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From:   "Tian, Kevin" <kevin.tian@intel.com>
To:     Jason Gunthorpe <jgg@nvidia.com>, "Liu, Yi L" <yi.l.liu@intel.com>
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Subject: RE: [RFC 03/20] vfio: Add vfio_[un]register_device()
Thread-Topic: [RFC 03/20] vfio: Add vfio_[un]register_device()
Thread-Index: AQHXrSFwNP3/pIcrZ0iM9X/cSoy0lKuuqYQAgACO5rA=
Date:   Wed, 22 Sep 2021 00:54:02 +0000
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References: <20210919063848.1476776-1-yi.l.liu@intel.com>
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> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Wednesday, September 22, 2021 12:01 AM
>=20
> >  One open about how to organize the device nodes under
> /dev/vfio/devices/.
> > This RFC adopts a simple policy by keeping a flat layout with mixed
> devname
> > from all kinds of devices. The prerequisite of this model is that devna=
mes
> > from different bus types are unique formats:
>=20
> This isn't reliable, the devname should just be vfio0, vfio1, etc
>=20
> The userspace can learn the correct major/minor by inspecting the
> sysfs.
>=20
> This whole concept should disappear into the prior patch that adds the
> struct device in the first place, and I think most of the code here
> can be deleted once the struct device is used properly.
>=20

Can you help elaborate above flow? This is one area where we need
more guidance.

When Qemu accepts an option "-device vfio-pci,host=3DDDDD:BB:DD.F",
how does Qemu identify which vifo0/1/... is associated with the specified=20
DDDD:BB:DD.F?=20

Thanks
Kevin