With procfs v3.3.16, the sysctl command doesn't print the set key and value on error. This change breaks livepatch selftest test-ftrace.sh, that tests the interaction of sysctl ftrace_enabled: Make it work with all sysctl versions using '-q' option. Explicitly print the final status on success so that it can be verified in the log. The error message is enough on failure. Reported-by: Kamalesh Babulal <kamalesh@xxxxxxxxxxxxxxxxxx> Signed-off-by: Petr Mladek <pmladek@xxxxxxxx> --- The patch has been created against livepatch.git, branch for-5.9/selftests-cleanup. But it applies also against the current Linus' tree. tools/testing/selftests/livepatch/functions.sh | 3 ++- tools/testing/selftests/livepatch/test-ftrace.sh | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh index 408529d94ddb..1aba83c87ad3 100644 --- a/tools/testing/selftests/livepatch/functions.sh +++ b/tools/testing/selftests/livepatch/functions.sh @@ -75,7 +75,8 @@ function set_dynamic_debug() { } function set_ftrace_enabled() { - result=$(sysctl kernel.ftrace_enabled="$1" 2>&1 | paste --serial --delimiters=' ') + result=$(sysctl -q kernel.ftrace_enabled="$1" 2>&1 && \ + sysctl kernel.ftrace_enabled 2>&1) echo "livepatch: $result" > /dev/kmsg } diff --git a/tools/testing/selftests/livepatch/test-ftrace.sh b/tools/testing/selftests/livepatch/test-ftrace.sh index 9160c9ec3b6f..552e165512f4 100755 --- a/tools/testing/selftests/livepatch/test-ftrace.sh +++ b/tools/testing/selftests/livepatch/test-ftrace.sh @@ -51,7 +51,7 @@ livepatch: '$MOD_LIVEPATCH': initializing patching transition livepatch: '$MOD_LIVEPATCH': starting patching transition livepatch: '$MOD_LIVEPATCH': completing patching transition livepatch: '$MOD_LIVEPATCH': patching complete -livepatch: sysctl: setting key \"kernel.ftrace_enabled\": Device or resource busy kernel.ftrace_enabled = 0 +livepatch: sysctl: setting key \"kernel.ftrace_enabled\": Device or resource busy % echo 0 > /sys/kernel/livepatch/$MOD_LIVEPATCH/enabled livepatch: '$MOD_LIVEPATCH': initializing unpatching transition livepatch: '$MOD_LIVEPATCH': starting unpatching transition -- 2.26.2