BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 141s! Showing busy workqueues and worker pools: workqueue events: flags=0x100 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: legacy_dvb_usb_read_remote_control, vmstat_shepherd, free_obj_work pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3 in-flight: 23:legacy_dvb_usb_read_remote_control pending: legacy_dvb_usb_read_remote_control workqueue events_unbound: flags=0x2 pwq 8: cpus=0-1 flags=0x4 nice=0 active=4 refcnt=5 in-flight: 36:fsnotify_connector_destroy_workfn fsnotify_connector_destroy_workfn ,1589:fsnotify_mark_destroy_workfn fsnotify_mark_destroy_workfn workqueue events_power_efficient: flags=0x180 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=9 refcnt=10 pending: 2*neigh_managed_work, 2*neigh_periodic_work, do_cache_clean, gc_worker, 3*check_lifetime workqueue rcu_gp: flags=0x108 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: srcu_invoke_callbacks workqueue mm_percpu_wq: flags=0x8 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: vmstat_update workqueue usb_hub_wq: flags=0x104 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=8 refcnt=9 in-flight: 10:hub_event hub_event ,2593:hub_event hub_event ,5529:hub_event hub_event ,5526:hub_event hub_event pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=2 refcnt=3 in-flight: 1117:hub_event hub_event pool 2: cpus=0 node=0 flags=0x0 nice=0 hung=142s workers=7 idle: 9 5295 5234 pool 6: cpus=1 node=0 flags=0x0 nice=0 hung=0s workers=8 idle: 5219 38 7084 5240 pool 8: cpus=0-1 flags=0x4 nice=0 hung=0s workers=6 idle: 1628 262 12 8748 Showing backtraces of running workers in stalled CPU-bound worker pools: pool 2: task:kworker/0:1 state:R running task stack:21512 pid:10 tgid:10 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145d/0x4a00 kernel/sched/core.c:6863 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047 __cond_resched+0x22/0x30 kernel/sched/core.c:7376 might_resched include/linux/kernel.h:61 [inline] down_write+0x73/0x200 kernel/locking/rwsem.c:1589 kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:796 __kernfs_create_file+0x295/0x350 fs/kernfs/file.c:1086 sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:313 sysfs_merge_group+0x1aa/0x340 fs/sysfs/group.c:382 dpm_sysfs_add+0x237/0x280 drivers/base/power/sysfs.c:704 device_add+0x9cc/0x1980 drivers/base/core.c:3649 usb_create_ep_devs+0x160/0x2b0 drivers/usb/core/endpoint.c:170 create_intf_ep_devs.isra.0+0x161/0x200 drivers/usb/core/message.c:1252 usb_set_configuration+0x11a7/0x1e50 drivers/usb/core/message.c:2216 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 pool 2: task:kworker/0:2 state:R running task stack:21768 pid:2593 tgid:2593 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145d/0x4a00 kernel/sched/core.c:6863 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047 __cond_resched+0x22/0x30 kernel/sched/core.c:7376 might_resched include/linux/kernel.h:61 [inline] might_alloc include/linux/sched/mm.h:323 [inline] might_alloc include/linux/sched/mm.h:315 [inline] slab_pre_alloc_hook mm/slub.c:4904 [inline] slab_alloc_node mm/slub.c:5239 [inline] __kmalloc_cache_noprof+0x3fc/0x7e0 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] usb_cache_string+0x5d/0x150 drivers/usb/core/message.c:1028 usb_enumerate_device drivers/usb/core/hub.c:2537 [inline] usb_new_device+0x169/0x1a90 drivers/usb/core/hub.c:2665 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 pool 2: task:kworker/0:8 state:R running task stack:21192 pid:5529 tgid:5529 ppid:2 task_flags:0x4208060 flags:0x00080010 Workqueue: usb_hub_wq hub_event Call Trace: sched_show_task kernel/sched/core.c:7819 [inline] sched_show_task+0x423/0x630 kernel/sched/core.c:7794 show_cpu_pool_hog kernel/workqueue.c:7535 [inline] show_cpu_pools_hogs kernel/workqueue.c:7555 [inline] wq_watchdog_timer_fn+0x830/0xae0 kernel/workqueue.c:7638 call_timer_fn+0x19a/0x5a0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers+0x74a/0xae0 kernel/time/timer.c:2373 __run_timer_base kernel/time/timer.c:2385 [inline] __run_timer_base kernel/time/timer.c:2377 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2394 run_timer_softirq+0x24/0x40 kernel/time/timer.c:2405 handle_softirqs+0x208/0x940 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__orc_find+0x60/0xf0 arch/x86/kernel/unwind_orc.c:101 Code: 89 ff 48 89 fd eb 0c 48 8d 6b 04 49 89 df 49 39 ec 72 4e 4c 89 e2 48 29 ea 48 89 d6 48 c1 ea 3f 48 c1 fe 02 48 01 f2 48 d1 fa <48> 8d 5c 95 00 48 89 da 48 c1 ea 03 0f b6 34 0a 48 89 da 83 e2 07 RSP: 0018:ffffc9000392e888 EFLAGS: 00000202 RAX: ffffffff8b31d048 RBX: ffffffff8acec480 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffffffff8acec474 RBP: ffffffff8acec474 R08: ffffffff8b31d078 R09: 000000003deb29de R10: 0000000000000002 R11: 000000000002863d R12: ffffffff8acec47c R13: ffffffff83863d3d R14: ffffffff8acec474 R15: ffffffff8acec474 orc_find arch/x86/kernel/unwind_orc.c:238 [inline] unwind_next_frame+0x2ec/0x20b0 arch/x86/kernel/unwind_orc.c:510 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_node_noprof+0x2a8/0x7e0 mm/slub.c:5315 __alloc_skb+0x156/0x410 net/core/skbuff.c:679 __netdev_alloc_skb+0x7a/0x920 net/core/skbuff.c:754 netdev_alloc_skb include/linux/skbuff.h:3484 [inline] dev_alloc_skb include/linux/skbuff.h:3497 [inline] ath6kl_usb_post_recv_transfers.constprop.0+0x55/0x400 drivers/net/wireless/ath/ath6kl/usb.c:428 ath6kl_usb_start_recv_pipes drivers/net/wireless/ath/ath6kl/usb.c:498 [inline] hif_start drivers/net/wireless/ath/ath6kl/usb.c:703 [inline] ath6kl_usb_power_on+0x8e/0x160 drivers/net/wireless/ath/ath6kl/usb.c:1062 ath6kl_hif_power_on drivers/net/wireless/ath/ath6kl/hif-ops.h:136 [inline] ath6kl_core_init+0x17e/0x11b0 drivers/net/wireless/ath/ath6kl/core.c:97 ath6kl_usb_probe+0xcee/0x1440 drivers/net/wireless/ath/ath6kl/usb.c:1168 usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_set_configuration+0x1187/0x1e50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 pool 2: task:kworker/0:7 state:R running task stack:23240 pid:5526 tgid:5526 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145d/0x4a00 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121 usb_start_wait_urb+0x145/0x4e0 drivers/usb/core/message.c:64 usb_internal_control_msg drivers/usb/core/message.c:103 [inline] usb_control_msg+0x326/0x4a0 drivers/usb/core/message.c:154 snd_usb_ctl_msg+0xce/0x190 sound/usb/helper.c:93 init_pitch_v2 sound/usb/pcm.c:227 [inline] snd_usb_init_pitch+0x256/0x420 sound/usb/pcm.c:253 __snd_usb_parse_audio_interface+0x25ab/0x4760 sound/usb/stream.c:1265 snd_usb_parse_audio_interface+0x7c/0x110 sound/usb/stream.c:1279 snd_usb_create_stream.isra.0+0x245/0x580 sound/usb/card.c:319 snd_usb_create_streams sound/usb/card.c:392 [inline] usb_audio_probe+0x1094/0x3ea0 sound/usb/card.c:1030 usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_set_configuration+0x1187/0x1e50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5529 Comm: kworker/0:8 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:prep_compound_page+0x67/0x480 mm/page_alloc.c:720 Code: 3c 02 00 0f 85 e0 03 00 00 49 8b 04 24 48 83 f8 ff 0f 84 de 02 00 00 be 08 00 00 00 4c 89 e7 e8 8f 26 0a 00 49 0f ba 2c 24 06 <83> fd 01 0f 8e d4 02 00 00 8d 45 fe 4d 8d 74 24 58 48 bd 00 00 00 RSP: 0018:ffffc9000392e748 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000003 RCX: ffffffff81d7a211 RDX: fffff940009ced41 RSI: 0000000000000008 RDI: ffffea0004e76a00 RBP: 0000000000000008 R08: 0000000000000001 R09: fffff940009ced40 R10: ffffea0004e76a07 R11: ffff88811e9ca7e8 R12: ffffea0004e76a00 R13: 0000000000000003 R14: 0000000000040000 R15: ffff88823fffa680 FS: 0000000000000000(0000) GS:ffff888268bf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee0ce56faf CR3: 000000011720a000 CR4: 00000000003506f0 Call Trace: prep_new_page mm/page_alloc.c:1857 [inline] get_page_from_freelist+0x253d/0x3cb0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x259/0x21c0 mm/page_alloc.c:5210 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe20/0x1ca0 mm/slub.c:4656 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_node_track_caller_noprof+0x498/0x8e0 mm/slub.c:5764 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:608 __alloc_skb+0x186/0x410 net/core/skbuff.c:690 __netdev_alloc_skb+0x7a/0x920 net/core/skbuff.c:754 netdev_alloc_skb include/linux/skbuff.h:3484 [inline] dev_alloc_skb include/linux/skbuff.h:3497 [inline] ath6kl_usb_post_recv_transfers.constprop.0+0x55/0x400 drivers/net/wireless/ath/ath6kl/usb.c:428 ath6kl_usb_start_recv_pipes drivers/net/wireless/ath/ath6kl/usb.c:498 [inline] hif_start drivers/net/wireless/ath/ath6kl/usb.c:703 [inline] ath6kl_usb_power_on+0x8e/0x160 drivers/net/wireless/ath/ath6kl/usb.c:1062 ath6kl_hif_power_on drivers/net/wireless/ath/ath6kl/hif-ops.h:136 [inline] ath6kl_core_init+0x17e/0x11b0 drivers/net/wireless/ath/ath6kl/core.c:97 ath6kl_usb_probe+0xcee/0x1440 drivers/net/wireless/ath/ath6kl/usb.c:1168 usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_set_configuration+0x1187/0x1e50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 ---------------- Code disassembly (best guess): 0: 89 ff mov %edi,%edi 2: 48 89 fd mov %rdi,%rbp 5: eb 0c jmp 0x13 7: 48 8d 6b 04 lea 0x4(%rbx),%rbp b: 49 89 df mov %rbx,%r15 e: 49 39 ec cmp %rbp,%r12 11: 72 4e jb 0x61 13: 4c 89 e2 mov %r12,%rdx 16: 48 29 ea sub %rbp,%rdx 19: 48 89 d6 mov %rdx,%rsi 1c: 48 c1 ea 3f shr $0x3f,%rdx 20: 48 c1 fe 02 sar $0x2,%rsi 24: 48 01 f2 add %rsi,%rdx 27: 48 d1 fa sar %rdx * 2a: 48 8d 5c 95 00 lea 0x0(%rbp,%rdx,4),%rbx <-- trapping instruction 2f: 48 89 da mov %rbx,%rdx 32: 48 c1 ea 03 shr $0x3,%rdx 36: 0f b6 34 0a movzbl (%rdx,%rcx,1),%esi 3a: 48 89 da mov %rbx,%rdx 3d: 83 e2 07 and $0x7,%edx