On 7/4/25 10:53 AM, chia-yu.chang@xxxxxxxxxxxxxxxxxxx wrote: > @@ -443,9 +456,34 @@ static inline void tcp_accecn_set_ace(struct tcp_sock *tp, struct sk_buff *skb, > } > } > > +static inline u8 tcp_accecn_option_init(const struct sk_buff *skb, > + u8 opt_offset) > +{ > + u8 *ptr = skb_transport_header(skb) + opt_offset; > + unsigned int optlen = ptr[1] - 2; > + > + WARN_ON_ONCE(ptr[0] != TCPOPT_ACCECN0 && ptr[0] != TCPOPT_ACCECN1); You should probably error out from this function when WARN_ON_ONCE() is true. I've no idea about the possibly meaningful error value to be returned. /P