INFO: task systemd-shutdow:1 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:systemd-shutdow state:D stack:24456 pid:    1 ppid:     0 flags:0x00000000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x889/0x1f70 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:3998
 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: 0033:0x7f9f8d8fb8c6
Code: Bad RIP value.
RSP: 002b:00007ffcbb2fff78 EFLAGS: 00000206 ORIG_RAX: 00000000000000a9
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9f8d8fb8c6
RDX: 0000000001234567 RSI: 0000000028121969 RDI: fffffffffee1dead
RBP: 00007ffcbb300008 R08: 0000000000000028 R09: 0000000000000005
R10: 0000000000000002 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 000055a6103c4150 R15: 00007ffcbb3002f8

Showing all locks held in the system:
1 lock held by systemd-shutdow/1:
 #0: ffffffff872ea248 (system_transition_mutex){+.+.}-{3:3}, at: __do_sys_reboot+0x1a4/0x3e0 kernel/reboot.c:344
1 lock held by khungtaskd/23:
 #0: ffffffff87313620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5825
5 locks held by kworker/0:3/126:
 #0: ffff8881d886a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d886a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff8881d886a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff8881d886a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff8881d886a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff8881d886a938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x82b/0x15f0 kernel/workqueue.c:2240
 #1: ffff8881cf58fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x85f/0x15f0 kernel/workqueue.c:2244
 #2: ffff8881d4bf4218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:784 [inline]
 #2: ffff8881d4bf4218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c5/0x4390 drivers/usb/core/hub.c:5522
 #3: ffff8881d261e218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:784 [inline]
 #3: ffff8881d261e218 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:887
 #4: ffff8881d656d1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:784 [inline]
 #4: ffff8881d656d1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:887

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.9.0-rc1-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+0xf6/0x16e 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:_nohz_idle_balance+0x113/0x4f0 kernel/sched/fair.c:10331
Code: 41 89 c5 4c 89 e0 48 c1 e8 03 0f b6 14 18 4c 89 e0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 06 03 00 00 44 3b 2d 21 7b e9 06 <0f> 83 16 02 00 00 44 39 6c 24 54 74 ba 44 89 ef e8 38 a2 fd ff 85
RSP: 0018:ffff8881db209ee0 EFLAGS: 00000293
RAX: 0000000000000007 RBX: dffffc0000000000 RCX: ffffffff81eb173a
RDX: 0000000000000000 RSI: ffffffff81eb1813 RDI: 0000000000000007
RBP: ffff8881db209f60 R08: 0000000000000000 R09: ffffffff880b358f
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff880b36b4
R13: 0000000000000000 R14: 0000000100015a98 R15: 0000000000000007
FS:  0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcbb2feffc CR3: 00000001d3119000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __do_softirq+0x1af/0x91c kernel/softirq.c:298
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 do_softirq_own_stack+0x73/0x90 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+0x107/0x1a0 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_irq_disable arch/x86/include/asm/irqflags.h:49 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:acpi_safe_halt+0x72/0x90 drivers/acpi/processor_idle.c:112
Code: 74 06 5b e9 40 a2 8a fb e8 3b a2 8a fb e8 26 3b 90 fb e9 0c 00 00 00 e8 2c a2 8a fb 0f 00 2d e5 62 6f 00 e8 20 a2 8a fb fb f4 <fa> e8 18 35 90 fb 5b e9 12 a2 8a fb 48 89 df e8 4a 82 b4 fb eb ab
RSP: 0018:ffffffff87207cf0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff1016041
RDX: ffffffff8722f240 RSI: ffffffff85b55ea0 RDI: ffffffff85b55e8a
RBP: ffff8881d8d71864 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8881d8d71864
R13: 1ffffffff0e40fa7 R14: ffff8881d8d71865 R15: 0000000000000001
 acpi_idle_do_entry+0x15c/0x1b0 drivers/acpi/processor_idle.c:524
 acpi_idle_enter+0x3fa/0xa50 drivers/acpi/processor_idle.c:650
 cpuidle_enter_state+0xff/0x870 drivers/cpuidle/cpuidle.c:235
 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:346
 call_cpuidle kernel/sched/idle.c:126 [inline]
 cpuidle_idle_call kernel/sched/idle.c:214 [inline]
 do_idle+0x3d6/0x5a0 kernel/sched/idle.c:276
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:372
 start_kernel+0x458/0x479 init/main.c:1048
 secondary_startup_64+0xb6/0xc0 arch/x86/kernel/head_64.S:243