ip_rt_min_pmtu 127 net/ipv4/route.c static u32 ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; ip_rt_min_pmtu 1025 net/ipv4/route.c if (mtu < ip_rt_min_pmtu) { ip_rt_min_pmtu 1027 net/ipv4/route.c mtu = min(old_mtu, ip_rt_min_pmtu); ip_rt_min_pmtu 3337 net/ipv4/route.c .data = &ip_rt_min_pmtu,