Re: [PATCH net v2 1/3] net: phy: Fix PHY module checks

[Andrew Lunn]

> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -920,7 +920,7 @@ int phy_attach_direct(struct net_device *dev, struct 
> phy_device *phydev,
>               return -EIO;
>       }
>  
> -     if (!try_module_get(d->driver->owner)) {
> +     if (d->driver && !try_module_get(d->driver->owner)) {
>               dev_err(&dev->dev, "failed to get the device driver module\n");
>               return -EIO;
>       }
> @@ -943,7 +943,7 @@ int phy_attach_direct(struct net_device *dev, struct 
> phy_device *phydev,
>                       err = device_bind_driver(d);
>  
>               if (err)
> -                     goto error;
> +                     goto error_put_device;
>       }
>  
>       if (phydev->attached_dev) {
> @@ -981,6 +981,7 @@ int phy_attach_direct(struct net_device *dev, struct 
> phy_device *phydev,
>  
>  error:
>       phy_detach(phydev);
> +error_put_device:
>       put_device(d);
>       module_put(d->driver->owner);

Can we get into problems here? Maybe we did not do a get?


>       if (ndev_owner != bus->owner)
> @@ -1065,7 +1066,8 @@ void phy_detach(struct phy_device *phydev)
>       bus = phydev->mdio.bus;
>  
>       put_device(&phydev->mdio.dev);
> -     module_put(phydev->mdio.dev.driver->owner);
> +     if (phydev->mdio.dev.driver)
> +             module_put(phydev->mdio.dev.driver->owner);

Humm. By this point, havn't we assigned d->driver to genphy_driver?
So this decrements something we never incremented?

To me, it seems better to move the try_module_get() after assigning
genphy_driver if needed. We then don't have any special conditions.

      Andrew