INFO: task kworker/1:4:5906 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:23416 pid:5906 tgid:5906 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events rfkill_global_led_trigger_worker Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INFO: task syz.1.5109:23006 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.5109 state:D stack:25432 pid:23006 tgid:23006 ppid:16547 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 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+0x1d4/0x260 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1232b8f749 RSP: 002b:00007ffc18d0acd8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f1232de7da0 RCX: 00007f1232b8f749 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f1232de7da0 R08: 000000000000014c R09: 0000001318d0afcf R10: 00007f1232de7cb0 R11: 0000000000000246 R12: 000000000007d1c0 R13: 00007f1232de6090 R14: ffffffffffffffff R15: 00007ffc18d0adf0 INFO: task syz.1.5109:23007 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.5109 state:D stack:24096 pid:23007 tgid:23006 ppid:16547 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 device_lock include/linux/device.h:914 [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_fop_write+0x44b/0x570 net/rfkill/core.c:1301 vfs_write+0x27e/0xb30 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1232b8f749 RSP: 002b:00007f1233943038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1232de5fa0 RCX: 00007f1232b8f749 RDX: 0000000000000008 RSI: 0000200000000080 RDI: 0000000000000003 RBP: 00007f1232c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1232de6038 R14: 00007f1232de5fa0 R15: 00007ffc18d0ab78 INFO: task syz.2.5166:23211 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.5166 state:D stack:23128 pid:23211 tgid:23208 ppid:16861 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 rfkill_fop_open+0x12d/0x820 net/rfkill/core.c:1178 misc_open+0x2d5/0x350 drivers/char/misc.c:163 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x7ce/0x1420 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4628 [inline] path_openat+0x340e/0x3dd0 fs/namei.c:4787 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f771218f749 RSP: 002b:00007f7712f7a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f77123e5fa0 RCX: 00007f771218f749 RDX: 0000000000000801 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f7712213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f77123e6038 R14: 00007f77123e5fa0 R15: 00007ffcb2fcb1b8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5582: #0: ffff8880301f60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/1:4/5906: #0: ffff88801a055948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801a055948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000b547b80 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000b547b80 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8f5e15e8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 2 locks held by syz.1.5109/23006: #0: ffff888077bec100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #0: ffff888077bec100 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165 #1: ffffffff8f5e15e8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 2 locks held by syz.1.5109/23007: #0: ffffffff8f5e15e8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_fop_write+0x191/0x570 net/rfkill/core.c:1293 #1: ffff888077bec100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #1: ffff888077bec100 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline] #1: ffff888077bec100 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 2 locks held by syz.2.5166/23211: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 #1: ffffffff8f5e15e8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_fop_open+0x12d/0x820 net/rfkill/core.c:1178 1 lock held by syz.3.5175/23243: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz.3.5175/23252: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz.4.5181/23264: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 3 locks held by syz.0.5185/23276: #0: ffffffff8f35d1b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8f35cfc8 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f35cfc8 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f35cfc8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209 #2: ffffffff8f5e15e8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 1 lock held by syz-executor/23279: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23281: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23285: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23286: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23287: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23289: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23291: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23295: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23296: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23297: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23299: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23301: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23305: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23306: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz-executor/23307: #0: ffffffff8e78ce48 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 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 10/25/2025 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:332 [inline] watchdog+0xf3c/0xf80 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:222 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:233 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:647 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1229 [inline] RIP: 0010:trace_netif_rx_exit+0x5d/0x1d0 include/trace/events/net.h:319 Code: f8 41 89 de c1 eb 06 48 8d 3c dd 70 5a 80 8f be 08 00 00 00 e8 b4 69 fd f8 31 f6 4c 0f a3 35 3a 93 56 06 0f 92 c3 40 0f 92 c6 02 00 00 00 e8 19 86 97 f8 84 db 74 10 e8 c0 7d 7d f8 84 c0 74 RSP: 0018:ffffc900001174c0 EFLAGS: 00000247 RAX: ffffffff8929c701 RBX: 0000000000000001 RCX: ffffffff8929c72c RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8f805a70 RBP: 0000000000000200 R08: ffffffff8f805a77 R09: 1ffffffff1f00b4e R10: dffffc0000000000 R11: fffffbfff1f00b4f R12: ffff8880541b52c3 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804cd373c0 FS: 0000000000000000(0000) GS:ffff8881260b1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000560a515f1000 CR3: 000000000dd3a000 CR4: 00000000003526f0 Call Trace: __netif_rx+0x81/0xc0 net/core/dev.c:5668 veth_forward_skb drivers/net/veth.c:321 [inline] veth_xmit+0x57a/0xd50 drivers/net/veth.c:375 __netdev_start_xmit include/linux/netdevice.h:5272 [inline] netdev_start_xmit include/linux/netdevice.h:5281 [inline] xmit_one net/core/dev.c:3853 [inline] dev_hard_start_xmit+0x2cd/0x800 net/core/dev.c:3869 __dev_queue_xmit+0x1493/0x3140 net/core/dev.c:4817 dev_queue_xmit include/linux/netdevice.h:3381 [inline] batadv_send_skb_packet+0x418/0x690 net/batman-adv/send.c:100 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:391 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x62f/0x7e0 net/batman-adv/bat_iv_ogm.c:1697 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246