vxlan: honor per-nexthop fdb destination port

When an fdb entry points at a nexthop group, vxlan_fdb_nh_path_select()
resolves the selected leg's remote IP but leaves the UDP destination port
at the device default (vxlan->cfg.dst_port).

Extend nexthop_path_fdb_result() to also return the selected nexthop's
NHA_DST_PORT (0 when unset) and have vxlan_fdb_nh_path_select() store it
in rdst->remote_port.  vxlan_xmit_one() already prefers rdst->remote_port
when non-zero and falls back to the device port otherwise, so nexthops
without a port are unaffected.

This lets one fdb nexthop group load-balance a flow across legs that
share an underlay IP but differ in UDP destination port.

Signed-off-by: Jack Ma <jack4it@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260724-b4-vxlan-fdb-port-v5-2-cd1c6aeee058@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions