INFO: task kworker/0:2:42 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:21248 pid:42 tgid:42 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d8/0x200 kernel/locking/rwsem.c:1580 usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134 usbtmc_probe+0xdbf/0x1b10 drivers/usb/class/usbtmc.c:2461 usb_probe_interface+0x309/0x9d0 drivers/usb/core/driver.c:399 call_driver_probe drivers/base/dd.c:578 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:457 __device_attach+0x1e8/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:532 device_add+0x114b/0x1a70 drivers/base/core.c:3682 usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:254 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294 call_driver_probe drivers/base/dd.c:578 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:457 __device_attach+0x1e8/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:532 device_add+0x114b/0x1a70 drivers/base/core.c:3682 usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2651 hub_port_connect drivers/usb/core/hub.c:5521 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x2e58/0x4f40 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.1.3963:21072 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.3963 state:D stack:28320 pid:21072 tgid:21071 ppid:17524 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 usblp_open+0x5c/0x450 drivers/usb/class/usblp.c:417 usb_open+0x213/0x2f0 drivers/usb/core/file.c:47 chrdev_open+0x26d/0x6f0 fs/char_dev.c:414 do_dentry_open+0x957/0x1490 fs/open.c:959 vfs_open+0x82/0x3f0 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2141/0x2d20 fs/namei.c:3886 do_filp_open+0x1dc/0x430 fs/namei.c:3913 do_sys_openat2+0x17a/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f12f22dc890 RSP: 002b:00007f12f0f50b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f12f22dc890 RDX: 0000000000000002 RSI: 00007f12f0f50c10 RDI: 00000000ffffff9c RBP: 00007f12f0f50c10 R08: 0000000000000000 R09: 00007f12f0f50987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f12f2495f80 R15: 00007ffecc7f06d8 INFO: task syz.1.3963:21081 blocked for more than 144 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.3963 state:D stack:28992 pid:21081 tgid:21071 ppid:17524 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 usblp_open+0x5c/0x450 drivers/usb/class/usblp.c:417 usb_open+0x213/0x2f0 drivers/usb/core/file.c:47 chrdev_open+0x26d/0x6f0 fs/char_dev.c:414 do_dentry_open+0x957/0x1490 fs/open.c:959 vfs_open+0x82/0x3f0 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2141/0x2d20 fs/namei.c:3886 do_filp_open+0x1dc/0x430 fs/namei.c:3913 do_sys_openat2+0x17a/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f12f22dc890 RSP: 002b:00007f12f0f2fb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f12f22dc890 RDX: 0000000000000002 RSI: 00007f12f0f2fc10 RDI: 00000000ffffff9c RBP: 00007f12f0f2fc10 R08: 0000000000000000 R09: 00007f12f0f2f987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f12f2496058 R15: 00007ffecc7f06d8 INFO: task syz.4.3967:21092 blocked for more than 144 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.3967 state:D stack:28960 pid:21092 tgid:21086 ppid:16403 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 usblp_open+0x5c/0x450 drivers/usb/class/usblp.c:417 usb_open+0x213/0x2f0 drivers/usb/core/file.c:47 chrdev_open+0x26d/0x6f0 fs/char_dev.c:414 do_dentry_open+0x957/0x1490 fs/open.c:959 vfs_open+0x82/0x3f0 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2141/0x2d20 fs/namei.c:3886 do_filp_open+0x1dc/0x430 fs/namei.c:3913 do_sys_openat2+0x17a/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6640e9c890 RSP: 002b:00007f663faefb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f6640e9c890 RDX: 0000000000000002 RSI: 00007f663faefc10 RDI: 00000000ffffff9c RBP: 00007f663faefc10 R08: 0000000000000000 R09: 00007f663faef987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6641056058 R15: 00007ffd8d32c598 INFO: task syz.3.3976:21296 blocked for more than 145 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.3976 state:D stack:28992 pid:21296 tgid:21224 ppid:15266 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x124/0x330 kernel/locking/rwsem.c:1528 usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 chrdev_open+0x26d/0x6f0 fs/char_dev.c:414 do_dentry_open+0x957/0x1490 fs/open.c:959 vfs_open+0x82/0x3f0 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2141/0x2d20 fs/namei.c:3886 do_filp_open+0x1dc/0x430 fs/namei.c:3913 do_sys_openat2+0x17a/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa21de4c890 RSP: 002b:00007fa21ca84b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fa21de4c890 RDX: 0000000000000002 RSI: 00007fa21ca84c10 RDI: 00000000ffffff9c RBP: 00007fa21ca84c10 R08: 0000000000000000 R09: 00007fa21ca84987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fa21e006130 R15: 00007ffd5fe6ac38 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 6 locks held by kworker/0:2/42: #0: ffff888105ebed48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc900004d7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff8881097d5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff8881097d5190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888132ea1190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff888132ea1190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1004 #4: ffff88811ce4e160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88811ce4e160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1004 #5: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134 2 locks held by getty/2609: #0: ffff88810f3e30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 5 locks held by kworker/0:0/19284: #0: ffff888105ebed48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc900059b7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff888109337190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff888109337190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88810db08190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff88810db08190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff888104a93160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff888104a93160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff888104a93160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 1 lock held by syz.0.3957/21061: #0: ffffffff89a693e8 (usblp_mutex){+.+.}-{3:3}, at: usblp_release+0x7f/0x310 drivers/usb/class/usblp.c:480 2 locks held by syz.1.3963/21072: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 #1: ffffffff89a693e8 (usblp_mutex){+.+.}-{3:3}, at: usblp_open+0x5c/0x450 drivers/usb/class/usblp.c:417 2 locks held by syz.1.3963/21081: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 #1: ffffffff89a693e8 (usblp_mutex){+.+.}-{3:3}, at: usblp_open+0x5c/0x450 drivers/usb/class/usblp.c:417 2 locks held by syz.4.3967/21092: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 #1: ffffffff89a693e8 (usblp_mutex){+.+.}-{3:3}, at: usblp_open+0x5c/0x450 drivers/usb/class/usblp.c:417 5 locks held by kworker/u8:1/21193: #0: ffff888100abb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc90010d87d80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffffffff8a161d50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xbb0 net/core/net_namespace.c:594 #3: ffffffff8a1776e8 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x503/0xbb0 net/core/net_namespace.c:630 #4: ffffffff88ec6df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:296 1 lock held by syz.3.3976/21296: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.4.3978/22876: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.4.3978/22881: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.2.3997/22900: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.1.4000/22975: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.1.4000/22984: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.3.4018/23133: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.2.4016/24720: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.1.4020/24804: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.3.4024/24982: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.4.4053/25049: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.4.4053/25055: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.4.4053/25057: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.0.4060/25796: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.2.4048/26447: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.1.4062/26617: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.3.4070/27154: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.4.4077/27531: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 1 lock held by syz.0.4081/28008: #0: ffffffff899b0110 (minor_rwsem){++++}-{3:3}, at: usb_open+0x27/0x2f0 drivers/usb/core/file.c:38 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111