Re: [PATCH bpf-next 0/2] Clarify and Enhance XDP Rx Metadata Handling

On Tue, 1 Jul 2025 12:29:38 +0800 Song Yoong Siang wrote:

                    |<---sizeof(xdp_meta)--|
                    |                      |
             struct xdp_meta               rx_desc->address
                    ^                      ^
                    |                      |

+----------+----------------------+------------+------+ | headroom | custom metadata | reserved | data | +----------+----------------------+------------+------+ ^ ^ ^ | | | struct xdp_meta xdp_buff->data_meta xdp_buff->data | | |<---sizeof(xdp_meta)--|

Huh. Did AF_XDP maintainers explicitly sign off on this or it's just how IGC implementation works and nobody noticed?

For normal XDP my understanding is that its the driver's responsibility to move the "reserved" stuff out of place before presenting the frame to program.