Re: [PATCH v6] vfio error recovery: kernel support

Michael S. Tsirkin
2017-04-05T22:36:41Z

On Wed, Apr 05, 2017 at 04:19:10PM -0600, Alex Williamson wrote:
> On Thu, 6 Apr 2017 00:50:22 +0300
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
>
> > On Wed, Apr 05, 2017 at 01:38:22PM -0600, Alex Williamson wrote:
> > > The previous intention of trying to handle all sorts of AER faults
> > > clearly had more value, though even there the implementation and
> > > configuration requirements restricted the practicality. For instance
> > > is AER support actually useful to a customer if it requires all ports
> > > of a multifunction device assigned to the VM? This seems more like a
> > > feature targeting whole system partitioning rather than general VM
> > > device assignment use cases. Maybe that's ok, but it should be a clear
> > > design decision.
> >
> > Alex, what kind of testing do you expect to be necessary?
> > Would you say testing on real hardware and making it trigger
> > AER errors is a requirement?
>
> Testing various fatal, non-fatal, and corrected errors with aer-inject,
> especially in multfunction configurations (where more than one port
> is actually usable) would certainly be required. If we have cases where
> the driver for a companion function can escalate a non-fatal error to a
> bus reset, that should be tested, even if it requires temporary hacks to
> the host driver for the companion function to trigger that case. AER
> handling is not something that the typical user is going to experience,
> so it should to be thoroughly tested to make sure it works when needed
> or there's little point to doing it at all. Thanks,
>
> Alex

Some things can be tested within a VM. What would you
say would be sufficient on a VM and what has to be
tested on bare metal?

--
MST