In comment173ca26e9b("samples/bpf: add comprehensive ipip, ipip6, ip6ip6 test") we added ip6ip6 test for bpf tunnel testing. But in commit933a741e3b("selftests/bpf: bpf tunnel test.") when we moved it to the current folder, we didn't add it. This patch add the ip6ip6 test back to bpf tunnel test. Update the ipip6's topology for both IPv4 and IPv6 testing. Since iperf test is removed as currect framework simplified it in purpose, I also removed unused tcp checkings in test_tunnel_kern.c. Fixes:933a741e3b("selftests/bpf: bpf tunnel test.") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201110015013.1570716-2-liuhangbin@gmail.com