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Date:   Thu, 20 Oct 2022 18:36:36 +0300
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Ido Schimmel <idosch@nvidia.com>
Cc:     "Hans J. Schultz" <netdev@kapio-technology.com>,
        davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org,
        Florian Fainelli <f.fainelli@gmail.com>,
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        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Kurt Kanzenbach <kurt@linutronix.de>,
        Hauke Mehrtens <hauke@hauke-m.de>,
        Woojung Huh <woojung.huh@microchip.com>,
        UNGLinuxDriver@microchip.com, Sean Wang <sean.wang@mediatek.com>,
        Landen Chao <Landen.Chao@mediatek.com>,
        DENG Qingfang <dqfext@gmail.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Claudiu Manoil <claudiu.manoil@nxp.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
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Subject: Re: [PATCH v8 net-next 05/12] net: dsa: propagate the locked flag
 down through the DSA layer
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References: <20221018165619.134535-1-netdev@kapio-technology.com>
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On Thu, Oct 20, 2022 at 06:23:37PM +0300, Ido Schimmel wrote:
> 3. Miss. FDB entry not found. Here I was thinking to always tell the
> packet to go to the software data path so that it will trigger the
> creation of the "locked" entry if MAB is enabled. If MAB is not enabled,
> it will simply be dropped by the bridge. We can't control it per port in
> hardware, which is why the BR_PORT_MAB flag is not consulted.

Ah, ok, this is the part I was missing, so you can't control an FDB miss
to generate a learn frame only on some ports. But in principle, it still
is the BR_PORT_MAB flag the one which requires these frames to be generated,
not BR_PORT_LOCKED. You can have all ports LOCKED but not MAB, and no
learn frames will be necessary to be sent to the CPU. Only EAPOL, which
is link-local multicast, will reach software for further processing and
unlock the port for a certain MAC DA.