INFO: task kworker/0:1:10 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:1 state:D stack:20296 pid:10 tgid:10 ppid:2 task_flags:0x4208060 flags:0x00[ 661.075717][ T39] task:kworker/0:1 state:D stack:20296 pid:10 tgid:10 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+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/0:4:5919 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:20808 pid:5919 tgid:5919 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+0x1e2/0x450 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+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.5.1216:10262 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.1216 state:D stack:26136 pid:10262 tgid:10261 ppid:8928 task_flags:0x400040 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 nfc_unregister_device+0x96/0x2a0 net/nfc/core.c:1167 virtual_ncidev_close+0x59/0x90 drivers/nfc/virtual_ncidev.c:172 __fput+0x45b/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 get_signal+0x11c5/0x1310 kernel/signal.c:2807 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 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: 0033:0x7fd1f60aebe9 RSP: 002b:00007fd1f430e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffea RBX: 00007fd1f62e5fa0 RCX: 00007fd1f60aebe9 RDX: 0000000000005400 RSI: 00002000000001c0 RDI: ffffffffffffff9c RBP: 00007fd1f6131e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd1f62e6038 R14: 00007fd1f62e5fa0 R15: 00007ffffe76d378 INFO: task syz.1.1246:10346 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1246 state:D stack:25496 pid:10346 tgid:10345 ppid:5837 task_flags:0x400140 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] 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 nfc_register_device+0x14a/0x320 net/nfc/core.c:1132 nci_register_device+0x87c/0x9b0 net/nfc/nci/core.c:1277 virtual_ncidev_open+0x134/0x1a0 drivers/nfc/virtual_ncidev.c:157 misc_open+0x2c2/0x340 drivers/char/misc.c:161 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x9ae/0x1350 fs/open.c:965 vfs_open+0x3b/0x350 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x2ef1/0x3840 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 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: 0033:0x7f1a5d68ebe9 RSP: 002b:00007f1a5b8f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1a5d8c5fa0 RCX: 00007f1a5d68ebe9 RDX: 0000000000000002 RSI: 0000200000000080 RDI: ffffffffffffff9c RBP: 00007f1a5d711e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000041 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1a5d8c6038 R14: 00007f1a5d8c5fa0 R15: 00007ffd0cd78298 INFO: task syz.6.1255:10377 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.1255 state:D stack:26728 pid:10377 tgid:10371 ppid:9092 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] 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 misc_open+0x51/0x340 drivers/char/misc.c:125 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x9ae/0x1350 fs/open.c:965 vfs_open+0x3b/0x350 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x2ef1/0x3840 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 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: 0033:0x7ff11402ebe9 RSP: 002b:00007ff112275038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ff114266090 RCX: 00007ff11402ebe9 RDX: 0000000000002642 RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007ff1140b1e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff114266128 R14: 00007ff114266090 R15: 00007ffd46d589b8 Showing all locks held in the system: 3 locks held by kworker/0:1/10: #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: ffffc900000f7bc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900000f7bc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8efb1938 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 1 lock held by khungtaskd/39: #0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:11/3201: 2 locks held by getty/5594: #0: ffff88823bf7a8a0 (&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/0:4/5919: #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: ffffc90004f97bc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004f97bc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8efb1938 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_sync_work+0x2e/0x200 net/rfkill/core.c:1055 #3: ffff888031bc00f0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff888031bc00f0 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline] #3: ffff888031bc00f0 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 1 lock held by syz.5.1216/10262: #0: ffff888031bc00f0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #0: ffff888031bc00f0 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165 3 locks held by syz.1.1246/10346: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 #1: ffff8880399940f0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #1: ffff8880399940f0 (&dev->mutex){....}-{4:4}, at: nfc_register_device+0xa1/0x320 net/nfc/core.c:1128 #2: ffffffff8efb1938 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x900 net/rfkill/core.c:1071 1 lock held by syz.6.1255/10377: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz.7.1283/10490: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10555: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz.8.1303/10613: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10669: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10686: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10739: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10802: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10835: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10838: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10839: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10841: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10843: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10849: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10851: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10853: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 1 lock held by syz-executor/10855: #0: ffffffff8e217618 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x340 drivers/char/misc.c:125 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400 Code: e8 6e 83 7f fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5f bd de fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07 RSP: 0018:ffffc90000167890 EFLAGS: 00000202 RAX: 1ffffffff3275600 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff993ab850 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff853edba0 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff993ab5c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881269bf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcd8115421a CR3: 000000003569c000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1984 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3288 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3311 [inline] serial8250_console_write+0x11bd/0x1b40 drivers/tty/serial/8250/8250_port.c:3396 console_emit_next_record kernel/printk/printk.c:3118 [inline] console_flush_all+0x695/0xcd0 kernel/printk/printk.c:3226 __console_flush_and_unlock+0xa4/0x240 kernel/printk/printk.c:3285 legacy_kthread_func+0x13b/0x1a0 kernel/printk/printk.c:3638 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245