Subject: Re: [PATCH net v2 4/4] net: txgbe: fix to control VLAN strip

From: Simon Horman <[email-masked]>
Date: Thu, 9 May 2024 14:38:02 +0100

On Thu, May 09, 2024 at 11:08:46AM +0800, Jiawen Wu wrote:
> > > diff --git a/drivers/net/ethernet/wangxun/libwx/wx_lib.c b/drivers/net/ethernet/wangxun/libwx/wx_lib.c
> > > index aefd78455468..ed6a168ff136 100644
> > > --- a/drivers/net/ethernet/wangxun/libwx/wx_lib.c
> > > +++ b/drivers/net/ethernet/wangxun/libwx/wx_lib.c
> > > @@ -2692,9 +2692,9 @@ int wx_set_features(struct net_device *netdev, netdev_features_t features)
> > >
> > >  	netdev->features = features;
> > >
> > > -	if (changed &
> > > -	    (NETIF_F_HW_VLAN_CTAG_RX |
> > > -	     NETIF_F_HW_VLAN_STAG_RX))
> > > +	if (wx->mac.type == wx_mac_sp && changed & NETIF_F_HW_VLAN_CTAG_RX)
> > > +		wx->do_reset(netdev);
> > > +	else if (changed & (NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_CTAG_FILTER))
> > >  		wx_set_rx_mode(netdev);
> > >
> > >  	return 0;
> > 
> > Hi Jiawen Wu,
> > 
> > NETIF_F_HW_VLAN_CTAG_RX appears in both the "if" and "if else" condition.
> > Should "if else" be changed to "if" ?
> 
> There are 4 cases where wx_set_rx_mode() is called, CTAG_RX and CTAG_FILTER
> combined with wx_mac_sp and wx_mac_em. But only one special case that
> changing CTAG_RX requires wx_mac_sp device to do reset, and wx_set_rx_mode()
> also will be called during the reset process. So I think "if else" is more appropriate
> here.

Hi Jiawen Wu,

Thanks for your response.

Looking over this again it seems that I misread the code the first time
around. And i think that the current if ... else if ...  construction is
fine. Sorry for the noise.

Reviewed-by: Simon Horman <[email-masked]>