Re: [PATCH 07/14] cxl: Add support for using the kernel API with a real PHB

[Ian Munsie <imunsie@au1.ibm.com>]

Excerpts from Frederic Barrat's message of 2016-07-06 20:30:41 +0200:
> 
> > @@ -1572,6 +1575,9 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev,
> >            */
> >           for (i = 0; i < adapter->slices; i++) {
> >               afu = adapter->afu[i];
> > +            /* Only participate in EEH if we are on a virtual PHB */
> > +            if (afu->phb == NULL)
> > +                return PCI_ERS_RESULT_NONE;
> >               cxl_vphb_error_detected(afu, state);
> >           }
> 
> 
> Sorry, I had my notes out of order, something is bugging me here. Don't 
> we always define afu->phb, though for Mellanox (or if there's no config 
> record in the general case), we don't have any devices attached to it?

I think you're right. I'll change the vPHB code to skip it if there are
no configuration records.

> Which raises the question of the handling of slot_reset and resume 
> callbacks...

We aren't going to support EEH (at least not yet) - the vPHB model makes
this (relatively) easy since we can notify the AFU drivers when we get
notified, but in the peer model it will be the real PHB notifying us and
the networking drivers. If we do end up supporting that, it will come
later.

Cheers,
-Ian