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Date:   Mon, 28 Jan 2019 16:57:49 +0100
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     Florian Fainelli <f.fainelli@gmail.com>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Gregory Clement <gregory.clement@bootlin.com>,
        Antoine Tenart <antoine.tenart@bootlin.com>,
        Maxime Chevallier <maxime.chevallier@bootlin.com>,
        Nadav Haklai <nadavh@marvell.com>
Subject: Re: [PATCH net-next v2 1/2] net: dsa: mv88e6xxx: Save switch rules
Message-ID: <20190128165749.6abf2dc4@xps13>
In-Reply-To: <20190128144417.GG4765@lunn.ch>
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        <c1421a5d-5f92-bb86-b5cc-9fa19a1c8d9f@gmail.com>
        <20190128152456.212ae5ac@xps13>
        <20190128144417.GG4765@lunn.ch>
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Hi Andrew,

Thanks for helping!

Andrew Lunn <andrew@lunn.ch> wrote on Mon, 28 Jan 2019 15:44:17 +0100:

> > I don't see where VLAN and bridge information are cached, can you point
> > me to the relevant locations?  
> 
> Miquèl
> 
> The bridge should have all that information. You need to ask it to
> enumerate the current configuration and replay it to the switch.
> 
> There might be something in the Mellanox driver you can copy? But i've
> not looked, i'm just guessing.

I am still searching but so far I did not find a mechanism reading the
configuration of the bridge out of a 'net' object. Indeed there are
multiple lists with the configuration but they are all 'mellanox'
objects, they do not belong to the core.

Maybe I don't find this configuration because I don't know what it is.
I imagine this configuration being one (or multiple) list(s), stored
somewhere in a net_device being a bridge. Am I on the wrong path?

Otherwise I might just save my own structures in net/dsa/switch.c like
I did for the mv88e6xx driver, and once this works, net-folks might
want to optimize the memory consumption and re-use the bridge
configuration directly?

> We also need to think about how we are going to test this. There is a
> lot of state information in a switch. So we are going to need some
> pretty good tests to show we have recreated all of it.

My understanding of all this is rather short, until know I used what
you proposed in the v1 of this series but I am all ears if I need to
add anything to my test list.


Thanks,
Miquèl