Re: [PATCHv3] phy: fix crash in fixed_phy_add()

[David Miller <davem@davemloft.net>]

From: Rabin Vincent <rabin.vincent@axis.com>
Date: Wed, 18 May 2016 12:47:31 +0200

> From: Rabin Vincent <rabinv@axis.com>
> 
> Since e7f4dc3536a ("mdio: Move allocation of interrupts into core"),
> platforms which call fixed_phy_add() before fixed_mdio_bus_init() is
> called (for example, because the platform code and the fixed_phy driver
> use the same initcall level) crash in fixed_phy_add() since the
> ->mii_bus is not allocated.
> 
> Also since e7f4dc3536a, these interrupts are initalized to polling by
> default.  The few (old) platforms which directly use fixed_phy_add()
> from their platform code all pass PHY_POLL for the irq argument, so we
> can keep these platforms not crashing by simply not attempting to set
> the irq if PHY_POLL is passed.
> 
> Also, even if problems have not been reported on more modern platforms
> which used fixed_phy_register() from drivers' probe functions, we return
> -EPROBE_DEFER if the MDIO bus is not yet registered so that the probe is
> retried later.
> 
> Fixes: e7f4dc3536a400 ("mdio: Move allocation of interrupts into core")
> Signed-off-by: Rabin Vincent <rabinv@axis.com>
> ---
> v3: One more suggestion from Andrew: check mii bus state

Applied, thanks.