session = pool_elt_at_index (utm->sessions, p[0]);
hash_unset (utm->session_index_by_vpp_handles, key);
pool_put (utm->sessions, session);
session = pool_elt_at_index (utm->sessions, p[0]);
hash_unset (utm->session_index_by_vpp_handles, key);
pool_put (utm->sessions, session);