INFO: task kworker/u4:1:21 blocked for more than 143 seconds. Not tainted 5.10.0-rc4-next-20201118-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack:24856 pid: 21 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4269 [inline] __schedule+0x890/0x2030 kernel/sched/core.c:5019 schedule+0xcf/0x270 kernel/sched/core.c:5098 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1847 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x163/0x260 kernel/sched/completion.c:138 kthread_stop+0x17a/0x720 kernel/kthread.c:596 io_put_sq_data fs/io_uring.c:7235 [inline] io_sq_thread_stop+0x452/0x570 fs/io_uring.c:7332 io_finish_async fs/io_uring.c:7339 [inline] io_ring_ctx_free fs/io_uring.c:8494 [inline] io_ring_exit_work+0x102/0x7a0 fs/io_uring.c:8588 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Showing all locks held in the system: 3 locks held by kworker/0:1/7: #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc90000cc7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 #2: ffff88814456f218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:731 [inline] #2: ffff88814456f218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x42d0 drivers/usb/core/hub.c:5537 2 locks held by kworker/u4:1/21: #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc90000dbfda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 2 locks held by kworker/u4:2/26: #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc90000e0fda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 1 lock held by khungtaskd/1656: #0: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6252 5 locks held by kworker/1:2/3085: #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc900022b7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 #2: ffff888144587218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:731 [inline] #2: ffff888144587218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x42d0 drivers/usb/core/hub.c:5537 #3: ffffffff8b32aea0 (console_lock){+.+.}-{0:0}, at: rq_lock kernel/sched/sched.h:1318 [inline] ffffffff8b32aea0 (console_lock){+.+.}-{0:0}, at: __schedule+0x217/0x2030 kernel/sched/core.c:4936 #4: ffff8880b9f34f98 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1318 [inline] #4: ffff8880b9f34f98 (&rq->lock){-.-.}-{2:2}, at: attach_tasks kernel/sched/fair.c:7825 [inline] #4: ffff8880b9f34f98 (&rq->lock){-.-.}-{2:2}, at: load_balance+0xc93/0x2ce0 kernel/sched/fair.c:9637 1 lock held by systemd-journal/4895: 1 lock held by in:imklog/8199: #0: ffff888011f4b770 ( &f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:932 2 locks held by kworker/u4:8/17620: #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc90016487da8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 3 locks held by kworker/1:10/20733: #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rq_lock kernel/sched/sched.h:1318 [inline] ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: __schedule+0x217/0x2030 kernel/sched/core.c:4936 #1: ffff8880b9f20088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833 #2: ffff888020ea4ce0 (&r->consumer_lock#2){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:359 [inline] #2: ffff888020ea4ce0 (&r->consumer_lock#2){+...}-{2:2}, at: ptr_ring_consume_bh include/linux/ptr_ring.h:365 [inline] #2: ffff888020ea4ce0 (&r->consumer_lock#2){+...}-{2:2}, at: wg_packet_encrypt_worker+0xda/0xf10 drivers/net/wireguard/send.c:297 3 locks held by kworker/0:0/5899: #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffff8880b9e20088 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833 #2: ffff8880b9e24730 (krc.lock){..-.}-{2:2}, at: kfree_rcu_monitor+0x15/0x80 kernel/rcu/tree.c:3371 2 locks held by kworker/u4:6/19153: #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc900173bfda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 3 locks held by kworker/0:4/28609: 3 locks held by kworker/1:3/30149: #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888015055538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2243 #1: ffffc90009e7fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2247 #2: ffff88814455f218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:731 [inline] #2: ffff88814455f218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x42d0 drivers/usb/core/hub.c:5537 1 lock held by systemd-udevd/2035: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1656 Comm: khungtaskd Not tainted 5.10.0-rc4-next-20201118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:338 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 20608 Comm: kworker/u4:3 Not tainted 5.10.0-rc4-next-20201118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:mark_lock+0x12e/0x24c0 kernel/locking/lockdep.c:4387 Code: 00 4f 8d 6c 6d 00 49 c1 e5 06 49 81 c5 80 0b bc 8e 49 8d 7d 50 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 fd 18 00 00 4c 89 f0 49 23 45 50 41 bf 01 00 00 00 0f 84 7d RSP: 0018:ffffc90002567908 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 1ffff920004acf28 RCX: ffffffff815602b7 RDX: 1ffffffff1d7859a RSI: 0000000000000008 RDI: ffffffff8ebc2cd0 RBP: ffff8880208223f8 R08: 0000000000000000 R09: ffffffff8ebc0767 R10: fffffbfff1d780ec R11: 0000000000000000 R12: 0000000000000009 R13: ffffffff8ebc2c80 R14: 0000000000000200 R15: ffff8880208223a8 FS: 0000000000000000(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9312bcf000 CR3: 0000000025e33000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4330 [inline] __lock_acquire+0x8c1/0x5c00 kernel/locking/lockdep.c:4784 lock_acquire kernel/locking/lockdep.c:5435 [inline] lock_acquire+0x2a3/0x8c0 kernel/locking/lockdep.c:5400 rcu_lock_acquire include/linux/rcupdate.h:255 [inline] rcu_read_lock include/linux/rcupdate.h:644 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:718 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296