INFO: task kworker/0:2:2544 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:21256 pid:2544 tgid:2544 ppid:2 task_flags:0x4288060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xeb1/0x41f0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7004 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121 __flush_work+0x7c7/0xcb0 kernel/workqueue.c:4327 __cancel_work_sync kernel/workqueue.c:4447 [inline] cancel_delayed_work_sync+0xd1/0xf0 kernel/workqueue.c:4521 quiesce_and_remove_host drivers/usb/storage/usb.c:939 [inline] usb_stor_disconnect+0xc5/0x270 drivers/usb/storage/usb.c:1186 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:573 [inline] device_remove+0x12a/0x180 drivers/base/dd.c:565 __device_release_driver drivers/base/dd.c:1284 [inline] device_release_driver_internal+0x42e/0x600 drivers/base/dd.c:1307 bus_remove_device+0x22f/0x440 drivers/base/bus.c:616 device_del+0x376/0x9b0 drivers/base/core.c:3878 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1418 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/0:0/9: 2 locks held by kworker/u8:0/12: #0: ffff8881000ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900000cfd18 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 1 lock held by kworker/R-mm_pe/13: 3 locks held by kworker/1:0/23: 2 locks held by kworker/1:1/28: #0: ffff88810006b548 ((wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900001e7d18 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 1 lock held by khungtaskd/30: #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:2/37: #0: ffff8881000ac948 ((wq_completion)events_unbound#2){+.+.}-{0:0} , at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90000277d18 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 5 locks held by kworker/0:2/2544: #0: ffff888105e99148 ((wq_completion)usb_hub_wq){+.+.}-{0:0} , at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90004befd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88810b7b9198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88810b7b9198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88813df19198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88813df19198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff888120f3e160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff888120f3e160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1106 [inline] #4: ffff888120f3e160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xaa/0x600 drivers/base/dd.c:1304 1 lock held by udevd/2851: #0: ffff888101298188 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185 2 locks held by getty/2914: #0: ffff888112a140a0 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 ( &ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by udevd/5198: #0: ffff888101298188 ( &root->kernfs_rwsem){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185 5 locks held by kworker/0:3/5218: 4 locks held by udevd/5235: #0: ffff888133eb1668 ( &p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff888134873888 ( &of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888133092698 ( kn->active #9 ){++++}-{0:0} , at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] , at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff888121439198 ( &dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:900 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/5236: #0: ffff888133eb1c30 ( &p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff8881134ca488 (