INFO: task kworker/0:13:1107 blocked for more than 143 seconds. Not tainted 5.2.0-rc4+ #46 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:13 D25760 1107 2 0x80004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 linkwatch_event+0xf/0x70 net/core/link_watch.c:231 process_one_work+0x989/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.4:2134 blocked for more than 143 seconds. Not tainted 5.2.0-rc4+ #46 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28128 2134 9080 0x00004004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 tun_detach drivers/net/tun.c:738 [inline] tun_chr_close+0x3f/0x180 drivers/net/tun.c:3451 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:185 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412f61 Code: 84 3e 02 00 00 48 8b 08 48 8b 54 24 70 48 39 d1 0f 85 41 01 00 00 0f b6 48 17 f6 c1 40 0f 85 99 00 00 00 0f b6 0d c3 a0 3b 01 <84> c9 0f 84 80 00 00 00 48 8b 48 20 31 d2 31 db eb 04 48 83 c2 08 RSP: 002b:0000000000a6fbc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412f61 RDX: 0000001b33220000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffff8100a514 R09: 00000000fc84f442 R10: 0000000000a6fca0 R11: 0000000000000293 R12: 0000000000760530 R13: 00000000000cf4a2 R14: 00000000000cf4cf R15: 000000000075bfcc INFO: task syz-executor.5:2145 blocked for more than 143 seconds. Not tainted 5.2.0-rc4+ #46 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27040 2145 9084 0x00004004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 exp_funnel_lock kernel/rcu/tree_exp.h:309 [inline] synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:790 synchronize_net+0x3b/0x60 net/core/dev.c:9241 rollback_registered_many+0xb2c/0xfc0 net/core/dev.c:8209 rollback_registered+0x109/0x1d0 net/core/dev.c:8220 unregister_netdevice_queue net/core/dev.c:9267 [inline] unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9260 unregister_netdevice include/linux/netdevice.h:2631 [inline] __tun_detach+0xd8a/0x1040 drivers/net/tun.c:724 tun_detach drivers/net/tun.c:741 [inline] tun_chr_close+0xe0/0x180 drivers/net/tun.c:3451 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:185 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412f61 Code: 84 3e 02 00 00 48 8b 08 48 8b 54 24 70 48 39 d1 0f 85 41 01 00 00 0f b6 48 17 f6 c1 40 0f 85 99 00 00 00 0f b6 0d c3 a0 3b 01 <84> c9 0f 84 80 00 00 00 48 8b 48 20 31 d2 31 db eb 04 48 83 c2 08 RSP: 002b:0000000000a6fbc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412f61 RDX: 0000001b33620000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffff8132af1a R09: 00000000fc84f442 R10: 0000000000a6fca0 R11: 0000000000000293 R12: 0000000000760530 R13: 00000000000cf4d3 R14: 00000000000cf500 R15: 000000000075bf2c INFO: task syz-executor.1:2155 blocked for more than 144 seconds. Not tainted 5.2.0-rc4+ #46 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28384 2155 9070 0x00000004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 __tun_chr_ioctl+0x206/0x3ea0 drivers/net/tun.c:3067 tun_chr_ioctl+0x2b/0x40 drivers/net/tun.c:3357 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: ac 00 00 00 48 83 ec 28 48 89 6c 24 20 48 8d 6c 24 20 48 8b 42 08 48 89 44 24 08 84 00 48 89 04 24 e8 eb 61 fb ff 48 8b 44 24 <08> 8b 48 10 85 c9 76 18 ff c9 89 48 10 48 89 04 24 e8 71 63 fb ff RSP: 002b:00007f16394d0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279 RDX: 0000000020000000 RSI: 00000000400454ca RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f16394d16d4 R13: 00000000004c3c98 R14: 00000000004d7878 R15: 00000000ffffffff INFO: task syz-executor.1:2156 blocked for more than 144 seconds. Not tainted 5.2.0-rc4+ #46 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29488 2156 9070 0x00000004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 __tun_chr_ioctl+0x3cd/0x3ea0 drivers/net/tun.c:3067 tun_chr_ioctl+0x2b/0x40 drivers/net/tun.c:3357 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: ac 00 00 00 48 83 ec 28 48 89 6c 24 20 48 8d 6c 24 20 48 8b 42 08 48 89 44 24 08 84 00 48 89 04 24 e8 eb 61 fb ff 48 8b 44 24 <08> 8b 48 10 85 c9 76 18 ff c9 89 48 10 48 89 04 24 e8 71 63 fb ff RSP: 002b:00007f16394afc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279 RDX: 0000000020000080 RSI: 00000000400454dc RDI: 0000000000000003 RBP: 000000000075bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f16394b06d4 R13: 00000000004c3d96 R14: 00000000004d79b0 R15: 00000000ffffffff INFO: task syz-executor.1:2158 blocked for more than 144 seconds. Not tainted 5.2.0-rc4+ #46 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29680 2158 9070 0x00000004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 dev_ioctl+0x1a4/0xc60 net/core/dev_ioctl.c:488 sock_do_ioctl+0x1b7/0x2f0 net/socket.c:1066 sock_ioctl+0x3ed/0x780 net/socket.c:1194 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: ac 00 00 00 48 83 ec 28 48 89 6c 24 20 48 8d 6c 24 20 48 8b 42 08 48 89 44 24 08 84 00 48 89 04 24 e8 eb 61 fb ff 48 8b 44 24 <08> 8b 48 10 85 c9 76 18 ff c9 89 48 10 48 89 04 24 e8 71 63 fb ff RSP: 002b:00007f163948ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459279 RDX: 0000000020000500 RSI: 0000000000008914 RDI: 0000000000000004 RBP: 000000000075c060 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f163948f6d4 R13: 00000000004cc708 R14: 00000000004d5c58 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 00000000e7cdfe84 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5149 1 lock held by rsyslogd/8939: #0: 00000000db82a7fd (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9029: #0: 00000000b80f9fb2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e3a0c5f0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9030: #0: 00000000880051d8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f426158d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9031: #0: 00000000fd215853 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e9d2ae1b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9032: #0: 0000000089fbc161 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000018bd26ce (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9033: #0: 0000000048047934 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a679eb79 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9034: #0: 0000000030df6f0b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000161ca816 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9035: #0: 00000000082f0c0a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000082e6b95b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 3 locks held by kworker/1:2/9071: #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:221 [inline] #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 000000005082b6bf ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 00000000f5fac457 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/u4:14/29011: #0: 000000005ac26034 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:10083 [inline] #0: 000000005ac26034 (&rq->lock){-.-.}, at: pick_next_task_fair+0x120e/0x1990 kernel/sched/fair.c:7090 #1: 00000000e7cdfe84 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:6087 #2: 000000003b759b8c (&base->lock){-.-.}, at: lock_timer_base+0x56/0x1b0 kernel/time/timer.c:932 3 locks held by syz-executor.4/29641: #0: 00000000c6f43b3e (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 00000000c6f43b3e (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:600 #1: 00000000b4b02bf1 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x390 net/core/dev.c:1713 #2: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 2 locks held by syz-executor.4/29657: #0: 00000000a297dd9d (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 00000000a297dd9d (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:600 #1: 00000000b4b02bf1 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x390 net/core/dev.c:1713 2 locks held by syz-executor.5/29667: #0: 00000000a025ff6b (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 00000000a025ff6b (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:600 #1: 00000000b4b02bf1 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x390 net/core/dev.c:1713 2 locks held by syz-executor.4/29677: #0: 0000000056d9a0ce (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 0000000056d9a0ce (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:600 #1: 00000000b4b02bf1 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x390 net/core/dev.c:1713 3 locks held by kworker/0:13/1107: #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:221 [inline] #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 0000000030076be6 ((wq_completion)events){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 000000000bdf1237 ((linkwatch_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.4/2134: #0: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.5/2145: #0: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.1/2155: #0: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.1/2156: #0: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.1/2158: #0: 00000000f4919653 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1042 Comm: khungtaskd Not tainted 5.2.0-rc4+ #46 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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:289 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60