On 7/18/19 4:29 PM, Joe Lawrence wrote:
The livepatching self-tests tweak the dynamic debug config to verify the kernel log during the tests. Enhance set_dynamic_debug() so that the config changes are restored when the script exits. Note this functionality needs to keep in sync with: - dynamic_debug input/output formatting - functions affected by set_dynamic_debug() For example, push_dynamic_debug() transforms: kernel/livepatch/transition.c:530 [livepatch]klp_init_transition =_ "'%s': initializing %s transition\012" to: file kernel/livepatch/transition.c line 530 =_ Signed-off-by: Joe Lawrence <joe.lawrence@xxxxxxxxxx> --- .../testing/selftests/livepatch/functions.sh | 26 ++++++++++++++----- 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh index de5a504ffdbc..860f27665ebd 100644 --- a/tools/testing/selftests/livepatch/functions.sh +++ b/tools/testing/selftests/livepatch/functions.sh @@ -29,13 +29,27 @@ function die() { exit 1 }-# set_dynamic_debug() - setup kernel dynamic debug-# TODO - push and pop this config? +function push_dynamic_debug() { + DYNAMIC_DEBUG=$(grep '^kernel/livepatch' /sys/kernel/debug/dynamic_debug/control | \ + awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}') +} + +function pop_dynamic_debug() { + if [[ -n "$DYNAMIC_DEBUG" ]]; then + echo -n "$DYNAMIC_DEBUG" > /sys/kernel/debug/dynamic_debug/control + fi +} + +# set_dynamic_debug() - save the current dynamic debug config and tweak +# it for the self-tests. Set a script exit trap +# that restores the original config. function set_dynamic_debug() { - cat << EOF > /sys/kernel/debug/dynamic_debug/control -file kernel/livepatch/* +p -func klp_try_switch_task -p -EOF + push_dynamic_debug + trap pop_dynamic_debug EXIT INT TERM HUP + cat <<-EOF > /sys/kernel/debug/dynamic_debug/control + file kernel/livepatch/* +p + func klp_try_switch_task -p + EOF }# loop_until(cmd) - loop a command until it is successful or $MAX_RETRIES,
I took a stab as this while working on "[PATCH v2] selftests/livepatch: add test skip handling", which this applies on top of.
It works for me, though I feel that the /sys/kernel/debug/dynamic_debug/control output to input translation is brittle. It would be nice to have some kind of mass export/import capability for that interface.
-- Joe
