Hi Andreas, Pablo, Jonas,
I think that the SGSN/GGSN role flag (or whatever it may end up being called) logically belongs in the gtp-device at this point, and will in the future belong to the UDP/GTP-socket (with Andreas' proposed changes). Having it per-pdp-context indeed seems odd and just provide a way to create broken configurations (and increase the memory use per pdp context, of which you have many more than netdevs or gtp-sockets).