INFO: task syz.2.900:8169 blocked for more than 143 seconds. Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.900 state:D stack:26280 pid:8169 tgid:8169 ppid:5814 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 hci_unregister_dev+0x360/0x500 net/bluetooth/hci_core.c:2695 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __fput+0x449/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8d6/0x2550 kernel/exit.c:953 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb03ffc1225 RSP: 002b:00007fb040df0f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007fb0401b5fa0 RCX: 00007fb03ffc1225 RDX: 00007fb040df0fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fb040010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb0401b5fa0 R15: 00007ffe0f57a168 INFO: task kworker/1:14:10426 blocked for more than 143 seconds. Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:14 state:D stack:24440 pid:10426 tgid:10426 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events rfkill_global_led_trigger_worker Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.0.3093:13506 blocked for more than 143 seconds. Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.3093 state:D stack:25400 pid:13506 tgid:13506 ppid:12937 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 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+0x449/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc4a498e969 RSP: 002b:00007ffd20e48a58 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fc4a4bb7ba0 RCX: 00007fc4a498e969 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fc4a4bb7ba0 R08: 0000000000000dc4 R09: 0000000a20e48d4f R10: 00007fc4a4bb7ac0 R11: 0000000000000246 R12: 0000000000040e1b R13: 00007fc4a4bb6080 R14: ffffffffffffffff R15: 00007ffd20e48b70 INFO: task syz.4.3101:13536 blocked for more than 144 seconds. Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.3101 state:D stack:24640 pid:13536 tgid:13528 ppid:12639 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 device_lock include/linux/device.h:922 [inline] nfc_dev_down net/nfc/core.c:143 [inline] nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 rfkill_set_block+0x1cf/0x440 net/rfkill/core.c:346 rfkill_fop_write+0x44b/0x570 net/rfkill/core.c:1301 vfs_write+0x27b/0xa90 fs/read_write.c:682 ksys_write+0x145/0x250 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f40f298e969 RSP: 002b:00007f40f3890038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f40f2bb6080 RCX: 00007f40f298e969 RDX: 0000000000000008 RSI: 0000200000000080 RDI: 0000000000000008 RBP: 00007f40f2a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f40f2bb6080 R15: 00007ffc5abf0848 INFO: task syz-executor:13717 blocked for more than 144 seconds. Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:27288 pid:13717 tgid:13717 ppid:1 task_flags:0x400040 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 hci_register_dev+0x3f5/0x890 net/bluetooth/hci_core.c:2597 __vhci_create_device drivers/bluetooth/hci_vhci.c:429 [inline] vhci_create_device+0x39c/0x6e0 drivers/bluetooth/hci_vhci.c:471 vhci_get_user drivers/bluetooth/hci_vhci.c:528 [inline] vhci_write+0x3ce/0x4a0 drivers/bluetooth/hci_vhci.c:608 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x548/0xa90 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fddbfb8d3e0 RSP: 002b:00007fffc237ca08 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fddbfb8d3e0 RDX: 0000000000000002 RSI: 00007fffc237ca1a RDI: 00000000000000ca RBP: 00007fddbfdb6738 R08: 0000000000000000 R09: 00007fddc08ed6c0 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5572: #0: ffff888034b1a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by kworker/u8:40/5985: 2 locks held by kworker/u8:44/5990: #0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 1 lock held by syz.2.900/8169: #0: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 3 locks held by kworker/1:14/10426: #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90003037c60 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003037c60 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 2 locks held by syz.0.3093/13506: #0: ffff888063879100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #0: ffff888063879100 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165 #1: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 2 locks held by syz.4.3101/13536: #0: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_fop_write+0x191/0x570 net/rfkill/core.c:1293 #1: ffff888063879100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #1: ffff888063879100 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline] #1: ffff888063879100 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 2 locks held by syz-executor/13717: #0: ffff88804ca1e918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470 #1: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 2 locks held by syz-executor/13908: #0: ffff888065857118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470 #1: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 2 locks held by syz-executor/13921: #0: ffff888028bc9118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470 #1: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 3 locks held by syz.1.3287/14011: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 #1: ffff888063545100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #1: ffff888063545100 (&dev->mutex){....}-{4:4}, at: nfc_register_device+0xa1/0x320 net/nfc/core.c:1128 #2: ffffffff8f5b6be8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 1 lock held by syz.3.3312/14068: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14071: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14073: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14075: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14078: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14079: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14081: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14083: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14089: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14092: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 1 lock held by syz-executor/14093: #0: ffffffff8e79b228 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:143 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 0 Comm: swapper/1 Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81 Code: cc cc cc cc 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 03 0b 19 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:ffffc90000197de0 EFLAGS: 000002c6 RAX: cd7619773aaf6c00 RBX: ffffffff81973e48 RCX: cd7619773aaf6c00 RDX: 0000000000000001 RSI: ffffffff8d736fa8 RDI: ffffffff8bc0fea0 RBP: ffffc90000197f20 R08: ffff8880b8932b5b R09: 1ffff1101712656b R10: dffffc0000000000 R11: ffffed101712656c R12: ffffffff8f7dae70 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110038d9b40 FS: 0000000000000000(0000) GS:ffff888126200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055597ceaf088 CR3: 000000000dd36000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147