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Message-ID: <3f2d6682-7c5c-5a6d-110b-568331650949@blackwall.org>
Date:   Wed, 21 Sep 2022 07:45:07 +0300
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Subject: Re: [PATCH RFC net-next 0/5] net: vlan: fix bridge binding behavior
 and add selftests
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To:     Jakub Kicinski <kuba@kernel.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
References: <cover.1663445339.git.sevinj.aghayeva@gmail.com>
 <78bd0e54-4ee3-bd3c-2154-9eb8b9a70497@blackwall.org>
 <20220920162954.1f4aaf7b@kernel.org>
From:   Nikolay Aleksandrov <razor@blackwall.org>
In-Reply-To: <20220920162954.1f4aaf7b@kernel.org>
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On 21/09/2022 02:29, Jakub Kicinski wrote:
> On Tue, 20 Sep 2022 12:16:26 +0300 Nikolay Aleksandrov wrote:
>> The set looks good to me, the bridge and vlan direct dependency is gone and
>> the new notification type is used for passing link type specific info.
> 
> IDK, vlan knows it's calling the bridge:
> 
> +	if ((vlan->flags ^ old_flags) & VLAN_FLAG_BRIDGE_BINDING &&
> +	    netif_is_bridge_master(vlan->real_dev)) {
> 

This one is more of an optimization so notifications are sent only when the bridge
is involved, it can be removed if other interested parties show up.

> bridge knows it's vlan calling:
> 
> +	if (is_vlan_dev(dev)) {
> +		br_vlan_device_event(dev, event, ptr);
> 
> going thru the generic NETDEV notifier seems odd.
> 
> If this is just to avoid the dependency we can perhaps add a stub 
> like net/ipv4/udp_tunnel_stub.c ?
> 

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 here so if you prefer
stubs I'm good.

>> If the others are ok with it I think you can send it as non-RFC, but I'd give it
>> a few more days at least. :)

Cheers,
 Nik