Re: [PATCH net] net: fix feature changes on devices without ndo_set_features

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 11/13/2015 04:54 PM, Nikolay Aleksandrov wrote:

> From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
>
> When __netdev_update_features() was updated to ensure some features are
> disabled on new lower devices, an error was introduced for devices which
> don't have the ndo_set_features() method set. Before we'll just set the
> new features, but now we return an error and don't set them. Fix this by
> returning the old behaviour and setting err to 0 when ndo_set_features
> is not present.
>
> Fixes: e7868a85e1b2 ("net/core: ensure features get disabled on new lower devs")
> CC: Jarod Wilson <jarod@redhat.com>
> CC: Jiri Pirko <jiri@resnulli.us>
> CC: Ido Schimmel <idosch@mellanox.com>
> CC: Sander Eikelenboom <linux@eikelenboom.it>
> CC: Andy Gospodarek <gospo@cumulusnetworks.com>
> CC: Florian Fainelli <f.fainelli@gmail.com>
> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
> ---
> Sander please feel free to give your Tested-by.
>
>   net/core/dev.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/net/core/dev.c b/net/core/dev.c
> index ab9b8d0d115e..4a1d198dbbff 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -6426,6 +6426,8 @@ int __netdev_update_features(struct net_device *dev)
>
>   	if (dev->netdev_ops->ndo_set_features)
>   		err = dev->netdev_ops->ndo_set_features(dev, features);
> +	else
> +		err = 0;

    This makes the 'err' initializer pointless.

MBR, Sergei