The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 63c643aa7b7287fdbb0167063785f89ece3f000f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025112058-distinct-glisten-21aa@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 63c643aa7b7287fdbb0167063785f89ece3f000f Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" matttbe@kernel.org Date: Mon, 10 Nov 2025 19:23:40 +0100 Subject: [PATCH] selftests: mptcp: connect: fix fallback note due to OoO

The "fallback due to TCP OoO" was never printed because the stat_ooo_now variable was checked twice: once in the parent if-statement, and one in the child one. The second condition was then always true then, and the 'else' branch was never taken.

The idea is that when there are more ACK + MP_CAPABLE than expected, the test either fails if there was no out of order packets, or a notice is printed.

Fixes: 69ca3d29a755 ("mptcp: update selftest for fallback due to OoO") Cc: stable@vger.kernel.org Reviewed-by: Geliang Tang geliang@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Link: https://patch.msgid.link/20251110-net-mptcp-sft-join-unstable-v1-1-a4332c714... Signed-off-by: Jakub Kicinski kuba@kernel.org

diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh index 47ecb5b3836e..9b7b93f8eb0c 100755 --- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh @@ -492,7 +492,7 @@ do_transfer() "than expected (${expect_synrx})" retc=1 fi - if [ ${stat_ackrx_now_l} -lt ${expect_ackrx} ] && [ ${stat_ooo_now} -eq 0 ]; then + if [ ${stat_ackrx_now_l} -lt ${expect_ackrx} ]; then if [ ${stat_ooo_now} -eq 0 ]; then mptcp_lib_pr_fail "lower MPC ACK rx (${stat_ackrx_now_l})" \ "than expected (${expect_ackrx})"