On 10/1/24 13:44, Simon Horman wrote: [...] >>> From: Paul Barker <paul.barker.ct@xxxxxxxxxxxxxx> >>> >>> The GbEth IP supports offloading checksum calculation for VLAN-tagged >>> packets, provided that the EtherType is 0x8100 and only one VLAN tag is >>> present. >>> >>> Signed-off-by: Paul Barker <paul.barker.ct@xxxxxxxxxxxxxx> >> [...] >> >>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c >>> index 832132d44fb4..eb7499d42a9b 100644 >>> --- a/drivers/net/ethernet/renesas/ravb_main.c >>> +++ b/drivers/net/ethernet/renesas/ravb_main.c >>> @@ -2063,11 +2063,30 @@ static void ravb_tx_timeout_work(struct work_struct *work) >>> >>> static bool ravb_can_tx_csum_gbeth(struct sk_buff *skb) >>> { >>> - /* TODO: Need to add support for VLAN tag 802.1Q */ >>> - if (skb_vlan_tag_present(skb)) >>> + u16 net_protocol = ntohs(skb->protocol); >>> + >>> + /* GbEth IP can calculate the checksum if: >>> + * - there are zero or one VLAN headers with TPID=0x8100 >>> + * - the network protocol is IPv4 or IPv6 >>> + * - the transport protocol is TCP, UDP or ICMP >>> + * - the packet is not fragmented >>> + */ >>> + >>> + if (skb_vlan_tag_present(skb) && >>> + (skb->vlan_proto != ETH_P_8021Q || net_protocol == ETH_P_8021Q)) >> >> Not sure I understand this check... Maybe s/==/!=/? > > A minor nit if the check stays in some form: > vlan_proto is big endian, while ETH_P_8021Q is host byte order. Not minor at all, thanks for spotting! Luckily, we also have a kernel test robot which runs sparse. :-) [...] MBR, Sergey