INFO: task kworker/1:0:20 blocked for more than 143 seconds. Not tainted 6.1.0-rc3-syzkaller-00058-gdd65a243a915 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:21544 pid:20 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5191 [inline] __schedule+0x979/0x2770 kernel/sched/core.c:6503 schedule+0xda/0x1b0 kernel/sched/core.c:6579 rwsem_down_write_slowpath+0x5fc/0x12d0 kernel/locking/rwsem.c:1190 __down_write_common kernel/locking/rwsem.c:1305 [inline] __down_write_common kernel/locking/rwsem.c:1302 [inline] __down_write kernel/locking/rwsem.c:1314 [inline] down_write+0x1e4/0x220 kernel/locking/rwsem.c:1563 usb_register_dev drivers/usb/core/file.c:187 [inline] usb_register_dev+0x198/0x7e0 drivers/usb/core/file.c:156 usblp_probe+0x1185/0x1530 drivers/usb/class/usblp.c:1208 usb_probe_interface+0x30b/0x7f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:560 [inline] really_probe+0x249/0xb90 drivers/base/dd.c:639 __driver_probe_device+0x1df/0x4d0 drivers/base/dd.c:778 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:808 __device_attach_driver+0x1d0/0x2e0 drivers/base/dd.c:936 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 __device_attach+0x1e4/0x530 drivers/base/dd.c:1008 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487 device_add+0xbd5/0x1e90 drivers/base/core.c:3517 usb_set_configuration+0x1019/0x1900 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238 usb_probe_device+0xd4/0x2c0 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:560 [inline] really_probe+0x249/0xb90 drivers/base/dd.c:639 __driver_probe_device+0x1df/0x4d0 drivers/base/dd.c:778 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:808 __device_attach_driver+0x1d0/0x2e0 drivers/base/dd.c:936 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 __device_attach+0x1e4/0x530 drivers/base/dd.c:1008 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487 device_add+0xbd5/0x1e90 drivers/base/core.c:3517 usb_new_device.cold+0x685/0x10ad drivers/usb/core/hub.c:2573 hub_port_connect drivers/usb/core/hub.c:5405 [inline] hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] port_event drivers/usb/core/hub.c:5709 [inline] hub_event+0x2d58/0x4810 drivers/usb/core/hub.c:5791 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2ea/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 INFO: task syz-executor.3:22984 blocked for more than 143 seconds. Not tainted 6.1.0-rc3-syzkaller-00058-gdd65a243a915 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:29000 pid:22984 ppid:1296 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5191 [inline] __schedule+0x979/0x2770 kernel/sched/core.c:6503 schedule+0xda/0x1b0 kernel/sched/core.c:6579 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa44/0x1350 kernel/locking/mutex.c:747 sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 usb_open+0x204/0x2e0 drivers/usb/core/file.c:48 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x6c7/0x12a0 fs/open.c:882 do_open fs/namei.c:3557 [inline] path_openat+0x1bf6/0x2860 fs/namei.c:3713 do_filp_open+0x1b6/0x400 fs/namei.c:3740 do_sys_openat2+0x16d/0x4c0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f4e226496e4 RSP: 002b:00007f4e21a0aca0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f4e227b7f80 RCX: 00007f4e226496e4 RDX: 0000000000000002 RSI: 00007f4e21a0ad40 RDI: 00000000ffffff9c RBP: 00007f4e21a0ad40 R08: 0000000000000000 R09: 000000000000000f R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 00007fffc3c928ff R14: 00007f4e21a0b300 R15: 0000000000022000 Showing all locks held in the system: 6 locks held by kworker/0:0/7: #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000007fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88810f689190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #2: ffff88810f689190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1bc/0x4810 drivers/usb/core/hub.c:5737 #3: ffff88810e8e54f0 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3145 [inline] #3: ffff88810e8e54f0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5301 [inline] #3: ffff88810e8e54f0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #3: ffff88810e8e54f0 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #3: ffff88810e8e54f0 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2778/0x4810 drivers/usb/core/hub.c:5791 #4: ffff88810f060d68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5302 [inline] #4: ffff88810f060d68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5549 [inline] #4: ffff88810f060d68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5709 [inline] #4: ffff88810f060d68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x27ad/0x4810 drivers/usb/core/hub.c:5791 #5: ffff8881f6837d18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:537 [inline] #5: ffff8881f6837d18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1354 [inline] #5: ffff8881f6837d18 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1644 [inline] #5: ffff8881f6837d18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x236/0x2770 kernel/sched/core.c:6420 1 lock held by rcu_tasks_kthre/11: #0: ffffffff87a95f50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 6 locks held by kworker/1:0/20: #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000015fda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88810f7e2190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #2: ffff88810f7e2190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1bc/0x4810 drivers/usb/core/hub.c:5737 #3: ffff8881370ac190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #3: ffff8881370ac190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x530 drivers/base/dd.c:983 #4: ffff888110d25118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #4: ffff888110d25118 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x530 drivers/base/dd.c:983 #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline] #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x198/0x7e0 drivers/usb/core/file.c:156 1 lock held by khungtaskd/25: #0: ffffffff87a96aa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6494 6 locks held by kworker/0:2/72: #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc900004f7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88810f7fa190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #2: ffff88810f7fa190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1bc/0x4810 drivers/usb/core/hub.c:5737 #3: ffff88810df25190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #3: ffff88810df25190 (&dev->mutex){....}-{3:3}, at: usb_disconnect.cold+0x43/0x6ed drivers/usb/core/hub.c:2226 #4: ffff888109a9b118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #4: ffff888109a9b118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1073 [inline] #4: ffff888109a9b118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa0/0x700 drivers/base/dd.c:1272 #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_deregister_dev+0xa5/0x320 drivers/usb/core/file.c:239 2 locks held by getty/1223: #0: ffff88810020b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900000452f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef0/0x13e0 drivers/tty/n_tty.c:2177 6 locks held by kworker/1:3/14483: #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000d867da8 ( (work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88810f792190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #2: ffff88810f792190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1bc/0x4810 drivers/usb/core/hub.c:5737 #3: ffff88810f14a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #3: ffff88810f14a190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x530 drivers/base/dd.c:983 #4: ffff88810f14c118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #4: ffff88810f14c118 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x530 drivers/base/dd.c:983 #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline] #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x198/0x7e0 drivers/usb/core/file.c:156 6 locks held by kworker/0:3/18052: #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888109c84d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc9000d4cfda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88810f77a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] (&dev->mutex){....}-{3:3}, at: hub_event+0x1bc/0x4810 drivers/usb/core/hub.c:5737 #3: ffff88811d20f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #3: ffff88811d20f190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x530 drivers/base/dd.c:983 #4: ffff888112cf8118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline] #4: ffff888112cf8118 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x530 drivers/base/dd.c:983 #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline] #5: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x198/0x7e0 drivers/usb/core/file.c:156 2 locks held by syz-executor.3/22984: #0: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39 #1: ffff888113fbd0d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 3 locks held by udevd/22982: #0: ffff88811c4b8088 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:236 [inline] #0: ffff88811c4b8088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x189/0x7a0 fs/kernfs/file.c:276 #1: ffff8881179cc0f0 (kn->active#27){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:237 [inline] #1: ffff8881179cc0f0 (kn->active#27){++++}-{0:0}, at: kernfs_fop_read_iter+0x1ac/0x7a0 fs/kernfs/file.c:276 #2: ffff8881370ac190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:840 [inline] #2: ffff8881370ac190 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:874 2 locks held by syz-executor.2/22997: #0: ffffffff88422330 (minor_rwsem){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39 #1: ffff888113fbd0d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2396 3 locks held by udevd/24485: #0: ffff88811404d888 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:236 [inline] #0: ffff88811404d888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x189/0x7a0 fs/kernfs/file.c:276 #1: ffff88810921da00 (kn->active#27){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:237 [inline] #1: ffff88810921da00 (kn->active#27){++++}-{0:0}, at: kernfs_fop_read_iter+0x1ac/0x7a0 fs/kernfs/file.c:276 #2: ffff88811d20f190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:840 [inline] #2: ffff88811d20f190 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:874 3 locks held by udevd/24486: #0: ffff88810f6f4888 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:236 [inline] #0: ffff88810f6f4888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x189/0x7a0 fs/kernfs/file.c:276 #1: ffff88811759bcb8 (kn->active#27){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:237 [inline] #1: ffff88811759bcb8 (kn->active#27){++++}-{0:0}, at: kernfs_fop_read_iter+0x1ac/0x7a0 fs/kernfs/file.c:276 #2: ffff88810f14a190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:840 [inline] #2: ffff88810f14a190 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:874 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 25 Comm: khungtaskd Not tainted 6.1.0-rc3-syzkaller-00058-gdd65a243a915 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x24/0x18a lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x32f/0x3c0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xc71/0xfc0 kernel/hung_task.c:377 kthread+0x2ea/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 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:112 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x1fd/0x2a0 drivers/acpi/processor_idle.c:572