INFO: task iou-wrk-5843:5844 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:iou-wrk-5843    state:D stack:25304 pid:5844  tgid:5842  ppid:5618   task_flags:0x404150 flags:0x00080006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x125c/0x6730 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0xdd/0x2c0 kernel/sched/core.c:7326
 do_uevent+0x427/0x530 fs/dlm/lockspace.c:206
 new_lockspace fs/dlm/lockspace.c:583 [inline]
 __dlm_new_lockspace+0x1698/0x1fa0 fs/dlm/lockspace.c:638
 dlm_new_user_lockspace+0x60/0x90 fs/dlm/lockspace.c:671
 device_create_lockspace fs/dlm/user.c:414 [inline]
 device_write+0x930/0x1c90 fs/dlm/user.c:606
 loop_rw_iter+0x305/0x6a0 io_uring/rw.c:735
 io_write+0x111d/0x1670 io_uring/rw.c:1184
 __io_issue_sqe+0xe8/0x7a0 io_uring/io_uring.c:1395
 io_issue_sqe+0x88/0x1540 io_uring/io_uring.c:1418
 io_wq_submit_work+0x3b6/0xf70 io_uring/io_uring.c:1534
 io_worker_handle_work+0x5aa/0x1570 io_uring/io-wq.c:652
 io_wq_worker+0x33e/0xe60 io_uring/io-wq.c:706
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8ebe8200 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
1 lock held by klogd/4964:
 #0: ffff8880b843b520 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:667
2 locks held by getty/5365:
 #0: ffff888036c590a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
1 lock held by iou-wrk-5843/5844:
 #0: ffffffff9b7cf4c0 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xb8/0x1fa0 fs/dlm/lockspace.c:632
1 lock held by dlm_recoverd/5846:
 #0: ffff88807ee9aa18 (&ls->ls_in_recovery){+.+.}-{4:4}, at: dlm_recoverd+0xbd/0x1f90 fs/dlm/recoverd.c:400

=============================================

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 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x141/0x190 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xcb1/0x1030 kernel/hung_task.c:561
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:__lock_acquire+0x4c4/0x1a40 kernel/locking/lockdep.c:5210
Code: e8 f1 ee ff ff 85 c0 0f 84 e9 fe ff ff 44 8b 1d 62 17 8e 19 45 85 db 75 11 4d 63 e4 4c 0f a3 25 32 6b 85 14 0f 83 69 0b 00 00 <48> 8b b5 90 0b 00 00 45 85 ed 0f 84 93 01 00 00 c7 44 24 48 00 00
RSP: 0018:ffffc90000007990 EFLAGS: 00000047
RAX: 0000000000000001 RBX: ffffffff8e892048 RCX: 0000000000000100
RDX: 0000000000000000 RSI: ffffffff8e892048 RDI: ffffffff8e891480
RBP: ffffffff8e891480 R08: 0000000000000001 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000040
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888123dd8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005575c1ea00c8 CR3: 000000000e994000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825
 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:382
 raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:667
 raw_spin_rq_lock kernel/sched/sched.h:1653 [inline]
 _raw_spin_rq_lock_irqsave kernel/sched/sched.h:1682 [inline]
 sched_balance_rq+0x1e04/0x3b10 kernel/sched/fair.c:13465
 sched_balance_domains+0x4e9/0xb80 kernel/sched/fair.c:13800
 _nohz_idle_balance.isra.0+0x62d/0x8c0 kernel/sched/fair.c:14228
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:267 [inline]
 sysvec_call_function_single+0xa3/0xc0 arch/x86/kernel/smp.c:267
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: d6 8b 02 c3 cc cc cc cc 0f 1f 00 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 a3 5f 10 00 fb f4 <e9> 3c 4a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e807e10 EFLAGS: 00000242
RAX: 0000000000156f89 RBX: ffffffff8e891480 RCX: ffffffff8bbb42d5
RDX: 0000000000000000 RSI: ffffffff8e1a8186 RDI: ffffffff8c402680
RBP: fffffbfff1d12290 R08: 0000000000000001 R09: ffffed101708678d
R10: ffff8880b8433c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffffff1d00fc6 R15: dffffc0000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:768
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
 rest_init+0x251/0x260 init/main.c:717
 start_kernel+0x48e/0x490 init/main.c:1175
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x158
 </TASK>