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Date:   Thu, 14 Dec 2023 14:00:16 +0200
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Serge Semin <fancer.lancer@gmail.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        Jose Abreu <Jose.Abreu@synopsys.com>,
        Maxime Chevallier <maxime.chevallier@bootlin.com>,
        Tomer Maimon <tmaimon77@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, openbmc@lists.ozlabs.org,
        netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next 10/16] net: pcs: xpcs: Add generic DW XPCS
 MDIO-device support
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On Thu, Dec 14, 2023 at 02:54:00PM +0300, Serge Semin wrote:
> > > > The pcs-rzn1-miic.c driver puts a device_link to the MAC to at least
> > > > tear down the whole thing when the PCS is unbound, which is saner than
> > > > crashing the kernel. I don't see the equivalent protection mechanism here?
> > > 
> > > You are right. I don't have any equivalent protection here. Thanks for
> > > suggesting a solution.
> > 
> > I think that a device link between the "ethernet" device and the "mdio"
> > device (controller, parent of the PHY or PCS), if the Ethernet is not a
> > parent of the MDIO controller, could also solve that. But it would also
> > require ACK from PHY maintainers, who may have grander plans to address
> > this snag.
> 
> Ok. I'll add it in v2. Let's see what the maintainers think about
> that.

Are you not following the parallel discussion on the topic of PCS
devices having bound drivers?
https://lore.kernel.org/netdev/ZXnV%2FPk1PYxAm%2FjS@shell.armlinux.org.uk/

Sadly I don't have much spare time to join that discussion, but it looks
like you could.