Re: [PATCH v4 00/17] Add VFIO mediated device support and DEV-MSI support for the idxd driver

From: Jason Gunthorpe
Date: Mon Nov 02 2020 - 13:26:44 EST


On Mon, Nov 02, 2020 at 11:18:33AM -0700, Dave Jiang wrote:
>
>
> On 11/2/2020 10:19 AM, Jason Gunthorpe wrote:
> > On Mon, Nov 02, 2020 at 08:20:43AM -0800, Raj, Ashok wrote:
> > > Creating these private interfaces for intra-module are just 1-1 and not
> > > general purpose and every accelerator needs to create these instances.
> >
> > This is where we are going, auxillary bus should be merged soon which
> > is specifically to connect these kinds of devices across subsystems
>
> I think this resolves the aux device probe/remove issue via a common bus.
> But it does not help with the mdev device needing a lot of the device
> handling calls from the parent driver as it share the same handling as the
> parent device.

The intention of auxiliary bus is that the two parts will tightly
couple across some exported function interface.

> My plan is to export all the needed call via EXPORT_SYMBOL_NS() so
> the calls can be shared in its own namespace between the modules. Do
> you have any objection with that?

I think you will be the first to use the namespace stuff for this, it
seems like a good idea and others should probably do so as well.

Jason