Selftests are supposed to run on any kernels, including the old ones not supporting all MPTCP features. One of them is the support of the implicit endpoints introduced by commit d045b9eb95a9 ("mptcp: introduce implicit endpoints"). It is possible to look for "mptcp_subflow_send_ack" in kallsyms because it was needed to introduce the mentioned feature. So we can know in advance if the feature is supported instead of trying and accepting any results. Note that here and in the following commits, we re-do the same check for each sub-test of the same function for a few reasons. The main one is not to break the ID assign to each test in order to be able to easily compare results between different kernel versions. Also, we can still run a specific test even if it is skipped. Another reason is that it makes it clear during the review that a specific subtest will be skipped or not under certain conditions. At the end, it looks OK to call the exact same helper multiple times: it is not a critical path and it is the same code that is executed, not really more cases to maintain. Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368 Fixes: 69c6ce7b6eca ("selftests: mptcp: add implicit endpoint test case") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx> --- tools/testing/selftests/net/mptcp/mptcp_join.sh | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh index 3d4f22fe8f8c..7f860a93527f 100755 --- a/tools/testing/selftests/net/mptcp/mptcp_join.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh @@ -3272,8 +3272,10 @@ userspace_tests() endpoint_tests() { + # subflow_rebuild_header is needed to support the implicit flag # userspace pm type prevents add_addr - if reset "implicit EP"; then + if reset "implicit EP" && + mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then pm_nl_set_limits $ns1 2 2 pm_nl_set_limits $ns2 2 2 pm_nl_add_endpoint $ns1 10.0.2.1 flags signal @@ -3293,7 +3295,8 @@ endpoint_tests() kill_tests_wait fi - if reset "delete and re-add"; then + if reset "delete and re-add" && + mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then pm_nl_set_limits $ns1 1 1 pm_nl_set_limits $ns2 1 1 pm_nl_add_endpoint $ns2 10.0.2.2 id 2 dev ns2eth2 flags subflow -- 2.40.1