From: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx> commit 06b03083158e90d57866fa220de92c8dd8b9598b upstream. Selftests are supposed to run on any kernels, including the old ones not supporting all MPTCP features. One of them is the support of TCP_FASTOPEN socket option with MPTCP connections introduced by commit 4ffb0a02346c ("mptcp: add TCP_FASTOPEN sock option"). It is possible to look for "mptcp_fastopen_" in kallsyms to know if the feature is supported or not. Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368 Fixes: ca7ae8916043 ("selftests: mptcp: mptfo Initiator/Listener") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/net/mptcp/mptcp_connect.sh | 5 +++++ 1 file changed, 5 insertions(+) --- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh @@ -777,6 +777,11 @@ run_tests_peekmode() run_tests_mptfo() { + if ! mptcp_lib_kallsyms_has "mptcp_fastopen_"; then + echo "INFO: TFO not supported by the kernel: SKIP" + return + fi + echo "INFO: with MPTFO start" ip netns exec "$ns1" sysctl -q net.ipv4.tcp_fastopen=2 ip netns exec "$ns2" sysctl -q net.ipv4.tcp_fastopen=1