A customer using nohz_full has experienced the following interruption: oslat-1004510 [018] timer_cancel: timer=0xffff90a7ca663cf8 oslat-1004510 [018] timer_expire_entry: timer=0xffff90a7ca663cf8 function=delayed_work_timer_fn now=4709188240 baseclk=4709188240 oslat-1004510 [018] workqueue_queue_work: work struct=0xffff90a7ca663cd8 function=fb_flashcursor workqueue=events_power_efficient req_cpu=8192 cpu=18 oslat-1004510 [018] workqueue_activate_work: work struct 0xffff90a7ca663cd8 oslat-1004510 [018] sched_wakeup: kworker/18:1:326 [120] CPU:018 oslat-1004510 [018] timer_expire_exit: timer=0xffff90a7ca663cf8 oslat-1004510 [018] irq_work_entry: vector=246 oslat-1004510 [018] irq_work_exit: vector=246 oslat-1004510 [018] tick_stop: success=0 dependency=SCHED oslat-1004510 [018] hrtimer_start: hrtimer=0xffff90a70009cb00 function=tick_sched_timer/0x0 ... oslat-1004510 [018] softirq_exit: vec=1 [action=TIMER] oslat-1004510 [018] softirq_entry: vec=7 [action=SCHED] oslat-1004510 [018] softirq_exit: vec=7 [action=SCHED] oslat-1004510 [018] tick_stop: success=0 dependency=SCHED oslat-1004510 [018] sched_switch: oslat:1004510 [120] R ==> kworker/18:1:326 [120] kworker/18:1-326 [018] workqueue_execute_start: work struct 0xffff90a7ca663cd8: function fb_flashcursor kworker/18:1-326 [018] workqueue_queue_work: work struct=0xffff9078f119eed0 function=drm_fb_helper_damage_work workqueue=events req_cpu=8192 cpu=18 kworker/18:1-326 [018] workqueue_activate_work: work struct 0xffff9078f119eed0 kworker/18:1-326 [018] timer_start: timer=0xffff90a7ca663cf8 function=delayed_work_timer_fn ... Set wq_power_efficient to true, in case nohz_full is enabled. This makes the power efficient workqueue be unbounded, which allows workqueue items there to be moved to HK CPUs. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>