INFO: task kworker/u4:4:374 blocked for more than 143 seconds. Not tainted 5.11.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:25664 pid: 374 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_timeout+0x1d8/0x250 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+0x163/0x260 kernel/sched/completion.c:138 kthread_park+0x122/0x1b0 kernel/kthread.c:582 io_sq_thread_park fs/io_uring.c:7469 [inline] io_sq_thread_park fs/io_uring.c:7463 [inline] io_sq_thread_stop+0xfe/0x570 fs/io_uring.c:7487 io_finish_async fs/io_uring.c:7505 [inline] io_ring_ctx_free fs/io_uring.c:8670 [inline] io_ring_exit_work+0x62/0x6d0 fs/io_uring.c:8763 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 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/u4:4/374: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc9000223fda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 #2: ffff88804e779470 (&sqd->lock){+.+.}-{3:3}, at: io_sq_thread_park fs/io_uring.c:7468 [inline] #2: ffff88804e779470 (&sqd->lock){+.+.}-{3:3}, at: io_sq_thread_park fs/io_uring.c:7463 [inline] #2: ffff88804e779470 (&sqd->lock){+.+.}-{3:3}, at: io_sq_thread_stop+0xd6/0x570 fs/io_uring.c:7487 1 lock held by khungtaskd/1658: #0: ffffffff8bd73da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6259 2 locks held by systemd-journal/4878: 1 lock held by systemd-udevd/4890: #0: ffff8880b9c34c58 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1320 [inline] #0: ffff8880b9c34c58 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x217/0x21a0 kernel/sched/core.c:4995 1 lock held by in:imklog/8276: #0: ffff88802475ad70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 2 locks held by kworker/1:3/8262: #0: ffff888010c7c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c7c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010c7c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010c7c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010c7c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010c7c538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc9000c9e7da8 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 1 lock held by syz-executor.0/8464: #0: ffff888147488d88 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 1 lock held by syz-executor.1/8466: #0: ffff888147488d88 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 1 lock held by syz-executor.2/8468: #0: ffff888147488d88 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 2 locks held by syz-executor.3/8470: #0: ffff888147488d88 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 #1: ffffffff8bd7c668 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8bd7c668 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f2/0x610 kernel/rcu/tree_exp.h:836 1 lock held by syz-executor.4/8472: #0: ffff888147488d88 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 1 lock held by syz-executor.5/8474: #0: ffff888147488d88 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x41/0x540 net/netfilter/x_tables.c:1206 2 locks held by systemd-udevd/28920: #0: ffff88802349a460 (sb_writers#3){.+.+}-{0:0}, at: do_unlinkat+0x190/0x660 fs/namei.c:3881 #1: ffff888013f0de90 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:808 [inline] #1: ffff888013f0de90 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: lock_rename+0x225/0x280 fs/namei.c:2758 2 locks held by systemd-udevd/28946: 1 lock held by systemd-udevd/29461: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1658 Comm: khungtaskd Not tainted 5.11.0-rc6-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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd43/0xfa0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 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: 4878 Comm: systemd-journal Not tainted 5.11.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:sched_idle_cpu kernel/sched/fair.c:5485 [inline] RIP: 0010:select_idle_smt kernel/sched/fair.c:6118 [inline] RIP: 0010:select_idle_sibling kernel/sched/fair.c:6326 [inline] RIP: 0010:select_task_rq_fair+0x2184/0x3360 kernel/sched/fair.c:6770 Code: 00 00 00 4d 63 e7 48 c7 c5 40 4c 03 00 49 83 fc 07 0f 87 a1 0d 00 00 4a 8d 3c e5 c0 f6 e6 8a 48 89 fa 48 c1 ea 03 80 3c 1a 00 <0f> 85 7e 0d 00 00 4a 03 2c e5 c0 f6 e6 8a 48 8d 7d 40 48 89 f8 48 RSP: 0018:ffffc90000db0ca0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff8150fb1a RDX: 1ffffffff15cded8 RSI: 0000000000000008 RDI: ffffffff8ae6f6c0 RBP: 0000000000034c40 R08: 0000000000000000 R09: ffff888011a5051f R10: ffffed100234a0a3 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fd158e898c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7744032b80 CR3: 0000000025959000 CR4: 0000000000350ee0 Call Trace: select_task_rq kernel/sched/core.c:2815 [inline] try_to_wake_up+0x368/0x14a0 kernel/sched/core.c:3453 hrtimer_wakeup+0x43/0x60 kernel/time/hrtimer.c:1773 __run_hrtimer kernel/time/hrtimer.c:1519 [inline] __hrtimer_run_queues+0x609/0xe40 kernel/time/hrtimer.c:1583 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1102 asm_call_irq_on_stack+0xf/0x20 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline] run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline] sysvec_apic_timer_interrupt+0xbd/0x100 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:629 RIP: 0010:devkmsg_read+0x3da/0x740 kernel/printk/printk.c:754 Code: 01 80 3c 02 00 0f 85 19 03 00 00 48 c7 c7 00 2f d6 8b 4c 89 6d 00 e8 45 ba a1 07 e8 d0 48 00 00 e8 6b 79 1d 00 fb 48 8b 2c 24 <4c> 89 ff 48 c7 c3 ea ff ff ff 48 89 ee e8 e4 ac 17 00 49 39 ef 77 RSP: 0018:ffffc90000edfd68 EFLAGS: 00000202 RAX: 0000000000217efb RBX: ffff888026a320f8 RCX: ffffffff81585217 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000002000 R08: 0000000000000001 R09: ffffffff8f86684f R10: fffffbfff1f0cd09 R11: 000000000000005c R12: 1ffff920001dbfb2 R13: 0000000000001f1c R14: ffff888026a30068 R15: 0000000000000041 vfs_read+0x1b5/0x570 fs/read_write.c:494 ksys_read+0x12d/0x250 fs/read_write.c:634 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fd158418210 Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24 RSP: 002b:00007ffc438561c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007ffc43858c40 RCX: 00007fd158418210 RDX: 0000000000002000 RSI: 00007ffc43856a40 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000008 R09: 00007ffc438600f0 R10: 000000000002cc12 R11: 0000000000000246 R12: 00007ffc43856a40 R13: 00007ffc43858b98 R14: 000056281db17958 R15: 0005ba9fb0f8883c