INFO: task systemd-shutdow:1 blocked for more than 143 seconds. Not tainted 5.9.0-rc8-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-shutdow state:D stack:24096 pid: 1 ppid: 0 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x88f/0x1f80 kernel/sched/core.c:4527 schedule+0xcd/0x2b0 kernel/sched/core.c:4602 wait_for_device_probe+0x1be/0x220 drivers/base/dd.c:702 device_shutdown+0x18/0x5b5 drivers/base/core.c:3994 kernel_restart_prepare kernel/reboot.c:76 [inline] kernel_restart kernel/reboot.c:246 [inline] __do_sys_reboot.cold+0x5d/0x9d kernel/reboot.c:347 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f7771d418c6 Code: Bad RIP value. RSP: 002b:00007fffb908be98 EFLAGS: 00000202 ORIG_RAX: 00000000000000a9 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7771d418c6 RDX: 0000000001234567 RSI: 0000000028121969 RDI: fffffffffee1dead RBP: 00007fffb908bf28 R08: 0000000000005001 R09: 0000000000000005 R10: 0000000000000002 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 000055b0bc7c9150 R15: 00007fffb908c218 Showing all locks held in the system: 1 lock held by systemd-shutdow/1: #0: ffffffff872ea808 (system_transition_mutex){+.+.}-{3:3}, at: __do_sys_reboot+0x1a4/0x3e0 kernel/reboot.c:344 1 lock held by khungtaskd/23: #0: ffffffff87313c20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5852 5 locks held by kworker/1:4/3072: #0: ffff8881d885a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d885a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881d885a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881d885a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881d885a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881d885a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240 #1: ffff8881cce0fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244 #2: ffff8881d451a218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:785 [inline] #2: ffff8881d451a218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x42b0 drivers/usb/core/hub.c:5536 #3: ffff8881ce767218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:785 [inline] #3: ffff8881ce767218 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:887 #4: ffff8881c5e4a1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:785 [inline] #4: ffff8881c5e4a1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:887 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.9.0-rc8-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+0x107/0x16e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x74/0xb6 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1da/0x1f4 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+0xd6a/0xfd0 kernel/hung_task.c:295 kthread+0x392/0x470 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:match_held_lock+0xa/0x150 kernel/locking/lockdep.c:4503 Code: 66 55 02 85 c0 75 cd 48 c7 c6 40 fa 06 86 48 c7 c7 80 fa 06 86 e8 08 f8 5d fb 0f 0b c3 0f 1f 00 48 39 77 10 0f 84 97 00 00 00 <66> f7 47 22 f0 ff 74 4b 48 83 ec 08 48 8b 46 08 48 85 c0 0f 84 84 RSP: 0018:ffff8881db309da0 EFLAGS: 00000012 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000fff5547e RDX: 0000000000000000 RSI: ffffffff872f64c8 RDI: ffff8881da23bb20 RBP: ffff8881da23b280 R08: 0000000000000000 R09: ffffffff895cb5e7 R10: ffffffff8121b410 R11: 0000000000000000 R12: ffffffff872f64c8 R13: ffff8881da23bb20 R14: 00000000ffffffff R15: ffff8881da23bb20 FS: 0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f777232d730 CR3: 0000000007224000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held kernel/locking/lockdep.c:4794 [inline] lock_is_held_type+0x6e/0xe0 kernel/locking/lockdep.c:5068 lock_is_held include/linux/lockdep.h:267 [inline] rebalance_domains+0x75f/0xcf0 kernel/sched/fair.c:9922 _nohz_idle_balance+0x3e8/0x4f0 kernel/sched/fair.c:10385 __do_softirq+0x1af/0x92c kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x71/0x90 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x110/0x1a0 kernel/softirq.c:435 sysvec_call_function_single+0x43/0x90 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:589 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:79 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:169 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline] RIP: 0010:acpi_idle_do_entry+0x1c9/0x250 drivers/acpi/processor_idle.c:517 Code: 4d 5c 88 fb 84 db 75 ac e8 d4 63 88 fb e8 7f 01 8e fb e9 0c 00 00 00 e8 c5 63 88 fb 0f 00 2d 5e 1c 6d 00 e8 b9 63 88 fb fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 74 5c 88 fb 48 85 db RSP: 0018:ffff8881da257d20 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff1016c01 RDX: ffff8881da23b280 RSI: ffffffff85b7ae07 RDI: ffffffff85b7adf1 RBP: ffff8881d8d62064 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: ffff8881d8d62000 R14: ffff8881d8d62064 R15: ffff8881d6ee1004 acpi_idle_enter+0x337/0x490 drivers/acpi/processor_idle.c:648 cpuidle_enter_state+0x19e/0xa10 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:350 call_cpuidle kernel/sched/idle.c:132 [inline] cpuidle_idle_call kernel/sched/idle.c:213 [inline] do_idle+0x3d5/0x580 kernel/sched/idle.c:273 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:369 start_secondary+0x25b/0x320 arch/x86/kernel/smpboot.c:266 secondary_startup_64+0xb6/0xc0 arch/x86/kernel/head_64.S:243