Re: [PATCH v5 3/6] bpf: add BPF_F_ADJ_ROOM_DECAP_* flags for tunnel decapsulation

Willem de Bruijn
2026-04-20T19:44:14Z

Nick Hudson wrote:
> Add new bpf_skb_adjust_room() decapsulation flags:
>
> - BPF_F_ADJ_ROOM_DECAP_L4_GRE
> - BPF_F_ADJ_ROOM_DECAP_L4_UDP
> - BPF_F_ADJ_ROOM_DECAP_IPXIP4
> - BPF_F_ADJ_ROOM_DECAP_IPXIP6
>
> These flags let BPF programs describe which tunnel layer is being
> removed, so later changes can update tunnel-related GSO state
> accordingly during decapsulation.
>
> This patch only introduces the UAPI flag definitions and helper
> documentation.
>
> Co-developed-by: Max Tottenham <mtottenh@akamai.com>
> Signed-off-by: Max Tottenham <mtottenh@akamai.com>
> Co-developed-by: Anna Glasgall <aglasgal@akamai.com>
> Signed-off-by: Anna Glasgall <aglasgal@akamai.com>
> Signed-off-by: Nick Hudson <nhudson@akamai.com>

Reviewed-by: Willem de Bruijn <willemb@google.com>