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Date: Wed, 11 Mar 2026 23:59:43 +0100
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
To: Valentin Spreckels <valentin@spreckels.dev>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	wireguard@lists.zx2c4.com, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH wireguard] wireguard: prevent ipv6 addrconf via
 IFF_NO_ADDRCONF flag
Message-ID: <abHz3xcsLhIPc_Jn@zx2c4.com>
References: <20260208170545.31942-1-valentin@spreckels.dev>
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In-Reply-To: <20260208170545.31942-1-valentin@spreckels.dev>

Hi Valentin,

On Sun, Feb 08, 2026 at 06:05:45PM +0100, Valentin Spreckels wrote:
> Use the flag introduced in commit 8a321cf7becc6 ("net: add
> IFF_NO_ADDRCONF and use it in bonding to prevent ipv6 addrconf")
> instead of mangling the addr_gen_mode to prevent ipv6 addrconf.

Can you give some more context here? Why was IFF_NO_ADDRCONF added when
the IN6_ADDR_GEN_MODE_NONE method has been working fine? What's the
difference between these approaches? I don't doubt that your patch is
correct, but I would like to better understand this.

Jason