Hi,
On Tue, Jan 26, 2016 at 03:12:30PM +0100, Andrew Lunn wrote:
> of_phy_find_device() is used to find the phy device associated with a
> device node. It is expected the node is for a PHY device, but in fact
> it could of been probed as a generic MDIO device. Ensure the device is
> a PHY before returning it.
>
> Fixes: a9049e0c513c ("mdio: Add support for mdio drivers.")
> Reported-by: Aaro Koskinen <aaro.koski...@nokia.com>
> Reported-by: Olof Johansson <o...@lixom.net>
> Signed-off-by: Andrew Lunn <and...@lunn.ch>
This fixes the crash for me, so:
Tested-by: Aaro Koskinen <aaro.koski...@nokia.com>
> ---
>
> This is only 1/2 the fix. It will stop the NULL pointer dereference in
> the mutex code, but the Ethernet device probe is likely to return an
> error when it cannot find its PHY.
Yes, it's still not possible to actually use mgmt0:
$ ifconfig mgmt0 up
[ 74.432849] octeon_mgmt 1070000100000.ethernet: Cannot initialize PHY on MIX0
A.
> ---
> drivers/of/of_mdio.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
> index 86829f8064a6..b5aa004a24b6 100644
> --- a/drivers/of/of_mdio.c
> +++ b/drivers/of/of_mdio.c
> @@ -256,11 +256,19 @@ static int of_phy_match(struct device *dev, void
> *phy_np)
> struct phy_device *of_phy_find_device(struct device_node *phy_np)
> {
> struct device *d;
> + struct mdio_device *mdiodev;
> +
> if (!phy_np)
> return NULL;
>
> d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
> - return d ? to_phy_device(d) : NULL;
> + if (d) {
> + mdiodev = to_mdio_device(d);
> + if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
> + return to_phy_device(d);
> + }
> +
> + return NULL;
> }
> EXPORT_SYMBOL(of_phy_find_device);
>
> --
> 2.7.0
>
