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Date:   Tue, 8 Aug 2023 16:27:07 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     Andrew Halaney <ahalaney@redhat.com>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        "David S . Miller" <davem@davemloft.net>,
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        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
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        Srini Kandagatla <srinivas.kandagatla@linaro.org>,
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        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Subject: Re: [PATCH 0/2] net: stmmac: allow sharing MDIO lines
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On Tue, Aug 08, 2023 at 05:15:45PM +0200, Andrew Lunn wrote:
> > > > > Good point, but it's worse than that: when MAC0 is unbound, it will
> > > > > unregister the MDIO bus and destroy all PHY devices. These are not
> > > > > refcounted so they will literally go from under MAC1. Not sure how
> > > > > this can be dealt with?
> > > >
> > > > unbinding is not a normal operation. So i would just live with it, and
> > > > if root decides to shoot herself in the foot, that is her choice.
> > > >
> > > 
> > > I disagree. Unbinding is very much a normal operation.
> 
> What do you use it for?
> 
> I don't think i've ever manually done it. Maybe as part of a script to
> unbind the FTDI driver from an FTDI device in order to use user space
> tools to program the EEPROM? But that is about it.
> 
> I actually expect many unbind operations are broken because it is very
> rarely used.

rmmod! Particularly useful during driver development, I tend to use it
extensively - and it has the advantage of testing those unbind paths!

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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