Re: [PATCH net-next v3 2/2] net: plumb extack in __dev_change_net_namespace()

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Date: Thu, 20 Feb 2025 16:11:43 +0100
> Le 20/02/2025 à 14:24, Eric Dumazet a écrit :
> > On Thu, Feb 20, 2025 at 2:22 PM Nicolas Dichtel
> > <nicolas.dichtel@6wind.com> wrote:
> >>
> >> Le 20/02/2025 à 14:17, Eric Dumazet a écrit :
> >>> On Thu, Feb 20, 2025 at 2:03 PM Nicolas Dichtel
> >>> <nicolas.dichtel@6wind.com> wrote:
> >>>>
> >>>> It could be hard to understand why the netlink command fails. For example,
> >>>> if dev->netns_local is set, the error is "Invalid argument".
> >>>>
> >>>
> >>> After your patch, a new message is : "  "The interface has the 'netns
> >>> local' property""
> >>>
> >>> Honestly, I am not sure we export to user space the concept of 'netns local'
> >>>
> >>> "This interface netns is not allowed to be changed" or something like that ?
> >> Frankly, I was hesitating. I used 'netns local' to ease the link with the new
> >> netlink attribute, and with what was displayed by ethtool for a long time.
> >> I don't have a strong opinion about this.
> > 
> > No strong opinion either, I always have been confused by NETNS_LOCAL choice.
> Yes, it's not obvious. Maybe it could be renamed before exposing it to userspace
> via netlink.
> What about 'netns-locked'? Does someone have a better proposal?

Maybe NETNS_IMMUTABLE and netns-immutable ?
Then we can say "The interface netns is immutable" in extack.