[Intel-wired-lan] [PATCH iwl-net v1 2/2] ice: use NETIF_F_HW_CSUM instead of IP/IPV6

[Loktionov, Aleksandr]

> -----Original Message-----
> From: Michal Swiatkowski <michal.swiatkowski at linux.intel.com>
> Sent: Tuesday, April 28, 2026 9:07 AM
> To: intel-wired-lan at lists.osuosl.org
> Cc: netdev at vger.kernel.org; jramaseu at redhat.com; Nguyen, Anthony L
> <anthony.l.nguyen at intel.com>; Kitszel, Przemyslaw
> <przemyslaw.kitszel at intel.com>; Loktionov, Aleksandr
> <aleksandr.loktionov at intel.com>; Michal Swiatkowski
> <michal.swiatkowski at linux.intel.com>
> Subject: [PATCH iwl-net v1 2/2] ice: use NETIF_F_HW_CSUM instead of
> IP/IPV6
> 
> The hardware is capable of calculating checksum for IPV6 packets with
> extension header. To not drop such packets switch from IP/IPV6
> checksum to HW_CSUM.
I'd recommend "To not drop" -> "To avoid dropping"

> 
> HW_CSUM is also used in previous generation (i40e).
> 
> Previously HW_CSUM was used to indicate that hardware supports general
> checksum. Drop it assuming that if the hardware supports it, it is
> used.
> 
> Disabling offload for E830 in case of TSO isn't needed anymore as the
> check for TSO is done in Tx path just before preparation of the
> special GCS descriptor.
> 
> The commit from Fixes didn't introduce a bug, it just shown that the
> driver is doing sth wrong with the checksum features.
> 


Except commit message nits
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov at intel.com>

> Suggested-by: Jakub Ramaseuski <jramaseu at redhat.com>
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel at intel.com>
> Fixes: 04c20a9356f2 ("net: skip offload for NETIF_F_IPV6_CSUM if ipv6
> header contains extension")
> Signed-off-by: Michal Swiatkowski <michal.swiatkowski at linux.intel.com>
> ---
>  drivers/net/ethernet/intel/ice/ice_main.c | 21 +--------------------
>  1 file changed, 1 insertion(+), 20 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_main.c
> b/drivers/net/ethernet/intel/ice/ice_main.c
> index 15550216fbf0..0f2f949af536 100644
> --- a/drivers/net/ethernet/intel/ice/ice_main.c
> +++ b/drivers/net/ethernet/intel/ice/ice_main.c
> @@ -3500,9 +3500,8 @@ void ice_set_netdev_features(struct net_device
> *netdev)
>  			NETIF_F_RXHASH;
> 
>  	csumo_features = NETIF_F_RXCSUM	  |
> -			 NETIF_F_IP_CSUM  |
>  			 NETIF_F_SCTP_CRC |
> -			 NETIF_F_IPV6_CSUM;
> +			 NETIF_F_HW_CSUM;
> 
>  	vlano_features = NETIF_F_HW_VLAN_CTAG_FILTER |
>  			 NETIF_F_HW_VLAN_CTAG_TX     |
> @@ -3564,12 +3563,6 @@ void ice_set_netdev_features(struct net_device
> *netdev)
>  	/* Allow core to manage IRQs affinity */
>  	netif_set_affinity_auto(netdev);
> 
> -	/* Mutual exclusivity for TSO and GCS is enforced by the set
> features
> -	 * ndo callback.
> -	 */
> -	if (ice_is_feature_supported(pf, ICE_F_GCS))
> -		netdev->hw_features |= NETIF_F_HW_CSUM;
> -
>  	netif_set_tso_max_size(netdev, ICE_MAX_TSO_SIZE);  }
> 
> @@ -6489,18 +6482,6 @@ ice_set_features(struct net_device *netdev,
> netdev_features_t features)
>  	if (changed & NETIF_F_LOOPBACK)
>  		ret = ice_set_loopback(vsi, !!(features &
> NETIF_F_LOOPBACK));
> 
> -	/* Due to E830 hardware limitations, TSO (NETIF_F_ALL_TSO) with
> GCS
> -	 * (NETIF_F_HW_CSUM) is not supported.
> -	 */
> -	if (ice_is_feature_supported(pf, ICE_F_GCS) &&
> -	    ((features & NETIF_F_HW_CSUM) && (features &
> NETIF_F_ALL_TSO))) {
> -		if (netdev->features & NETIF_F_HW_CSUM)
> -			dev_err(ice_pf_to_dev(pf), "To enable TSO, you
> must first disable HW checksum.\n");
> -		else
> -			dev_err(ice_pf_to_dev(pf), "To enable HW
> checksum, you must first disable TSO.\n");
> -		return -EIO;
> -	}
> -
>  	return ret;
>  }
> 
> --
> 2.49.0