INFO: task kworker/u4:2:73 blocked for more than 143 seconds. Not tainted 5.6.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D27880 73 2 0x80004000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: schedule+0xc4/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x56c/0x970 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x25f/0x3c0 kernel/sched/completion.c:136 __synchronize_srcu+0x18e/0x240 kernel/rcu/srcutree.c:922 fsnotify_mark_destroy_workfn+0xea/0x330 fs/notify/mark.c:832 process_one_work+0x903/0x15c0 kernel/workqueue.c:2264 worker_thread+0x82/0xb50 kernel/workqueue.c:2410 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/u4:6:512 blocked for more than 143 seconds. Not tainted 5.6.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:6 D26248 512 2 0x80004000 Workqueue: events_unbound fsnotify_connector_destroy_workfn Call Trace: schedule+0xc4/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x56c/0x970 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x25f/0x3c0 kernel/sched/completion.c:136 __synchronize_srcu+0x18e/0x240 kernel/rcu/srcutree.c:922 fsnotify_connector_destroy_workfn+0x40/0xa0 fs/notify/mark.c:164 process_one_work+0x903/0x15c0 kernel/workqueue.c:2264 worker_thread+0x82/0xb50 kernel/workqueue.c:2410 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 2 locks held by kworker/u4:2/73: #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: process_one_work+0x80f/0x15c0 kernel/workqueue.c:2235 #1: ffffc90001037e00 ((reaper_work).work){+.+.}, at: process_one_work+0x844/0x15c0 kernel/workqueue.c:2239 2 locks held by kworker/u4:6/512: #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa433928 ((wq_completion)events_unbound){+.+.}, at: process_one_work+0x80f/0x15c0 kernel/workqueue.c:2235 #1: ffffc90001de7e00 (connector_reaper_work){+.+.}, at: process_one_work+0x844/0x15c0 kernel/workqueue.c:2239 1 lock held by khungtaskd/1121: #0: ffffffff88ba63c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x52/0x28d kernel/locking/lockdep.c:5331 6 locks held by kworker/0:2/2666: 6 locks held by kworker/1:9/2681: 6 locks held by kworker/1:11/2698: 1 lock held by in:imklog/6560: #0: ffff8880a2206620 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x96/0xb0 fs/file.c:821 4 locks held by systemd-udevd/8431: #0: ffff888094b14f40 (&p->lock){+.+.}, at: seq_read+0x66/0x1010 fs/seq_file.c:161 #1: ffff8880a8d89880 (&of->mutex){+.+.}, at: kernfs_seq_start+0x44/0x160 fs/kernfs/file.c:111 #2: ffff8880a95900e8 (kn->count#68){.+.+}, at: kernfs_seq_start+0x6e/0x160 fs/kernfs/file.c:112 #3: ffff8880a4501200 (&dev->mutex){....}, at: device_lock_interruptible include/linux/device.h:776 [inline] #3: ffff8880a4501200 (&dev->mutex){....}, at: serial_show+0x1b/0x80 drivers/usb/core/sysfs.c:142 4 locks held by systemd-udevd/8434: #0: ffff8880a4420760 (&p->lock){+.+.}, at: seq_read+0x66/0x1010 fs/seq_file.c:161 #1: ffff888094f18480 (&of->mutex){+.+.}, at: kernfs_seq_start+0x44/0x160 fs/kernfs/file.c:111 #2: ffff8880a8dc4468 (kn->count#68){.+.+}, at: kernfs_seq_start+0x6e/0x160 fs/kernfs/file.c:112 #3: ffff8880a4bfd200 (&dev->mutex){....}, at: device_lock_interruptible include/linux/device.h:776 [inline] #3: ffff8880a4bfd200 (&dev->mutex){....}, at: serial_show+0x1b/0x80 drivers/usb/core/sysfs.c:142 4 locks held by systemd-udevd/8441: #0: ffff8880a35b1640 (&p->lock){+.+.}, at: seq_read+0x66/0x1010 fs/seq_file.c:161 #1: ffff8880a6fd3480 (&of->mutex){+.+.}, at: kernfs_seq_start+0x44/0x160 fs/kernfs/file.c:111 #2: ffff8880a6d68e08 (kn->count#68){.+.+}, at: kernfs_seq_start+0x6e/0x160 fs/kernfs/file.c:112 #3: ffff88809cc0f200 (&dev->mutex){....}, at: device_lock_interruptible include/linux/device.h:776 [inline] #3: ffff88809cc0f200 (&dev->mutex){....}, at: serial_show+0x1b/0x80 drivers/usb/core/sysfs.c:142 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1121 Comm: khungtaskd Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x128/0x182 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.7+0x4b/0x83 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x183/0x1ac lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x629/0xc70 kernel/hung_task.c:289 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2666 Comm: kworker/0:2 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:hid_apply_multiplier drivers/hid/hid-core.c:1107 [inline] RIP: 0010:hid_setup_resolution_multiplier+0x30e/0xc80 drivers/hid/hid-core.c:1163 Code: c0 03 38 d0 7c 08 84 d2 0f 85 8d 07 00 00 41 83 7f 04 02 74 65 4d 89 c5 eb 2c 49 8d 7f 04 48 89 f8 48 c1 e8 03 42 0f b6 14 08 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 e9 05 00 00 41 RSP: 0018:ffffc90007f6ec70 EFLAGS: 00000a07 RAX: 1ffff110141ae100 RBX: ffff888082020000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a0d70804 RBP: 0000000000000000 R08: ffff8880a2868000 R09: dffffc0000000000 R10: 0000000000000323 R11: ffffc900044e40db R12: ffff8880a0d70800 R13: ffff8880a2868000 R14: ffffc900044c9000 R15: ffff8880a0d70800 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f77d348c000 CR3: 000000008f2f4000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hid_open_report+0x3b3/0x5d0 drivers/hid/hid-core.c:1274 hid_parse include/linux/hid.h:1017 [inline] ms_probe+0xeb/0x460 drivers/hid/hid-microsoft.c:388 hid_device_probe+0x260/0x350 drivers/hid/hid-core.c:2263 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 hid_add_device+0x2da/0x8b0 drivers/hid/hid-core.c:2419 usbhid_probe+0x9b5/0xe40 drivers/hid/usbhid/hid-core.c:1386 usb_probe_interface+0x268/0x6c0 drivers/usb/core/driver.c:361 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 usb_set_configuration+0xc02/0x1560 drivers/usb/core/message.c:2023 generic_probe+0x61/0x8a drivers/usb/core/generic.c:210 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 usb_new_device.cold.66+0x679/0xe85 drivers/usb/core/hub.c:2548 hub_port_connect drivers/usb/core/hub.c:5195 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x15fe/0x2d60 drivers/usb/core/hub.c:5563 process_one_work+0x903/0x15c0 kernel/workqueue.c:2264 worker_thread+0x82/0xb50 kernel/workqueue.c:2410 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352