Re: [PATCH net-next] net: bcmgenet: Generate a random MAC if none is valid

[Scott Branden <scott.branden@broadcom.com>]

On 2019-10-11 4:19 p.m., Florian Fainelli wrote:
> Instead of having a hard failure and stopping the driver's probe
> routine, generate a random Ethernet MAC address to keep going.
>
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
> ---
>   drivers/net/ethernet/broadcom/genet/bcmgenet.c | 15 ++++++---------
>   1 file changed, 6 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
> index 12cb77ef1081..5c20829ffa0f 100644
> --- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
> +++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
> @@ -3461,16 +3461,10 @@ static int bcmgenet_probe(struct platform_device *pdev)
>   		goto err;
>   	}
>   
> -	if (dn) {
> +	if (dn)
>   		macaddr = of_get_mac_address(dn);
> -		if (IS_ERR(macaddr)) {
> -			dev_err(&pdev->dev, "can't find MAC address\n");
We shouldn't hide the error that the MAC address wasn't found.
We should continue to print some kind of error as generating a mac address
is a stop-gap measure and a proper MAC address should be used
for the board.
> -			err = -EINVAL;
> -			goto err;
> -		}
> -	} else {
> +	else
>   		macaddr = pd->mac_address;
> -	}
>   
>   	priv->base = devm_platform_ioremap_resource(pdev, 0);
>   	if (IS_ERR(priv->base)) {
> @@ -3482,7 +3476,10 @@ static int bcmgenet_probe(struct platform_device *pdev)
>   
>   	SET_NETDEV_DEV(dev, &pdev->dev);
>   	dev_set_drvdata(&pdev->dev, dev);
> -	ether_addr_copy(dev->dev_addr, macaddr);
> +	if (IS_ERR_OR_NULL(macaddr) || !is_valid_ether_addr(macaddr))
> +		eth_hw_addr_random(dev);
> +	else
> +		ether_addr_copy(dev->dev_addr, macaddr);
>   	dev->watchdog_timeo = 2 * HZ;
>   	dev->ethtool_ops = &bcmgenet_ethtool_ops;
>   	dev->netdev_ops = &bcmgenet_netdev_ops;