INFO: task kworker/0:16:8104 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:16 state:D stack:24328 pid:8104 tgid:8104 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events rfkill_sync_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 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+0x1d2/0x440 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+0xae1/0x17b0 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/0:18:8106 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:18 state:D stack:24152 pid:8106 tgid:8106 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+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 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.2.2649:15132 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2649 state:D stack:26920 pid:15132 tgid:15132 ppid:5874 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 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+0x9b9/0xbc0 kernel/workqueue.c:4244 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4364 rfkill_unregister+0x92/0x220 net/rfkill/core.c:1139 nfc_unregister_device+0x96/0x2a0 net/nfc/core.c:1167 virtual_ncidev_close+0x56/0x90 drivers/nfc/virtual_ncidev.c:172 __fput+0x44c/0xa70 fs/file_table.c:468 task_work_run+0x1d1/0x260 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: 0033:0x7f383ad8eec9 RSP: 002b:00007ffc3cd29aa8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000003c62a RCX: 00007f383ad8eec9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f383afe7da0 R08: 0000000000000001 R09: 0000001e3cd29d9f R10: 0000001b32620000 R11: 0000000000000246 R12: 00007f383afe5fac R13: 00007f383afe5fa0 R14: ffffffffffffffff R15: 00007ffc3cd29bc0 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: #0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636 1 lock held by khungtaskd/31: #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by klogd/5227: #0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636 2 locks held by getty/5627: #0: ffff88814ced30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/0:16/8104: #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9001ce17bc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9001ce17bc0 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f813fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_sync_work+0x2e/0x200 net/rfkill/core.c:1055 #3: ffff888055fd6100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff888055fd6100 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline] #3: ffff888055fd6100 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 3 locks held by kworker/0:18/8106: #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9001ce97bc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9001ce97bc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f813fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 1 lock held by syz.2.2649/15132: #0: ffff888055fd6100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #0: ffff888055fd6100 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165 3 locks held by syz.1.2707/15307: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 #1: ffff88807e21c100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #1: ffff88807e21c100 (&dev->mutex){....}-{4:4}, at: nfc_register_device+0xa1/0x320 net/nfc/core.c:1128 #2: ffffffff8f813fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 1 lock held by syz.1.2707/15312: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15331: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz.4.2716/15340: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz.0.2719/15355: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz.3.2732/15402: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15409: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15410: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15411: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15413: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15415: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15419: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15420: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15421: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/15423: #0: ffffffff8e9c2708 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(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: 7764 Comm: kworker/u8:47 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:19 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:151 [inline] RIP: 0010:lock_acquire+0x146/0x360 kernel/locking/lockdep.c:5871 Code: e0 02 00 00 48 83 c4 28 48 c7 c7 22 9b ba 8d e8 f0 32 dd 09 b8 ff ff ff ff 65 0f c1 05 93 c0 03 11 83 f8 01 0f 85 c9 00 00 00 <48> c7 44 24 30 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 RSP: 0018:ffffc9001c6878d0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000000 RCX: fa0f286de83f1100 RDX: 0000000000000000 RSI: ffffffff8dba9b22 RDI: ffffffff8be33f80 RBP: ffffffff8b486047 R08: 0000000000000000 R09: ffffffff8b486047 R10: dffffc0000000000 R11: fffffbfff1f47507 R12: 0000000000000000 R13: ffff8880294c1b58 R14: 0000000000000001 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888125c12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffee1a023e8 CR3: 000000000df36000 CR4: 00000000003526f0 Call Trace: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xe7/0x3b0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x369/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 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