Re: [PATCH] net: ethernet: ti: am65-cpsw-nuss: remove dead vid check in slave_add_vid()

[Siddharth Vadapalli <s-vadapalli@ti.com>]

On 16/05/26 4:27 AM, Alexander Vassilevski wrote:
> am65_cpsw_nuss_ndo_slave_add_vid() returns early at the top with:
> 
>      if (!netif_running(ndev) || !vid)
>          return 0;
> 
> so vid is guaranteed to be non-zero in the rest of the function. The
> subsequent
> 
>      if (!vid)
>          unreg_mcast = port_mask;
> 
> is therefore unreachable. unreg_mcast stays at its initialized value of
> zero and is passed as the unreg_mcast argument to
> cpsw_ale_vlan_add_modify().
> 
> Drop the dead branch. No functional change.
> 
> Found by Smatch.
> 
> Fixes: 7bcffde02152 ("net: ethernet: ti: am65-cpsw-nuss: restore vlan configuration while down/up")
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Closes: https://lore.kernel.org/kernel-janitors/aS_lhMwppbDHoEcX@stanley.mountain/
> Signed-off-by: Alexander Vassilevski <oss@vassilevski.com>


Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>


> ---
>   drivers/net/ethernet/ti/am65-cpsw-nuss.c | 2 --
>   1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> index 7ac75fc8cd..77f59996a0 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> @@ -316,8 +316,6 @@ static int am65_cpsw_nuss_ndo_slave_add_vid(struct net_device *ndev,
>   		return ret;
>   
>   	port_mask = BIT(port->port_id) | ALE_PORT_HOST;
> -	if (!vid)
> -		unreg_mcast = port_mask;
>   	dev_info(common->dev, "Adding vlan %d to vlan filter\n", vid);
>   	ret = cpsw_ale_vlan_add_modify(common->ale, vid, port_mask,
>   				       unreg_mcast, port_mask, 0);