INFO: task syz-executor:5818 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21248 pid:5818 tgid:5818 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:240 __wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit include/linux/wait_bit.h:77 [inline] gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1269 gfs2_glock_nq_init fs/gfs2/glock.h:253 [inline] __gfs2_lookup+0x134/0x2a0 fs/gfs2/inode.c:999 __lookup_slow+0x2b7/0x410 fs/namei.c:1916 lookup_slow+0x53/0x70 fs/namei.c:1933 walk_component fs/namei.c:2279 [inline] lookup_last fs/namei.c:2780 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2804 filename_lookup+0x256/0x5d0 fs/namei.c:2833 user_path_at+0x40/0x160 fs/namei.c:3612 ksys_umount fs/namespace.c:2052 [inline] __do_sys_umount fs/namespace.c:2060 [inline] __se_sys_umount fs/namespace.c:2058 [inline] __x64_sys_umount+0xf6/0x170 fs/namespace.c:2058 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7ac8f9c117 RSP: 002b:00007ffc439b0f98 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f7ac900471f RCX: 00007f7ac8f9c117 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc439b1050 RBP: 00007ffc439b1050 R08: 0000000000000000 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc439b2140 R13: 00007f7ac900471f R14: 000000000001aa61 R15: 00007ffc439b4300 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e760320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:6/1111: #0: ffff88801df5e948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc90003aefc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 2 locks held by getty/5576: #0: ffff8880319fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5818: #0: ffff88805a2107e8 (&type->i_mutex_dir_key#11){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff88805a2107e8 (&type->i_mutex_dir_key#11){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932 1 lock held by syz.0.1143/9349: ============================================= 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 01/24/2026 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:161 [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:347 [inline] watchdog+0x103d/0x1090 kernel/hung_task.c:516 kthread+0x388/0x470 kernel/kthread.c:467 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: 5832 Comm: kworker/u9:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: hci5 hci_ncmd_timeout RIP: 0010:__bfs kernel/locking/lockdep.c:1815 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline] RIP: 0010:__lock_acquire+0x197b/0x2cf0 kernel/locking/lockdep.c:5237 Code: 14 25 ff 0f 00 00 39 05 8f 8f 81 12 73 06 89 05 87 8f 81 12 48 8b 02 48 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 18 fe ff ff 48 89 fb 48 c7 c7 d0 e4 62 RSP: 0018:ffffc900045ef308 EFLAGS: 00000002 RAX: ffffffff96c423a8 RBX: 00000000000003cd RCX: 000000000000000b RDX: ffffffff96a92b08 RSI: ffff88807ae266a0 RDI: 00000000000003cd RBP: e0c31a4067b92586 R08: ffffc900045ef2d0 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff81a1fa40 R12: ffffffff96a8e6c8 R13: ffffffff93c5d890 R14: ffff88807ae25ac0 R15: 000000000000000a FS: 0000000000000000(0000) GS:ffff88812546a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000078ef2000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline] serial8250_console_write+0x150/0x1ba0 drivers/tty/serial/8250/8250_port.c:3301 console_emit_next_record kernel/printk/printk.c:3131 [inline] console_flush_one_record kernel/printk/printk.c:3217 [inline] console_flush_all+0x718/0xb20 kernel/printk/printk.c:3291 __console_flush_and_unlock kernel/printk/printk.c:3321 [inline] console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3361 vprintk_emit+0x485/0x560 kernel/printk/printk.c:2428 _printk+0xdd/0x130 kernel/printk/printk.c:2453 bt_err+0x121/0x180 net/bluetooth/lib.c:296 hci_ncmd_timeout+0x68/0xd0 net/bluetooth/hci_core.c:1490 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 14 25 adc $0x25,%al 2: ff 0f decl (%rdi) 4: 00 00 add %al,(%rax) 6: 39 05 8f 8f 81 12 cmp %eax,0x12818f8f(%rip) # 0x12818f9b c: 73 06 jae 0x14 e: 89 05 87 8f 81 12 mov %eax,0x12818f87(%rip) # 0x12818f9b 14: 48 8b 02 mov (%rdx),%rax 17: 48 89 df mov %rbx,%rdi 1a: 4c 39 e8 cmp %r13,%rax 1d: 0f 84 2c fe ff ff je 0xfffffe4f 23: 4c 89 60 30 mov %r12,0x30(%rax) 27: 48 8b 00 mov (%rax),%rax * 2a: 4c 39 e8 cmp %r13,%rax <-- trapping instruction 2d: 75 f4 jne 0x23 2f: 48 89 df mov %rbx,%rdi 32: e9 18 fe ff ff jmp 0xfffffe4f 37: 48 89 fb mov %rdi,%rbx 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: c7 (bad) 3d: d0 e4 shl $1,%ah 3f: 62 .byte 0x62