INFO: task systemd-shutdow:1 blocked for more than 143 seconds. Not tainted 5.11.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-shutdow state:D stack:23312 pid: 1 ppid: 0 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x91b/0x1f90 kernel/sched/core.c:5078 schedule+0xcb/0x270 kernel/sched/core.c:5157 wait_for_device_probe+0x1be/0x220 drivers/base/dd.c:704 device_shutdown+0x18/0x5c0 drivers/base/core.c:4180 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/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f92786e78c6 RSP: 002b:00007ffc7c3efc88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a9 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f92786e78c6 RDX: 0000000001234567 RSI: 0000000028121969 RDI: fffffffffee1dead RBP: 00007ffc7c3efd18 R08: 0000000000002800 R09: 0000000000000005 R10: 0000000000000002 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 000055716ebaa150 R15: 00007ffc7c3f0008 Showing all locks held in the system: 1 lock held by systemd-shutdow/1: #0: ffffffff87952f48 (system_transition_mutex ){+.+.}-{3:3} , at: __do_sys_reboot+0x1a3/0x3e0 kernel/reboot.c:346 1 lock held by khungtaskd/1267: #0: ffffffff87a78520 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:6259 6 locks held by kworker/1:2/2606: 6 locks held by kworker/1:8/8507: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1267 Comm: khungtaskd Not tainted 5.11.0-rc5-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+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:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2606 Comm: kworker/1:2 Not tainted 5.11.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:format_decode+0xef/0xad0 lib/vsprintf.c:2351 Code: 89 de e8 a4 e0 38 ff 80 fb 01 0f 84 93 01 00 00 e8 16 da 38 ff 89 de bf 02 00 00 00 e8 8a e0 38 ff 80 fb 02 0f 84 93 06 00 00 fc d9 38 ff 4c 89 ea c6 45 00 00 48 b8 00 00 00 00 00 fc ff df RSP: 0018:ffffc90006c76698 EFLAGS: 00000093 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88810a7b1ac0 RDX: 0000000000000000 RSI: ffff88810a7b1ac0 RDI: 0000000000000003 RBP: ffffc90006c767b0 R08: 000000007fffffff R09: 0000000000000000 R10: ffffffff8206c236 R11: 0000000000000002 R12: ffffc90006c76a08 R13: ffffffff8607e7e0 R14: 1ffff92000d8ecd6 R15: ffffc90006c76848 FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f251d4d6000 CR3: 0000000007825000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0x155/0x14f0 lib/vsprintf.c:2571 sprintf+0xc0/0x100 lib/vsprintf.c:2821 print_time kernel/printk/printk.c:1250 [inline] info_print_prefix+0x248/0x340 kernel/printk/printk.c:1276 record_print_text+0x12a/0x380 kernel/printk/printk.c:1325 console_unlock+0x318/0xb90 kernel/printk/printk.c:2555 vprintk_emit+0x1be/0x4a0 kernel/printk/printk.c:2092 dev_vprintk_emit+0x36e/0x3b2 drivers/base/core.c:4301 dev_printk_emit+0xba/0xf1 drivers/base/core.c:4312 __netdev_printk+0x1c6/0x27a net/core/dev.c:11055 netdev_err+0xd7/0x109 net/core/dev.c:11107 asix_set_sw_mii drivers/net/usb/asix_common.c:278 [inline] asix_set_sw_mii drivers/net/usb/asix_common.c:272 [inline] asix_mdio_read.cold+0x61/0xa5 drivers/net/usb/asix_common.c:454 asix_phy_reset+0x104/0x170 drivers/net/usb/asix_devices.c:215 ax88172_bind+0x412/0x5d0 drivers/net/usb/asix_devices.c:272 usbnet_probe+0xb70/0x27b0 drivers/net/usb/usbnet.c:1703 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396 really_probe+0x291/0xe60 drivers/base/dd.c:554 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:740 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:846 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4a0 drivers/base/dd.c:914 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xbc4/0x1d90 drivers/base/core.c:3109 usb_set_configuration+0x113c/0x1910 drivers/usb/core/message.c:2164 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293 really_probe+0x291/0xe60 drivers/base/dd.c:554 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:740 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:846 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4a0 drivers/base/dd.c:914 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xbc4/0x1d90 drivers/base/core.c:3109 usb_new_device.cold+0x721/0x1058 drivers/usb/core/hub.c:2555 hub_port_connect drivers/usb/core/hub.c:5223 [inline] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] port_event drivers/usb/core/hub.c:5509 [inline] hub_event+0x2357/0x4320 drivers/usb/core/hub.c:5591 process_one_work+0x98d/0x1580 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x38c/0x460 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296