phy: Fix phy_device_free memory leak

Fix memory leak in phy_device_free() for the case when phy_device*
returned by phy_device_create() is not registered in the system.

Bug description:
phy_device_create() sets name of kobject using dev_set_name(), which
allocates memory using kvasprintf(), but this memory isn't freed if
the underlying device isn't registered properly, because kobject_cleanup()
is not called in that case. This can happen (and actually is happening on
our machines) if phy_device_register(), called by mdiobus_scan(), fails.

Patch description:
Embedded struct device is initialized in phy_device_create() and it
counterpart phy_device_free() just drops one reference to the device,
which leads to proper deinitialization including releasing the kobject
name memory.

Signed-off-by: Petr Malat <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/phy/phy_device.c

···
 
 void phy_device_free(struct phy_device *phydev)
 {
-	kfree(phydev);
+	put_device(&phydev->dev);
 }
 EXPORT_SYMBOL(phy_device_free);
 
 static void phy_device_release(struct device *dev)
 {
-	phy_device_free(to_phy_device(dev));
+	kfree(to_phy_device(dev));
 }
 
 static struct phy_driver genphy_driver;
···
 	   driver will get bored and give up as soon as it finds that
 	   there's no driver _already_ loaded. */
 	request_module(MDIO_MODULE_PREFIX MDIO_ID_FMT, MDIO_ID_ARGS(phy_id));
+
+	device_initialize(&dev->dev);
 
 	return dev;
 }
···
 	/* Run all of the fixups for this PHY */
 	phy_scan_fixups(phydev);
 
-	err = device_register(&phydev->dev);
+	err = device_add(&phydev->dev);
 	if (err) {
-		pr_err("phy %d failed to register\n", phydev->addr);
+		pr_err("PHY %d failed to add\n", phydev->addr);
 		goto out;
 	}