INFO: task syz.2.352:7563 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.352 state:D stack:25688 pid:7563 tgid:7553 ppid:5599 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7277
__schedule_loop kernel/sched/core.c:7354 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7369
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
vfs_write+0x2aa/0x1050 fs/read_write.c:685
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff11479e159
RSP: 002b:00007ff1129d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff114a26090 RCX: 00007ff11479e159
RDX: 0000000000000068 RSI: 0000200000000100 RDI: 0000000000000004
RBP: 00007ff11483506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff114a26128 R14: 00007ff114a26090 R15: 00007ffe6ec99d58
Showing all locks held in the system:
locks held by khungtaskd/32: 1, last CPU#0:
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871
locks held by getty/5355: 2, on CPU#0:
#0: ffff88801d7300a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032262e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by kworker/0:6/5762: 5, last CPU#0:
#0: ffff888024290d40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90003fdfd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffff88802aff41d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#2: ffff88802aff41d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bb/0x4420 drivers/usb/core/hub.c:5912
#3: ffff88802b438568 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3265 [inline]
#3: ffff88802b438568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5477 [inline]
#3: ffff88802b438568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
#3: ffff88802b438568 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5884 [inline]
#3: ffff88802b438568 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2b3e/0x4420 drivers/usb/core/hub.c:5966
#4: ffff88802af95660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5478 [inline]
#4: ffff88802af95660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
#4: ffff88802af95660 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5884 [inline]
#4: ffff88802af95660 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2b67/0x4420 drivers/usb/core/hub.c:5966
locks held by syz.2.352/7563: 1, on CPU#0:
#0: ffffffff9ba31900 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xb8/0x1fa0 fs/dlm/lockspace.c:632
locks held by dlm_recoverd/7568: 1, on CPU#0:
#0: ffff888036caaa18 (&ls->ls_in_recovery){+.+.}-{4:4}, at: dlm_recoverd+0xbd/0x1f90 fs/dlm/recoverd.c:400
locks held by syz.0.597/8715: 2, last CPU#0:
#0: ffff88807e61a460 (sb_writers#6){.+.+}-{0:0}, at: get_signal+0x1f2a/0x21e0 kernel/signal.c:3036
#1: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8edec4a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by syz.7.626/8827: 1, last CPU#0:
#0: ffff88802ee8d270 (&u->iolock){+.+.}-{4:4}, at: __unix_dgram_recvmsg+0x255/0xc30 net/unix/af_unix.c:2587
locks held by syz.5.631/8841: 1, last CPU#0:
#0: ffff8880272fb070 (&u->iolock){+.+.}-{4:4}, at: __unix_dgram_recvmsg+0x255/0xc30 net/unix/af_unix.c:2587
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
Call Trace:
__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:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245