Re: [PATCH v4 3/3] PCI/AER: Report fatal errors of RCiEP and EP if link recoverd

[Shuai Xue]

在 2025/3/3 12:33, Shuai Xue 写道:
> 在 2025/3/3 11:43, Sathyanarayanan Kuppuswamy 写道:
> > On 2/16/25 6:42 PM, Shuai Xue wrote:
> > > The AER driver has historically avoided reading the configuration space of
> > > an endpoint or RCiEP that reported a fatal error, considering the link to
> > > that device unreliable. Consequently, when a fatal error occurs, the AER
> > > and DPC drivers do not report specific error types, resulting in logs like:
> > >
> > >    pcieport 0000:30:03.0: EDR: EDR event received
> > >    pcieport 0000:30:03.0: DPC: containment event, status:0x0005 source:0x3400
> > >    pcieport 0000:30:03.0: DPC: ERR_FATAL detected
> > >    pcieport 0000:30:03.0: AER: broadcast error_detected message
> > >    nvme nvme0: frozen state error detected, reset controller
> > >    nvme 0000:34:00.0: ready 0ms after DPC
> > >    pcieport 0000:30:03.0: AER: broadcast slot_reset message
> > >
> > > AER status registers are sticky and Write-1-to-clear. If the link recovered
> > > after hot reset, we can still safely access AER status of the error device.
> > > In such case, report fatal errors which helps to figure out the error root
> > > case.
> > >
> > > After this patch, the logs like:
> > >
> > >    pcieport 0000:30:03.0: EDR: EDR event received
> > >    pcieport 0000:30:03.0: DPC: containment event, status:0x0005 source:0x3400
> > >    pcieport 0000:30:03.0: DPC: ERR_FATAL detected
> > >    pcieport 0000:30:03.0: AER: broadcast error_detected message
> > >    nvme nvme0: frozen state error detected, reset controller
> > >    pcieport 0000:30:03.0: waiting 100 ms for downstream link, after activation
> > >    nvme 0000:34:00.0: ready 0ms after DPC
> > >    nvme 0000:34:00.0: PCIe Bus Error: severity=Uncorrectable (Fatal), type=Data Link Layer, (Receiver ID)
> > >    nvme 0000:34:00.0:   device [144d:a804] error status/mask=00000010/00504000
> > >    nvme 0000:34:00.0:    [ 4] DLP                    (First)
> > >    pcieport 0000:30:03.0: AER: broadcast slot_reset message
> >
> > IMO, above info about device error details is more of a debug info. Since the
> > main use of this info use to understand more details about the recovered
> > DPC error. So I think is better to print with debug tag. Lets see what others
> > think.
> >
> > Code wise, looks fine to me.
>
> thanks, looking forward to more feedback.
> >

Hi, all,

Gentle ping.

Thanks.
Shuai