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Date:   Mon, 2 Nov 2020 14:26:32 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Dave Jiang <dave.jiang@intel.com>
CC:     "Raj, Ashok" <ashok.raj@intel.com>,
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Subject: Re: [PATCH v4 00/17] Add VFIO mediated device support and DEV-MSI
 support for the idxd driver
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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