From: Ben Greear <redacted>
Date: Wed, 25 Aug 2010 11:26:17 -0700

By default, netlink messages are not sent when an IPv6 address
is added if it is in tentative state.  This makes it harder
for user-space applications to know the current state of the
IPv6 addresses.  This patch adds an ipv6 sysctl that will
allow tentative address notifications to be sent.  The sysctl
is off by default.

Signed-off-by: Ben Greear <redacted>

It's inconsistent to send two NEWADDR events for the same add.

I would advise that we unconditionally do the NEWADDR once,
when the tentative state address is added, and completely
elide the one we current send when it leaves tentative state.

Having a sysctl, and having it off by default, just means you haven't
actually fixes the problem.  Since it's only fixed if someone makes a
non-standard configuration change.

Otherwise what you're saying is that this is a very obscure thing for
very obscure applications, and it very nearly doesn't even matter
as a result.