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Date:   Tue, 15 Jan 2019 23:40:12 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Heiner Kallweit <hkallweit1@gmail.com>
Cc:     Florian Fainelli <f.fainelli@gmail.com>,
        David Miller <davem@davemloft.net>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next] net: phy: check return code when requesting PHY
 driver module
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> I explicitly check for ret < 0. If there's no PHY driver module for
> a specific PHY ID then the return code would be > 0.
> My understanding of request_module() is that a return code < 0
> is returned if something bad happens in modprobe() call as such.

Ah, O.K. I was expecting an ENODEV or similar if there was no module
to load.

I wonder if this depends on the user space implementation? busybox
might do something different to udev?

Maybe add a comment about the expectation that no error is given when
the module does not exist.

    Andrew