From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [RFC PATCH 2/3] netdev: kernel-only IFF_HIDDEN netdevice
Date: Tue, 3 Apr 2018 19:04:26 -0600
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Cc: Si-Wei Liu <si-wei.liu@oracle.com>, mst@redhat.com,
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To: Jiri Pirko <jiri@resnulli.us>
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On 4/3/18 9:42 AM, Jiri Pirko wrote:
>>
>> There are other use cases that want to hide a device from userspace. I
> 
> What usecases do you have in mind?

As mentioned in a previous response some kernel drivers create control
netdevs. Just as in this case users should not be mucking with it, and
S/W like lldpd should ignore it.

> 
>> would prefer a better solution than playing games with name prefixes and
>> one that includes an API for users to list all devices -- even ones
>> hidden by default.
> 
> Netdevice hiding feels a bit scarry for me. This smells like a workaround
> for userspace issues. Why can't the netdevice be visible always and
> userspace would know what is it and what should it do with it?
> 
> Once we start with hiding, there are other things related to that which
> appear. Like who can see what, levels of visibility etc...
> 

I would not advocate for any API that does not allow users to have full
introspection. The intent is to hide the netdev by default but have an
option to see it.