Re: [PATCH v2 net-next 06/14] net: Add per-netns netdev unregistration infra.

[Paolo Abeni <pabeni@redhat.com>]

On 7/3/26 2:09 AM, Kuniyuki Iwashima wrote:
> When we need to unregister a netdev in a different netns, we will
> delegate its unregistration to per-netns work.
> 
> There are three types of such cross-netns devices:
> 
>   1. Paired devices (e.g., netkit, veth, vxcan)
>      -> Unregistering one device also deletes its peer, which
>         may reside in another netns.
> 
>   2. Tunnel devices (e.g., bareudp, geneve, etc)
>      -> Destroying a netns removes devices in another netns if
>         their backend sockets reside in the dying netns
> 
>   3. Stacked devices (e.g., ipvlan, macvlan, etc)
>      -> Removing the lower device also removes multiple upper
>         devices, each of which may reside in different namespaces.
> 
> In these cases, we will use unregister_netdevice_queue_net() to
> queue such potential cross-netns devices for destruction.
> 
> Each driver must not call both unregister_netdevice_queue_net()
> and unregister_netdevice_queue() for the same device.  See the
> subsequent veth/bareudp/ipvlan patches for how they avoid double
> queueing.

Only if a repost is needed, possibly avoid the double negation above?

"""
Each driver must exactly call either unregister_netdevice_queue_net() or
unregister_netdevice_queue()...
"""

/P