INFO: task kworker/1:0:27983 blocked for more than 143 seconds. Not tainted 5.8.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:0 I26648 27983 2 0x00004000 Workqueue: 0x0 (events) Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 worker_thread+0x14c/0x1120 kernel/workqueue.c:2436 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 1 lock held by khungtaskd/1164: #0: ffffffff89bd62c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5825 1 lock held by in:imklog/6730: #0: ffff8880a16a1130 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 1 lock held by rs:main Q:Reg/6731: #0: ffff8880ae735e58 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae735e58 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x232/0x21e0 kernel/sched/core.c:4445 2 locks held by kworker/0:3/7517: #0: ffff8880aa066d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa066d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880aa066d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880aa066d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880aa066d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880aa066d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90015c7fda8 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 3 locks held by kworker/0:4/7722: 2 locks held by kworker/1:5/12786: #0: ffff8880aa076538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa076538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880aa076538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880aa076538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880aa076538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880aa076538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90001ddfda8 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 2 locks held by syz-executor.3/3074: #0: ffffffff8a7dea48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:705 [inline] #0: ffffffff8a7dea48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3408 #1: ffffffff89bda928 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #1: ffffffff89bda928 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x274/0x5f0 kernel/rcu/tree_exp.h:838 1 lock held by syz-executor.4/3080: #0: ffffffff8a7dea48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:705 [inline] #0: ffffffff8a7dea48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3408 3 locks held by syz-executor.2/3084: #0: ffff88806bca8f40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xf5/0x1080 net/bluetooth/hci_core.c:1720 #1: ffff88806bca8078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x253/0x1080 net/bluetooth/hci_core.c:1757 #2: ffffffff8a90ca68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1435 [inline] #2: ffffffff8a90ca68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xc7/0x220 net/bluetooth/hci_conn.c:1557 3 locks held by syz-executor.1/3094: #0: ffff888094d8cf40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xf5/0x1080 net/bluetooth/hci_core.c:1720 #1: ffff888094d8c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x253/0x1080 net/bluetooth/hci_core.c:1757 #2: ffffffff8a90ca68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1435 [inline] #2: ffffffff8a90ca68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xc7/0x220 net/bluetooth/hci_conn.c:1557 3 locks held by syz-executor.5/3119: #0: ffff88806040cf40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xf5/0x1080 net/bluetooth/hci_core.c:1720 #1: ffff88806040c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x253/0x1080 net/bluetooth/hci_core.c:1757 #2: ffffffff8a90ca68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1435 [inline] #2: ffffffff8a90ca68 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xc7/0x220 net/bluetooth/hci_conn.c:1557 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1164 Comm: khungtaskd Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 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+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3193 Comm: (d-rfkill) Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:exit_to_user_mode kernel/entry/common.c:108 [inline] RIP: 0010:syscall_exit_to_user_mode+0x74/0x2b0 kernel/entry/common.c:243 Code: 00 00 e8 0f 0b 8a f9 48 89 ef e8 a7 06 73 f9 e8 22 08 8a f9 48 8b 7c 24 20 e8 08 0e 6a f9 0f 1f 44 00 00 0f 00 2d cc 37 5d 00 <48> 8b 7c 24 20 5b 5d 41 5c 41 5d e9 5c f4 ff ff 0f 0b 48 63 f6 48 RSP: 0018:ffffc90002217f30 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff1562951 RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffff88805e14ee8c RBP: ffffc90002217f58 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f7e4aa68500(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f38414f0000 CR3: 0000000092a68000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f7e4930628d Code: c1 20 00 00 75 10 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 37 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffc79054f70 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: fffffffffffffff7 RBX: 000000000000c37d RCX: 00007f7e4930628d RDX: 00007ffc79054ff8 RSI: 00007ffc79054ff0 RDI: 000000000000c37d RBP: 0000000000100000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000293 R12: 0000000000000002 R13: 00007ffc79054ff0 R14: 0000000000000000 R15: 00007ffc79055270