CST, Bjorn Helgaas wrote:
> External email: Use caution opening links or attachments
>
>
> On Tue, Mar 24, 2026 at 05:33:06PM +0800, Kai-Heng Feng wrote:
>> On 2026-03-20 09:52, Bjorn Helgaas wrote:
>> > On Thu, Mar 19, 2026 at 07:13:09PM +0800, Kai-Heng Feng wrote:
>> > > Add support for decoding NVIDIA-specific CPER sections delivered via
>> > > the APEI GHES vendor record notifier chain. NVIDIA hardware generates
>> > > vendor-specific CPER sections containing error signatures and diagnostic
>> > > register dumps. This implementation registers a notifier_block with the
>> > > GHES vendor record notifier and decodes these sections, printing error
>> > > details via dev_info().
>> > >
>> > > The driver binds to ACPI device NVDA2012, present on NVIDIA server
>> > > platforms. The NVIDIA CPER section contains a fixed header with error
>> > > metadata (signature, error type, severity, socket) followed by
>> > > variable-length register address-value pairs for hardware diagnostics.
>> > >
>> > > This work is based on libcper [0].
>> > >
>> > > Example output:
>> > > nvidia-ghes NVDA2012:00: NVIDIA CPER section, error_data_length: 544
>> > > nvidia-ghes NVDA2012:00: signature: CMET-INFO
>> > > nvidia-ghes NVDA2012:00: error_type: 0
>> > > nvidia-ghes NVDA2012:00: error_instance: 0
>> > > nvidia-ghes NVDA2012:00: severity: 3
>> > > nvidia-ghes NVDA2012:00: socket: 0
>> > > nvidia-ghes NVDA2012:00: number_regs: 32
>> > > nvidia-ghes NVDA2012:00: instance_base: 0x0000000000000000
>> > > nvidia-ghes NVDA2012:00: register[0]: address=0x8000000100000000 value=0x0000000100000000
>> >
>> > Is there a convenient way to connect NVDA2012:00 with the actual
>> > device?  I assume this is typically a PCIe device?  How would we
>> > relate this with PCIe errors?
>>
>> The CPER report is from ARM RAS firmware and not neccessarily be
>> related to a PCIe device.
>
> Right, I know CPER is more general than just PCI/PCIe.
>
> But in this case, I think NVDA2012 probably *is* a PCIe device.  How
> would we figure out which one?  If we have to manually do an acpidump,
> figure out which NVDA2012 is :00, and look for an _ADR or something,
> that doesn't really seem convenient for multi-NVDA2012 situations.

It's actually just an ACPI device:
Device (CPER)
{
  Name (_HID, "NVDA2012")  // _HID: Hardware ID
  Name (_UID, 0x00)  // _UID: Unique ID
  Method (_DSM, 4, Serialized) // _DSM: Device-Specific Method
}

And that's it.