r0 = socket$inet6_udp(0xa, 0x2, 0x0)
ioctl$sock_inet6_SIOCDELRT(r0, 0x890b, &(0x7f0000000000)={@loopback, @mcast2, @empty, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1100000})