From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gerd Hoffmann <kraxel@redhat.com>
Subject: Re: [RFC PATCH v1 1/1] vGPU core driver : to provide common
 interface for vGPU.
Date: Tue, 02 Feb 2016 09:29:18 +0100
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Cc: "Tian, Kevin" <kevin.tian@intel.com>,
	Kirti Wankhede <kwankhede@nvidia.com>,
	Alex Williamson <alex.williamson@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	"Ruan, Shuai" <shuai.ruan@intel.com>,
	"Song, Jike" <jike.song@intel.com>,
	"Lv, Zhiyuan" <zhiyuan.lv@intel.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	qemu-devel <qemu-devel@nongnu.org>
To: Neo Jia <cjia@nvidia.com>
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On Di, 2016-02-02 at 00:13 -0800, Neo Jia wrote:
> On Tue, Feb 02, 2016 at 09:00:43AM +0100, Gerd Hoffmann wrote:
> >   Hi,
> > 
> > > And for UUID, I remember Alex had a concern on using it in kernel. 
> > > Honestly speaking I don't have a good idea here. In Xen side there is a VM ID
> > > which can be easily used as the index. But for KVM, what would be the best
> > > identifier to associate with a VM?
> > 
> > The vgpu code doesn't need to associate the vgpu device with a vm in the
> > first place.  You get all guest address space information from qemu, via
> > vfio iommu interface.
> > 
> > When qemu does't use kvm (tcg mode), things should still work fine.
> > Using vfio-based vgpu devices with non-qemu apps (some kind of test
> > suite for example) should work fine too.
> 
> Hi Gerd and Kevin,
> 
> I thought Alex had agreed with the UUID as long as it is not tied with VM,
> probably it is just his comment gets lost in our previous long email thread.

As long as it isn't tied to a VM it is fine indeed.  We'll need names
for the devices, and using a uuid certainly is one option.  Could also
be a simple "vgpu${index}".  A more descriptive name such as
"nvidia-grid-${index}" or "igd-skl-${index}".  Or just a free-form
string where the driver can fill whatever it wants (including a uuid).

cheers,
  Gerd