Re: Configuration vs. compat hints [was Re: [Qemu-devel] [PATCHv3 03/13] qemu: add routines to manage PCI capabilities]

[Avi Kivity]

On 06/16/2009 09:32 PM, Jamie Lokier wrote:
> Avi Kivity wrote:
>    
> > Another issue is enumeration.  Guests will present their devices in the
> > order they find them on the pci bus (of course enumeration is guest
> > specific).  So if I have 2 virtio controllers the only way I can
> > distinguish between them is using their pci slots.
> >      
>
> virtio controllers really should have a user-suppliable string or UUID
> to identify them to the guest.  Don't they?
>    

virtio controllers don't exist.  When they do, they may have a UUID or 
not, but in either case guest infrastructure is in place for reporting 
the PCI slot, not the UUID.

virtio disks do have a UUID.  I don't think older versions of Windows 
will use it though, so if you reorder your slots you'll see your drive 
letters change.  Same with Linux if you don't use udev by-uuid rules.

--
Do not meddle in the internals of kernels, for they are subtle and quick to 
panic.