This is a note to let you know that I've just added the patch titled selftests: mptcp: join: fix subflow_send_ack lookup to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: selftests-mptcp-join-fix-subflow_send_ack-lookup.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c8f021eec5817601dbd25ab7e3ad5c720965c688 Mon Sep 17 00:00:00 2001 From: Geliang Tang <geliang.tang@xxxxxxxxx> Date: Fri, 15 Dec 2023 17:04:24 +0100 Subject: selftests: mptcp: join: fix subflow_send_ack lookup From: Geliang Tang <geliang.tang@xxxxxxxxx> commit c8f021eec5817601dbd25ab7e3ad5c720965c688 upstream. MPC backups tests will skip unexpected sometimes (For example, when compiling kernel with an older version of gcc, such as gcc-8), since static functions like mptcp_subflow_send_ack also be listed in /proc/kallsyms, with a 't' in front of it, not 'T' ('T' is for a global function): > grep "mptcp_subflow_send_ack" /proc/kallsyms 0000000000000000 T __pfx___mptcp_subflow_send_ack 0000000000000000 T __mptcp_subflow_send_ack 0000000000000000 t __pfx_mptcp_subflow_send_ack 0000000000000000 t mptcp_subflow_send_ack In this case, mptcp_lib_kallsyms_doesnt_have "mptcp_subflow_send_ack$" will be false, MPC backups tests will skip. This is not what we expected. The correct logic here should be: if mptcp_subflow_send_ack is not a global function in /proc/kallsyms, do these MPC backups tests. So a 'T' must be added in front of mptcp_subflow_send_ack. Fixes: 632978f0a961 ("selftests: mptcp: join: skip MPC backups tests if not supported") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Geliang Tang <geliang.tang@xxxxxxxxx> Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx> Signed-off-by: Matthieu Baerts <matttbe@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/net/mptcp/mptcp_join.sh | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/tools/testing/selftests/net/mptcp/mptcp_join.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh @@ -2773,7 +2773,7 @@ backup_tests() fi if reset "mpc backup" && - continue_if mptcp_lib_kallsyms_doesnt_have "mptcp_subflow_send_ack$"; then + continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow,backup speed=slow \ run_tests $ns1 $ns2 10.0.1.1 @@ -2782,7 +2782,7 @@ backup_tests() fi if reset "mpc backup both sides" && - continue_if mptcp_lib_kallsyms_doesnt_have "mptcp_subflow_send_ack$"; then + continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then pm_nl_add_endpoint $ns1 10.0.1.1 flags subflow,backup pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow,backup speed=slow \ @@ -2792,7 +2792,7 @@ backup_tests() fi if reset "mpc switch to backup" && - continue_if mptcp_lib_kallsyms_doesnt_have "mptcp_subflow_send_ack$"; then + continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow sflags=backup speed=slow \ run_tests $ns1 $ns2 10.0.1.1 @@ -2801,7 +2801,7 @@ backup_tests() fi if reset "mpc switch to backup both sides" && - continue_if mptcp_lib_kallsyms_doesnt_have "mptcp_subflow_send_ack$"; then + continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then pm_nl_add_endpoint $ns1 10.0.1.1 flags subflow pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow sflags=backup speed=slow \ Patches currently in stable-queue which might be from geliang.tang@xxxxxxxxx are queue-6.6/selftests-mptcp-join-fix-subflow_send_ack-lookup.patch