Yes, This kernel command line reliably reaches trigger_data_free() during boot:
trace_event=sched:sched_switch trace_trigger=sched_switch.traceon,sched_switch.traceon On an unpatched tree, that crashes during early boot before userspace. The call trace goes through: trigger_data_free() __kthread_create_on_node() try_to_wake_up() The stack also shows the boot-time trigger registration path: event_trigger_parse() trigger_process_regex() __trace_early_add_events() With v4 applied, the same command line boots successfully. The guest log shows: Failed to register trigger 'traceon' on event sched_switch And /sys/kernel/tracing/events/sched/sched_switch/trigger contains: traceon:unlimited I also verified patch 1 with repeated trace_trigger= parameters: before the patch, only the last parameter was preserved; after the patch, both triggers were installed. Thanks, Wesley Atwell
