XFRM_STATE_NOPMTUDISC
x->props.flags |= XFRM_STATE_NOPMTUDISC;
if (x->props.flags & XFRM_STATE_NOPMTUDISC)
top_iph->frag_off = (flags & XFRM_STATE_NOPMTUDISC) || small_ipv6 ?
x->props.flags |= XFRM_STATE_NOPMTUDISC;
if (p->flags & XFRM_STATE_NOPMTUDISC) {