INFO: task systemd-shutdow:1 blocked for more than 143 seconds.
      Not tainted 5.12.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:systemd-shutdow state:D stack:23032 pid:    1 ppid:     0 flags:0x00000000
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x91b/0x1f90 kernel/sched/core.c:5075
 schedule+0xcb/0x270 kernel/sched/core.c:5154
 wait_for_device_probe+0x1be/0x220 drivers/base/dd.c:704
 device_shutdown+0x18/0x5c0 drivers/base/core.c:4313
 kernel_restart_prepare kernel/reboot.c:76 [inline]
 kernel_restart+0x61/0xa0 kernel/reboot.c:246
 __do_sys_reboot+0x31e/0x3e0 kernel/reboot.c:349
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fd62f0248c6
RSP: 002b:00007fffc3aa6cb8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a9
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd62f0248c6
RDX: 0000000001234567 RSI: 0000000028121969 RDI: fffffffffee1dead
RBP: 00007fffc3aa6d48 R08: 0000000000002800 R09: 0000000000000005
R10: 0000000000000002 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 000055d96df8a150 R15: 00007fffc3aa7038

Showing all locks held in the system:
1 lock held by systemd-shutdow/1:
 #0: ffffffff87952c68 (system_transition_mutex){+.+.}-{3:3}, at: __do_sys_reboot+0x1a3/0x3e0 kernel/reboot.c:346
1 lock held by khungtaskd/1275:
 #0: ffffffff87a783a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:6327
9 locks held by kworker/0:5/7349:
 #0: ffff888103ecf938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888103ecf938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888103ecf938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888103ecf938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888103ecf938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888103ecf938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x871/0x1580 kernel/workqueue.c:2246
 #1: ffffc90004bb7da8
 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1580 kernel/workqueue.c:2250
 #2: ffff888108e94218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:740 [inline]
 #2: ffff888108e94218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4320 drivers/usb/core/hub.c:5537
 #3: ffff888100d22218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:740 [inline]
 #3: ffff888100d22218 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:889
 #4: ffff888134c7c1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:740 [inline]
 #4: ffff888134c7c1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:889
 #5: ffff8881041dcc60 (&dev->phy_mutex){+.+.}-{3:3}, at: asix_mdio_read+0x9a/0x320 drivers/net/usb/asix_common.c:452
 #6: 
ffff8881f6a332d8 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1321 [inline]
ffff8881f6a332d8 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x230/0x1f90 kernel/sched/core.c:4992
 #7: ffffffff8a645790
 (&obj_hash[i].lock){-.-.}-{2:2}, at: cpu_of kernel/sched/sched.h:1086 [inline]
 (&obj_hash[i].lock){-.-.}-{2:2}, at: __update_idle_core+0x39/0x440 kernel/sched/fair.c:6045
 #8: ffffffff879887b8 (console_owner_lock){..-.}-{2:2}, at: console_lock_spinning_disable_and_check kernel/printk/printk.c:1736 [inline]
 #8: ffffffff879887b8 (console_owner_lock){..-.}-{2:2}, at: console_unlock+0x68e/0xc60 kernel/printk/printk.c:2579

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

NMI backtrace for cpu 1
CPU: 1 PID: 1275 Comm: khungtaskd Not tainted 5.12.0-rc2-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+0x143/0x1db lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x46/0xe0 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1da/0x200 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+0xd32/0xf70 kernel/hung_task.c:294
 kthread+0x38c/0x460 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x1c9/0x250 drivers/acpi/processor_idle.c:516