From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <kubakici@wp.pl>
Subject: Re: [RFC] hv_netvsc: automatically name slave VF network device
Date: Tue, 19 Dec 2017 13:55:29 -0800
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Cc: netdev@vger.kernel.org, Stephen Hemminger <sthemmin@microsoft.com>,
        Jiri Pirko <jiri@resnulli.us>
To: Stephen Hemminger <stephen@networkplumber.org>
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On Tue, 19 Dec 2017 13:29:49 -0800, Stephen Hemminger wrote:
> > > biosdevname is dead, gone and wouldn't work on Azure (it dumpster
> > > dives in /dev/mem).    
> > 
> > Hm, I haven't worked on biosdevname myself, but AFAIU it also falls 
> > back to information from the PCI VPD, which could be populated by 
> > the hypervisor.  
> 
> VPD never had any useful standard are info.
> The rules used by udev come off sysfs, see:
>   https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/

Yes, the current VPD info looks quite limited, although it is
extendable.

> > > I assume you mean the modern application is udev, and it works
> > > but the name is meaningless because it based of synthetic PCI
> > > information. The PCI host adapter is simulated for pass through
> > > devices. Names like enp12s0.
> > > 
> > > Since every passthrough VF device on Hyper-V/Azure has a matching
> > > synthetic network device with same mac address. It is best to
> > > have the relationship shown in the name.    
> > 
> > How about we make the VF drivers expose "vf" as phys_port_name?
> > Then systemd/udev should glue that onto the name regardless of
> > how the VF is used.  
> 
> One of the goals was not to modify in any way other drivers (like VF).

Why?  Do you have out-of-tree drivers you can't change or some such?