Date:   Tue, 7 Mar 2023 16:05:35 +0200
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     Michael Walle <michael@walle.cc>, sean.anderson@seco.com,
        davem@davemloft.net, edumazet@google.com, f.fainelli@gmail.com,
        hkallweit1@gmail.com, kuba@kernel.org,
        linux-kernel@vger.kernel.org, linux@armlinux.org.uk,
        netdev@vger.kernel.org, pabeni@redhat.com, tobias@waldekranz.com
Subject: Re: [PATCH net-next] net: mdio: Add netlink interface
Message-ID: <20230307140535.32ldprkyblpmicjg@skbuf>
References: <20230306204517.1953122-1-sean.anderson@seco.com>
 <20230307112307.777207-1-michael@walle.cc>
 <684c859a-02e2-4652-9a40-9607410f95e6@lunn.ch>
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On Tue, Mar 07, 2023 at 02:49:27PM +0100, Andrew Lunn wrote:
> On Tue, Mar 07, 2023 at 12:23:07PM +0100, Michael Walle wrote:
> > > To prevent userspace phy drivers, writes are disabled by default, and can
> > > only be enabled by editing the source.
> > 
> > Maybe we can just taint the kernel using add_taint()? I'm not sure if
> > that will prevent vendors writing user space drivers. Thoughts?
> 
> I was thinking about taint as well. But keep the same code structure,
> you need to edit it to enable write.

But as per the commit message, this locks us out of the following
legitimate uses:

- C45-over-C22 (reads)
- Atomic (why only atomic?) (read) access to paged registers

are we ok with the implications?