INFO: task segctord:4502 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:segctord state:D stack:28856 pid: 4502 ppid: 2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc87/0x1260 kernel/locking/rwsem.c:1165
nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2562 [inline]
nilfs_segctor_thread+0x518/0x1180 fs/nilfs2/segment.c:2647
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:2/145:
2 locks held by kworker/u4:3/155:
2 locks held by getty/3953:
#0: ffff88807f023098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:3/4243:
#0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#1:
ffff8880b9127888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
#2:
ffff888016e8c5a8
(&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
3 locks held by kworker/1:23/4429:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000303fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffff888075534240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26a/0x33e0 drivers/net/netdevsim/fib.c:1480
2 locks held by syz.0.17/4496:
1 lock held by segctord/4502:
#0: ffff88801dc3a2a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz.1.18/4579:
1 lock held by segctord/4580:
#0:
ffff8880257a22a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz.2.19/4597:
1 lock held by segctord/4598:
#0: ffff88807c27b2a0
(
&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz.3.20/4615:
1 lock held by segctord/4616:
#0:
ffff88807bc422a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz.4.21/4646:
1 lock held by segctord/4647:
#0:
ffff888078bfb2a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz.5.22/4672:
1 lock held by segctord/4673:
#0: ffff888076d732a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz.6.23/4697:
1 lock held by segctord/4698:
#0: ffff8880755822a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x252/0x4c0 fs/nilfs2/segment.c:357
2 locks held by syz-executor/4707:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4488 Comm: kworker/u4:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound linkwatch_event
RIP: 0010:can_migrate_task+0x282/0xc60 kernel/sched/fair.c:8078
Code: 66 00 49 0f a3 2e 0f 83 85 00 00 00 48 8b 04 24 4c 8d 78 40 4c 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 49 89 de 0f 85 95 06 00 00 <41> 8b 1f 89 d8 83 e0 fe 41 89 07 4d 8d 7c 24 34 4c 89 f8 48 c1 e8
RSP: 0018:ffffc90000dd0858 EFLAGS: 00000046
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff81580e6a
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88802a62bfa8
RBP: 0000000000000001 R08: ffff88802a62bfaf R09: 1ffff110054c57f5
R10: dffffc0000000000 R11: ffffed10054c57f6 R12: ffff88802a62bb80
R13: 1ffff920001ba18e R14: dffffc0000000000 R15: ffffc90000dd0ca0
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f32485f1e9c CR3: 0000000076969000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
detach_tasks kernel/sched/fair.c:8209 [inline]
load_balance+0x31ef/0x4e60 kernel/sched/fair.c:10252
rebalance_domains+0x489/0xb30 kernel/sched/fair.c:10632
handle_softirqs+0x339/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:console_trylock_spinning+0x301/0x370 kernel/printk/printk.c:1909
Code: 85 db 74 89 e8 50 e7 18 00 fb 31 c0 eb 48 e8 46 e7 18 00 e8 01 2f 5c 08 48 85 db 74 d1 e8 37 e7 18 00 fb 48 c7 c7 e0 35 31 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 68 da 39 60
RSP: 0018:ffffc900030df7c0 EFLAGS: 00000293
RAX: ffffffff816039d9 RBX: 0000000000000200 RCX: ffff888024e71dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c3135e0
RBP: ffffc900030df890 R08: ffffffff901d40cf R09: 1ffffffff203a819
R10: dffffc0000000000 R11: fffffbfff203a81a R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff9200061bef8
vprintk_emit+0xa7/0x150 kernel/printk/printk.c:2273
_printk+0xda/0x130 kernel/printk/printk.c:2299
addrconf_notify+0xa5b/0xf00 net/ipv6/addrconf.c:3656
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
netdev_state_change+0xe0/0x160 net/core/dev.c:1453
linkwatch_do_dev+0x10d/0x160 net/core/link_watch.c:167
__linkwatch_run_queue+0x4b1/0x7c0 net/core/link_watch.c:213
linkwatch_event+0x48/0x50 net/core/link_watch.c:252
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>