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Subject: Re: [Qemu-devel] [RFC PATCH v1 1/1] vGPU core driver : to provide
 common interface for vGPU.
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To: Gerd Hoffmann <kraxel@redhat.com>
Cc: "Ruan, Shuai" <shuai.ruan@intel.com>, "Song,
	Jike" <jike.song@intel.com>, "kvm@vger.kernel.org" <kvm@vger.kernel.org>, "Tian, Kevin" <kevin.tian@intel.com>, Kirti Wankhede <kwankhede@nvidia.com>, qemu-devel <qemu-devel@nongnu.org>, Alex Williamson <alex.williamson@redhat.com>, "Lv,
	Zhiyuan" <zhiyuan.lv@intel.com>, Paolo Bonzini <pbonzini@redhat.com>

On Wed, Feb 17, 2016 at 07:52:53AM +0100, Gerd Hoffmann wrote:
>   Hi,
> 
> > The answer is simple, having a UUID as part of the device name will give you a
> > unique sysfs path that will be opened by QEMU.
> 
> A descriptive name will work too, and I think it'll be easier to make
> those names persistent because you don't have to store the uuids
> somewhere to re-create the same setup afer reboot.

Hi Gerd,

Right, UUID will be persistent cross reboot. The qemu vgpu path for a given VM will 
not get changed when it gets reboots and multiple other devices have been
created in the middle.

> 
> > If you are worried about losing meaningful name here, we can create a sysfs file
> > to capture the vendor device description if you like.
> 
> You can also store the uuid in a sysfs file ...

Another benefit is that having the UUID as part of the virtual vgpu device path will
allow whoever is going to config the QEMU to automatically discover the virtual
device sysfs for free.

Thanks,
Neo

> 
> cheers,
>   Gerd
>