INFO: task syz.4.735:8156 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.735 state:D stack:28160 pid:8156 tgid:8155 ppid:7889 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5349 [inline] __schedule+0x1665/0x5590 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7044 [inline] schedule+0x164/0x360 kernel/sched/core.c:7059 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7116 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 bdev_release+0x1a9/0x650 block/bdev.c:1144 blkdev_release+0x15/0x20 block/fops.c:705 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 get_signal+0x11eb/0x1330 kernel/signal.c:2809 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa0e159c799 RSP: 002b:00007fa0e24d3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fa0e1815fa0 RCX: 00007fa0e159c799 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fa0e1632bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa0e1816038 R14: 00007fa0e1815fa0 R15: 00007fff34932008 Showing all locks held in the system: 3 locks held by kworker/1:0/24: #0: ffff88813ff67148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x849/0x1720 kernel/workqueue.c:3257 #1: ffffc900001e7c40 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work+0x870/0x1720 kernel/workqueue.c:3258 #2: ffffffff9030c048 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 1 lock held by khungtaskd/31: #0: ffffffff8eb5e8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5e8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5e8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5593: #0: ffff8880376110a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 4 locks held by kworker/1:3/5831: #0: ffff88813ff67148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x849/0x1720 kernel/workqueue.c:3257 #1: ffffc900043b7c40 ((rfkill_op_work).work){+.+.}-{0:0}, at: process_one_work+0x870/0x1720 kernel/workqueue.c:3258 #2: ffffffff9030c048 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_epo+0x4c/0x180 net/rfkill/core.c:462 #3: ffff88805c648ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_poweroff+0x24/0xc0 net/bluetooth/hci_core.c:894 1 lock held by udevd/5845: #0: ffff8880275b1358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961 1 lock held by syz.4.735/8156: #0: ffff8880275b1358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144 1 lock held by syz-executor/8388: #0: ffffffff9030c048 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 3 locks held by syz.3.1958/11996: #0: ffffffff8f43daa8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 #1: ffff88802b47a100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #1: ffff88802b47a100 (&dev->mutex){....}-{4:4}, at: nfc_register_device+0xa1/0x380 net/nfc/core.c:1128 #2: ffffffff9030c048 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 1 lock held by syz.3.1958/12001: #0: ffffffff8f43daa8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz.6.1959/12005: #0: ffffffff8f43daa8 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x350 drivers/char/misc.c:125 1 lock held by syz.1.1964/12076: #0: ffffffff8f43daa8 (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 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0x1002/0x1060 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: cd 8e 02 e9 93 ed 02 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 73 93 29 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e807dc0 EFLAGS: 00000246 RAX: 00000000002a1dc3 RBX: ffffffff819bd79d RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8e22d498 RDI: ffffffff8c4a57e0 RBP: ffffffff8e807eb0 R08: ffff8880b843399b R09: 1ffff11017086733 R10: dffffc0000000000 R11: ffffed1017086734 R12: ffffffff9053fbf0 R13: 1ffffffff1d129d8 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124de6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556a024e8 CR3: 000000007facc000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1bd/0x500 kernel/sched/idle.c:332 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430 rest_init+0x2de/0x300 init/main.c:761 start_kernel+0x38a/0x3e0 init/main.c:1212 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147