INFO: task syz.0.10:5877 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.10 state:D stack:26568 pid:5877 ppid:5775 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2c6/0x5a0 kernel/sched/completion.c:148
io_wq_exit_workers io_uring/io-wq.c:1267 [inline]
io_wq_put_and_exit+0x493/0x820 io_uring/io-wq.c:1295
io_uring_clean_tctx+0x12f/0x1b0 io_uring/tctx.c:204
io_uring_cancel_generic+0x610/0x6c0 io_uring/io_uring.c:3507
io_uring_files_cancel include/linux/io_uring.h:69 [inline]
do_exit+0x5f4/0x2530 kernel/exit.c:836
do_group_exit+0x22d/0x2f0 kernel/exit.c:1032
get_signal+0x12a6/0x1390 kernel/signal.c:2911
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f563a19e019
RSP: 002b:00007f563b08b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f563a425fa8 RCX: 00007f563a19e019
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f563a425fa8
RBP: 00007f563a425fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f563a426038 R14: 00007ffeeb122fd0 R15: 00007ffeeb1230b8
INFO: task iou-wrk-5877:5878 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:iou-wrk-5877 state:D stack:25456 pid:5878 ppid:5775 flags:0x00024004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
do_uevent+0x1ed/0x490 fs/dlm/lockspace.c:210
new_lockspace fs/dlm/lockspace.c:633 [inline]
__dlm_new_lockspace+0x1dca/0x2360 fs/dlm/lockspace.c:693
device_create_lockspace+0xc8/0x350 fs/dlm/user.c:430
device_write+0x875/0xed0 fs/dlm/user.c:622
loop_rw_iter+0x368/0x5b0 io_uring/rw.c:-1
io_write+0x12d5/0x1900 io_uring/rw.c:980
io_issue_sqe+0x295/0xc60 io_uring/io_uring.c:1869
io_wq_submit_work+0x409/0x9d0 io_uring/io_uring.c:1956
io_worker_handle_work+0x7a8/0x10b0 io_uring/io-wq.c:602
io_wq_worker+0x47d/0xf10 io_uring/io-wq.c:656
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:5/61:
2 locks held by kworker/u4:8/1331:
2 locks held by getty/5531:
#0: ffff88802d62d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
1 lock held by iou-wrk-5877/5878:
#0: ffffffff973c9a68 (&ls_lock){+.+.}-{3:3}, at: __dlm_new_lockspace+0xb1/0x2360 fs/dlm/lockspace.c:687
1 lock held by dlm_recoverd/5882:
#0: ffff8880271c0aa8 (&ls->ls_in_recovery){+.+.}-{3:3}, at: dlm_recoverd+0xa5/0x1e50 fs/dlm/recoverd.c:310
3 locks held by syz.4.122/7051:
2 locks held by syz.5.123/7052:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7052 Comm: syz.5.123 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:228 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:240 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:__lock_acquire+0x1077/0x7d80 kernel/locking/lockdep.c:5133
Code: c0 0f 85 eb 0f 00 00 8b 03 89 c3 81 e3 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 00 b5 1e 91 be 08 00 00 00 e8 c9 5a 77 00 <48> 0f a3 1d 11 1a b6 0f 0f 83 48 01 00 00 48 69 c3 d0 00 00 00 48
RSP: 0018:ffffc900034570a0 EFLAGS: 00000056
RAX: 0000000000000001 RBX: 0000000000000545 RCX: ffffffff81689ae7
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff911eb5a8
RBP: ffffc900034572e8 R08: ffffffff911eb5af R09: 1ffffffff223d6b5
R10: dffffc0000000000 R11: fffffbfff223d6b6 R12: 000000007eb41b4b
R13: ffff88801ef50000 R14: 00000000468dfbac R15: ffff88801ef50b50
FS: 00007f8deebff6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055af07f29950 CR3: 000000006a1fb000 CR4: 00000000003506f0
Call Trace:
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__fs_reclaim_acquire mm/page_alloc.c:3600 [inline]
fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:3614
might_alloc include/linux/sched/mm.h:303 [inline]
prepare_alloc_pages+0x156/0x5b0 mm/page_alloc.c:4271
__alloc_pages+0x134/0x460 mm/page_alloc.c:4490
__folio_alloc+0x10/0x20 mm/page_alloc.c:4533
vma_alloc_folio+0x474/0x8f0 mm/mempolicy.c:2240
shmem_alloc_folio+0x1a9/0x2a0 mm/shmem.c:1679
shmem_alloc_and_acct_folio+0x1cb/0x6c0 mm/shmem.c:1704
shmem_get_folio_gfp+0xe1d/0x2b40 mm/shmem.c:2041
shmem_get_folio mm/shmem.c:2164 [inline]
shmem_write_begin+0xf2/0x430 mm/shmem.c:2706
generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4036
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x474/0x9a0 fs/read_write.c:584
ksys_write+0x151/0x260 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8dedd5e84e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f8deebfeda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8deebff6c0 RCX: 00007f8dedd5e84e
RDX: 0000000002000000 RSI: 00007f8de3bf7000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f8deebfeee0 R14: 00007f8deebfeea0 R15: 00007f8de3bf7000