linux-kernel - Re: [RFC PATCH net-next 2/5] net: dsa: propagate flags down towards drivers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230118230135.szu6a7kvt2mjb3i5@skbuf>
Date:   Thu, 19 Jan 2023 01:01:35 +0200
From:   Vladimir Oltean <olteanv@...il.com>
To:     netdev@...io-technology.com
Cc:     davem@...emloft.net, kuba@...nel.org, netdev@...r.kernel.org,
        Florian Fainelli <f.fainelli@...il.com>,
        Andrew Lunn <andrew@...n.ch>,
        Eric Dumazet <edumazet@...gle.com>,
        Paolo Abeni <pabeni@...hat.com>,
        Kurt Kanzenbach <kurt@...utronix.de>,
        Hauke Mehrtens <hauke@...ke-m.de>,
        Woojung Huh <woojung.huh@...rochip.com>,
        "maintainer:MICROCHIP KSZ SERIES ETHERNET SWITCH DRIVER" 
        <UNGLinuxDriver@...rochip.com>, Sean Wang <sean.wang@...iatek.com>,
        Landen Chao <Landen.Chao@...iatek.com>,
        DENG Qingfang <dqfext@...il.com>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Claudiu Manoil <claudiu.manoil@....com>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>,
        Clément Léger <clement.leger@...tlin.com>,
        Jiri Pirko <jiri@...nulli.us>,
        Ivan Vecera <ivecera@...hat.com>,
        Roopa Prabhu <roopa@...dia.com>,
        Nikolay Aleksandrov <razor@...ckwall.org>,
        Russell King <linux@...linux.org.uk>,
        Christian Marangi <ansuelsmth@...il.com>,
        open list <linux-kernel@...r.kernel.org>,
        "moderated list:ARM/Mediatek SoC support" 
        <linux-arm-kernel@...ts.infradead.org>,
        "moderated list:ARM/Mediatek SoC support" 
        <linux-mediatek@...ts.infradead.org>,
        "open list:RENESAS RZ/N1 A5PSW SWITCH DRIVER" 
        <linux-renesas-soc@...r.kernel.org>,
        "moderated list:ETHERNET BRIDGE" <bridge@...ts.linux-foundation.org>
Subject: Re: [RFC PATCH net-next 2/5] net: dsa: propagate flags down towards
 drivers

On Wed, Jan 18, 2023 at 11:35:08PM +0100, netdev@...io-technology.com wrote:
> I am not sure I understand you entirely.
> From my standpoint I see it as so: that until now any fdb entry coming to
> port_fdb_add() (or port_fdb_del()) are seen as static entries. And this
> changes nothing with respect to those static entries as how drivers handle
> them.

This is true; it is implicit that the port_fdb_add() and port_fdb_del()
DSA methods request switches to operate on static FDB entries (in hardware).

> When the new dynamic flag is true, all drivers will ignore it in patch #3,
> so basically nothing will change by that.

This is not true, because it assumes that DSA never called port_fdb_add()
up until now for bridge FDB entries with the BR_FDB_STATIC flag unset,
which is incorrect (it did).

So what will change is that drivers which used to react to those bridge
FDB entries will stop doing so.

> Then in patch #5 the dynamic flag is handled by the mv88e6xxx driver.
> 
> I don't know the assisted_learning_on_cpu_port feature you mention, but
> there has still not been anything but static entries going towards
> port_fdb_add() yet...

For starters, you can read the commit message of the patch that
introduced it, which is d5f19486cee7 ("net: dsa: listen for
SWITCHDEV_{FDB,DEL}_ADD_TO_DEVICE on foreign bridge neighbors").