Re: [PATCH v13 6/6] PCI/DPC: Do not do recovery for hotplug enabled system

From: Sinan Kaya
Date: Mon Apr 16 2018 - 10:46:17 EST


On 4/15/2018 11:17 PM, Bjorn Helgaas wrote:
> It doesn't seem right to me that we handle both ERR_NONFATAL and
> ERR_FATAL events differently if we happen to have DPC support in a
> switch.
>
> Maybe we should consider triggering DPC only on ERR_FATAL? That would
> keep DPC out of the ERR_NONFATAL cases.
>
>From reliability perspective, it makes sense. DPC handles NONFATAL errors
by bringing down the link. If error happened behind a switch and root port
is handling DPC, we are impacting a lot of devices operation because of one
faulty device.

Keith, do you have any preference on this direction?

> For ERR_FATAL, maybe we should bite the bullet and use
> remove/re-enumerate for AER as well as for DPC. That would be painful
> for higher-level software, but if we're willing to accept that pain
> for new systems that support DPC, maybe life would be better overall
> if it worked the same way on systems without DPC?

Sure, we can go to this route as well.

--
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.