Like commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue() using a macro") says, flush_scheduled_work() is dangerous and will be forbidden. We are on the way for removing all flush_scheduled_work() callers from the kernel, and there are only 4 callers remaining as of linux-20221104. drivers/gpu/drm/i915/display/intel_display.c:8997: flush_scheduled_work(); drivers/gpu/drm/i915/gt/selftest_execlists.c:88: flush_scheduled_work(); drivers/md/dm.c:234: flush_scheduled_work(); drivers/message/fusion/mptscsih.c:1234: flush_scheduled_work(); I'm planning to start emitting runtime messages in linux-next.git tree.