[ng_device newhook SLIST_REMOVE on non-member] Case 1: empty list, SLIST_REMOVE on never-inserted conn
  SLIST_FIRST(&sc_head_empty) = 0x0
  new_conn = 0x8004902c0
  invoking SLIST_REMOVE(&sc_head_empty, new_conn, ...)
Segmentation fault (core dumped)
RUN_EXIT=139