INFO: task kworker/0:3:5855 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:20592 pid:5855 tgid:5855 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events rfkill_sync_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547 device_lock include/linux/device.h:911 [inline] nfc_dev_down net/nfc/core.c:143 [inline] nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 rfkill_set_block+0x1e5/0x450 net/rfkill/core.c:346 rfkill_sync net/rfkill/core.c:379 [inline] rfkill_sync_work+0x114/0x200 net/rfkill/core.c:1056 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/0:4:5899 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:4 state:D stack:19144 pid:5899 tgid:5899 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events rfkill_global_led_trigger_worker Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547 rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/1:6:6000 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:6 state:D stack:20872 pid:6000 tgid:6000 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events rfkill_sync_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547 rfkill_sync_work+0x2e/0x200 net/rfkill/core.c:1055 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.2.2508:11988 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2508 state:D stack:25128 pid:11988 tgid:11988 ppid:5850 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153 __flush_work+0x9b9/0xbe0 kernel/workqueue.c:4244 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4364 rfkill_unregister+0x95/0x230 net/rfkill/core.c:1139 nfc_unregister_device+0x96/0x2a0 net/nfc/core.c:1167 virtual_ncidev_close+0x59/0x90 drivers/nfc/virtual_ncidev.c:172 __fput+0x458/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4c8cc5eba9 RSP: 002b:00007ffeed1a7208 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f4c8cea7da0 RCX: 00007f4c8cc5eba9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f4c8cea7da0 R08: 0000000000000074 R09: 00000006ed1a74ff R10: 00000000003ffd68 R11: 0000000000000246 R12: 0000000000060ef5 R13: 00007f4c8cea6090 R14: ffffffffffffffff R15: 00007ffeed1a7320 INFO: task syz.1.2507:11999 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2507 state:D stack:28328 pid:11999 tgid:11990 ppid:8311 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153 __flush_work+0x9b9/0xbe0 kernel/workqueue.c:4244 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4364 rfkill_unregister+0x95/0x230 net/rfkill/core.c:1139 hci_unregister_dev+0x374/0x510 net/bluetooth/hci_core.c:2732 hci_uart_tty_close+0x1b1/0x290 drivers/bluetooth/hci_ldisc.c:557 tty_ldisc_kill+0xa3/0x1a0 drivers/tty/tty_ldisc.c:613 tty_ldisc_hangup+0x3a2/0x4b0 drivers/tty/tty_ldisc.c:729 __tty_hangup+0x418/0x690 drivers/tty/tty_io.c:621 tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0x75d/0xde0 drivers/tty/tty_io.c:2732 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdae9f1eba9 RSP: 002b:00007fdae8165038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fdaea166090 RCX: 00007fdae9f1eba9 RDX: 0000000000000000 RSI: 0000000000005437 RDI: 0000000000000003 RBP: 00007fdae9fa1e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdaea166128 R14: 00007fdaea166090 R15: 00007ffce107d5d8 INFO: task syz-executor:12003 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:27640 pid:12003 tgid:12003 ppid:1 task_flags:0x400040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547 rfkill_register+0x37/0x900 net/rfkill/core.c:1071 hci_register_dev+0x3f5/0x830 net/bluetooth/hci_core.c:2631 __vhci_create_device drivers/bluetooth/hci_vhci.c:451 [inline] vhci_create_device+0x39c/0x660 drivers/bluetooth/hci_vhci.c:479 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline] vhci_write+0x3d0/0x4a0 drivers/bluetooth/hci_vhci.c:616 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5d5/0xb40 fs/read_write.c:686 ksys_write+0x14b/0x260 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a58a2d620 RSP: 002b:00007ffe26a26f38 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2a58a2d620 RDX: 0000000000000002 RSI: 00007ffe26a26f4a RDI: 00000000000000ca RBP: 00007f2a58c767b8 R08: 0000000000000000 R09: 00007f2a597ad6c0 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:9/3527: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000d877bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000d877bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc6680 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xd1/0x230 net/rfkill/core.c:1145 2 locks held by getty/5601: #0: ffff88823bf3e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 4 locks held by kworker/0:3/5855: #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004d6fbc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004d6fbc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_sync_work+0x2e/0x200 net/rfkill/core.c:1055 #3: ffff88802840b0f0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff88802840b0f0 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline] #3: ffff88802840b0f0 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 3 locks held by kworker/0:4/5899: #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000508fbc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000508fbc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 3 locks held by kworker/1:6/6000: #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90005c1fbc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90005c1fbc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_sync_work+0x2e/0x200 net/rfkill/core.c:1055 1 lock held by syz.2.2508/11988: #0: ffff88802840b0f0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #0: ffff88802840b0f0 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165 2 locks held by syz.1.2507/11999: #0: ffff8880266a71a0 (&tty->legacy_mutex){+.+.}-{4:4}, at: __tty_hangup+0xeb/0x690 drivers/tty/tty_io.c:581 #1: ffff8880266a70a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline] #1: ffff8880266a70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock+0x6c/0xc0 drivers/tty/tty_ldisc.c:313 2 locks held by syz-executor/12003: #0: ffff88802814a988 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x660 drivers/bluetooth/hci_vhci.c:478 #1: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x900 net/rfkill/core.c:1071 2 locks held by syz-executor/12194: #0: ffff888031f5d188 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x660 drivers/bluetooth/hci_vhci.c:478 #1: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x900 net/rfkill/core.c:1071 2 locks held by syz-executor/12195: #0: ffff88803851d988 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x660 drivers/bluetooth/hci_vhci.c:478 #1: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x900 net/rfkill/core.c:1071 3 locks held by syz.3.2720/12500: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 #1: ffff888035dfe0f0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #1: ffff888035dfe0f0 (&dev->mutex){....}-{4:4}, at: nfc_register_device+0xa1/0x320 net/nfc/core.c:1128 #2: ffffffff8efb1d38 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x900 net/rfkill/core.c:1071 1 lock held by syz.6.2722/12508: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12511: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12513: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12515: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12518: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12519: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12521: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12523: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12525: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12527: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/12529: #0: ffffffff8e217918 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 13 b3 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 46 11 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8d607d80 EFLAGS: 000002c6 RAX: 4092783bdca6ca00 RBX: ffffffff81955f48 RCX: 4092783bdca6ca00 RDX: 0000000000000001 RSI: ffffffff8d03a92f RDI: ffffffff8b621300 RBP: ffffffff8d607eb8 R08: ffff8880b883341b R09: 1ffff11017106683 R10: dffffc0000000000 R11: ffffed1017106684 R12: ffffffff8f1d5f30 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1ae0620 FS: 0000000000000000(0000) GS:ffff8881268bd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffb1aaa473c CR3: 000000000d7a6000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:744 start_kernel+0x3a9/0x410 init/main.c:1097 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147