NSF_CLOSING
!(ns->netstack_flags & (NSF_UNINIT|NSF_CLOSING))) {
ASSERT(ns->netstack_flags & NSF_CLOSING);
if (ns->netstack_flags & (NSF_UNINIT | NSF_CLOSING)) {
if ((ns->netstack_flags & (NSF_UNINIT|NSF_CLOSING)) == 0) {
if (!(ns->netstack_flags & NSF_CLOSING) &&
ns->netstack_flags |= NSF_CLOSING;