Re: [PATCH net] ipv6/addrconf: allow adding multicast addr if IFA_F_MCAUTOJOIN is set

From: Hangbin Liu <redacted>
Date: Tue, 13 Aug 2019 21:52:32 +0800

The ip address autojoin is not working for IPv6 as ipv6_add_addr()
will return -EADDRNOTAVAIL when adding a multicast address.

Reported-by: Jianlin Shi <redacted>
Fixes: 93a714d6b53d ("multicast: Extend ip address command to enable multicast group join/leave on")
Signed-off-by: Hangbin Liu <redacted>

I don't understand how all of this works and why ipv6_add_addr(), which
seems designed explicitly to exclude multicast addresses, should accept
them and what all of the possible fallout might be from such a change.

Your commit message is way too terse and makes it impossible to evaluate
your change.  Really, a change of this nature should have a couple paragraphs
of text explaining the existing situation, what is wrong with it, how you
are fixing it, and why you are fixing it that way.

Thanks.