From mboxrd@z Thu Jan  1 00:00:00 1970
From: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Subject: Re: [PATCH] ipv6: do not add link-local address if one already exists
Date: Mon, 11 Aug 2014 09:27:50 +0900
Message-ID: <53E80E06.3070704@miraclelinux.com>
References: <d630f87aa617098553c3a3361fcf50aa@mail.marples.name>
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Cc: hideaki.yoshifuji@miraclelinux.com,
	"David S. Miller\"" <davem@davemloft.net>,
	Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	Patrick McHardy <kaber@trash.net>
To: Roy Marples <roy@marples.name>, netdev@vger.kernel.org
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Hello.

Roy Marples wrote:
> Hi
>
> Currently the kernel will always add an IPv6 link-local address
> based on the hardware address when the interface is brought up.
> This is probably based on the assumption that userland would
> never add one before the interface is brought up.
>
> However, one at least one userland application (dhcpcd) does this so
> it can implement RFC7217 which can be used for link-local addresses
> as well.
>
> Attached is a patch which checks to see if a link-local address exists
> before indiscriminately adding one.

Well, I think this is incomplete, for example, we will continue generating
global address from eui64.

I think we should implement such functionality through "if token" bits.

--yoshfuji