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Date:   Thu, 11 Feb 2021 08:47:03 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Alex Williamson <alex.williamson@redhat.com>,
        Max Gurtovoy <mgurtovoy@nvidia.com>,
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        cjia@nvidia.com, yishaih@nvidia.com, aik@ozlabs.ru
Subject: Re: [PATCH 8/9] vfio/pci: use x86 naming instead of igd
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On Wed, Feb 03, 2021 at 09:54:48AM -0400, Jason Gunthorpe wrote:
> If people are accepting that these device-specific drivers are
> required then we need to come to a community consensus to decide what
> direction to pursue:
> 
> * Do we embrace the driver core and use it to load VFIO modules like a
>   normal subsytem (this RFC)
> 
> OR 
> 
> * Do we make a driver-core like thing inside the VFIO bus drivers and
>   have them run their own special driver matching, binding, and loading
>   scheme. (May RFC)
> 
> Haven't heard a 3rd option yet..

The third option would be to use the driver core to bind the VFIO
submodules.  Define a new bus for it, which also uses the normal PCI IDs
for binding, and walk through those VFIO specific drivers when vfio_pci
is bound to a device.  That would provide a pretty clean abstraction
and could even keep the existing behavior of say bind to all VGA devices
with an Intel vendor ID (even if I think that is a bad idea).