The biggest blocker to per-netns RTNL is netdev unregistration.
It starts within a single netns (e.g., during a device lookup or
netns dismantle), but it can eventually involve multiple namespaces,
such as when upper ipvlan devices reside in different netns.
This prevents us from acquiring multiple rtnl_net_lock()s beforehand.
When we encounter such a cross-netns device, we must delegate the
unregistration to the work of the netns where the device actually
resides.
Let's add per-netns rtnl_work to support the deferred netdev
unregistration.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260703001009.1572444-4-kuniyu@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>