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Date:   Wed, 21 Sep 2022 05:42:58 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Nikolay Aleksandrov <razor@blackwall.org>
Cc:     Sevinj Aghayeva <sevinj.aghayeva@gmail.com>,
        netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        aroulin@nvidia.com, sbrivio@redhat.com, roopa@nvidia.com,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, linux-kernel@vger.kernel.org,
        bridge@lists.linux-foundation.org
Subject: Re: [PATCH RFC net-next 0/5] net: vlan: fix bridge binding behavior
 and add selftests
Message-ID: <20220921054258.41e06387@kernel.org>
In-Reply-To: <3f2d6682-7c5c-5a6d-110b-568331650949@blackwall.org>
References: <cover.1663445339.git.sevinj.aghayeva@gmail.com>
        <78bd0e54-4ee3-bd3c-2154-9eb8b9a70497@blackwall.org>
        <20220920162954.1f4aaf7b@kernel.org>
        <3f2d6682-7c5c-5a6d-110b-568331650949@blackwall.org>
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On Wed, 21 Sep 2022 07:45:07 +0300 Nikolay Aleksandrov wrote:
> > IDK, vlan knows it's calling the bridge:
> >=20
> > +	if ((vlan->flags ^ old_flags) & VLAN_FLAG_BRIDGE_BINDING &&
> > +	    netif_is_bridge_master(vlan->real_dev)) {
>=20
> This one is more of an optimization so notifications are sent only when t=
he bridge
> is involved, it can be removed if other interested parties show up.
>=20
> > bridge knows it's vlan calling:
> >=20
> > +	if (is_vlan_dev(dev)) {
> > +		br_vlan_device_event(dev, event, ptr);
> >=20
> > going thru the generic NETDEV notifier seems odd.
> >=20
> > If this is just to avoid the dependency we can perhaps add a stub=20
> > like net/ipv4/udp_tunnel_stub.c ?
>=20
> I suggested the notifier to be more generic and be able to re-use it for =
other link types although
> I don't have other use cases in mind right now. Stubs are an alternative =
as long as they and
> their lifetime are properly managed. I don't have a strong preference her=
e so if you prefer
> stubs I'm good.

Yup, stub seems simpler and more efficient to me. Only time will
tell if indeed this ntf type would have been reused further.. =F0=9F=A4=B7