From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: [RFC PATCH 2/3] netdev: kernel-only IFF_HIDDEN netdevice
Date: Wed, 4 Apr 2018 20:20:51 +0200
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Wed, Apr 04, 2018 at 07:37:49PM CEST, davem@davemloft.net wrote:
>From: David Ahern <dsahern@gmail.com>
>Date: Wed, 4 Apr 2018 11:21:54 -0600
>
>> It is a netdev so there is no reason to have a separate ip command to
>> inspect it. 'ip link' is the right place.
>
>I agree on this.
>
>What I really don't understand still is the use case... really.
>
>So there are control netdevs, what exactly is the problem with that?
>
>Are we not exporting enough information for applications to handle
>these devices sanely?  If so, then's let add that information.
>
>We can set netdev->type to ETH_P_LINUXCONTROL or something like that.
>
>Another alternative is to add an interface flag like IFF_CONTROL or
>similar, and that probably is much nicer.
>
>Hiding the devices means that we acknowledge that applications are
>currently broken with control netdevs... and we want them to stay
>broken!
>
>That doesn't sound like a good plan to me.
>
>So let's fix handling of control netdevs instead of hiding them.

Exactly. Don't workaround userspace issues by kernel patches.