INFO: task kworker/u4:2:34 blocked for more than 143 seconds. Not tainted 5.10.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:12368 pid: 34 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x450/0x940 kernel/sched/core.c:5078 schedule+0x38/0xe0 kernel/sched/core.c:5157 schedule_timeout+0x275/0x360 kernel/time/timer.c:1854 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+0xae/0x110 kernel/sched/completion.c:138 kthread_park+0x43/0x80 kernel/kthread.c:557 io_sq_thread_park fs/io_uring.c:7345 [inline] io_sq_thread_stop+0x46/0x150 fs/io_uring.c:7366 io_finish_async fs/io_uring.c:7384 [inline] io_ring_ctx_free fs/io_uring.c:8551 [inline] io_ring_exit_work+0x40/0x220 fs/io_uring.c:8643 process_one_work+0x293/0x600 kernel/workqueue.c:2275 worker_thread+0x38/0x380 kernel/workqueue.c:2421 kthread+0x144/0x170 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/u4:2/34: #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 #1: ffffc90000d73e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #1: ffffc90000d73e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #1: ffffc90000d73e70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 #2: ffff88811eb64e70 (&sqd->lock){+.+.}-{3:3}, at: io_sq_thread_park.part.66+0xf/0x20 fs/io_uring.c:7347 1 lock held by khungtaskd/1613: #0: ffffffff84e17880 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x17a kernel/locking/lockdep.c:6255 1 lock held by in:imklog/8043: #0: ffff8881098860f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x45/0x50 fs/file.c:947 2 locks held by kworker/u4:6/10216: #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 #1: ffffc90002b1be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #1: ffffc90002b1be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #1: ffffc90002b1be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 2 locks held by kworker/u4:7/10361: #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 #1: ffffc90002d7be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #1: ffffc90002d7be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #1: ffffc90002d7be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 2 locks held by kworker/u4:9/10599: #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888100058938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 #1: ffffc9000312be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #1: ffffc9000312be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #1: ffffc9000312be70 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x207/0x600 kernel/workqueue.c:2246 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1613 Comm: khungtaskd Not tainted 5.10.0-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+0x77/0x97 lib/dump_stack.c:120 nmi_cpu_backtrace.cold.8+0x53/0x6d lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0xd5/0xf0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0x57f/0x670 kernel/hung_task.c:294 kthread+0x144/0x170 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8248 Comm: io_uring-sq Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lock_is_held_type+0xea/0x120 kernel/locking/lockdep.c:5481 Code: 83 e0 03 39 c8 41 0f 94 c5 48 c7 c7 34 99 6a 84 e8 db 09 00 00 ba ff ff ff ff 65 0f c1 15 0e 64 97 7c 83 fa 01 75 1a 41 57 9d <48> 83 c4 08 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 ed eb RSP: 0018:ffffc9000c5fbdf0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff846a9934 RDI: ffffffff847b1fae RBP: ffffffff84e17840 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881456e3580 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc8786c310 CR3: 000000011ce46000 CR4: 0000000000350ee0 Call Trace: lock_is_held include/linux/lockdep.h:271 [inline] ___might_sleep+0xd3/0x140 kernel/sched/core.c:7877 io_sq_thread+0x428/0x7e0 fs/io_uring.c:7031 kthread+0x144/0x170 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296