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Date:   Fri, 27 Mar 2020 00:34:11 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Heiner Kallweit <hkallweit1@gmail.com>
Cc:     Florian Fainelli <f.fainelli@gmail.com>,
        Russell King - ARM Linux <linux@armlinux.org.uk>,
        David Miller <davem@davemloft.net>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next] net: phy: probe PHY drivers synchronously
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On Thu, Mar 26, 2020 at 07:16:23PM +0100, Heiner Kallweit wrote:
> If we have scenarios like
> 
> mdiobus_register()
> 	-> loads PHY driver module(s)
> 	-> registers PHY driver(s)
> 	-> may schedule async probe
> phydev = mdiobus_get_phy()
> <phydev action involving PHY driver>
> 
> or
> 
> phydev = phy_device_create()
> 	-> loads PHY driver module
> 	-> registers PHY driver
> 	-> may schedule async probe
> <phydev action involving PHY driver>
> 
> then we expect the PHY driver to be bound to the phydev when triggering
> the action. This may not be the case in case of asynchronous probing.
> Therefore ensure that PHY drivers are probed synchronously.

Hi Heiner

We have been doing asynchronous driver loads since forever, and not
noticed any problem. Do you have a real example of it going wrong?

	Andrew