From: Lorenzo Bianconi <[email protected]>
Date: Tue, 17 Apr 2018 11:54:39 +0200
> Send a netlink notification when userspace adds a manually configured
> address if DAD is enabled and optimistic flag isn't set.
> Moreover send RTM_DELADDR notifications for tentative addresses.
>
> Some userspace applications (e.g. NetworkManager) are interested in
> addr netlink events albeit the address is still in tentative state,
> however events are not sent if DAD process is not completed.
> If the address is added and immediately removed userspace listeners
> are not notified. This behaviour can be easily reproduced by using
> veth interfaces:
>
> $ ip -b - <<EOF
>> link add dev vm1 type veth peer name vm2
>> link set dev vm1 up
>> link set dev vm2 up
>> addr add 2001:db8:a:b:1:2:3:4/64 dev vm1
>> addr del 2001:db8:a:b:1:2:3:4/64 dev vm1
> EOF
>
> This patch reverts the behaviour introduced by the commit f784ad3d79e5
> ("ipv6: do not send RTM_DELADDR for tentative addresses")
>
> Suggested-by: Thomas Haller <[email protected]>
> Signed-off-by: Lorenzo Bianconi <[email protected]>
Ok, applied to net-next.
It would be really nice if we clearly documented somewhere the exact
situations where we desire ipv6 address netlink notifications to be
sent out.
Maybe even a common function that guards the event emission, where we
encode the rules. Or a comment somewhere prominent. Something like
that.
Right now this isn't spelled out clearly anywhere, and that's probably
why things keep being adjusted back and forth like this.
Thank you.
