INFO: task segctord:6285 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:segctord state:D stack:28536 pid:6285 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
rwsem_down_write_slowpath+0xc3f/0x1020 kernel/locking/rwsem.c:1178
__down_write_common kernel/locking/rwsem.c:1306 [inline]
__down_write kernel/locking/rwsem.c:1315 [inline]
down_write+0x1b9/0x200 kernel/locking/rwsem.c:1574
nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2561 [inline]
nilfs_segctor_thread+0x520/0x1050 fs/nilfs2/segment.c:2646
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
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/u4:2/42:
#0: ffff88801faf7538 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88801faf7538 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc90000b2fd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90000b2fd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#2: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004
2 locks held by kworker/u4:7/3455:
#0: ffff8880b8e3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x9c/0x130 kernel/sched/core.c:567
#1: ffffc9000cfb7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000cfb7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
2 locks held by getty/5525:
#0: ffff88814ddb80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
2 locks held by kworker/0:6/5834:
#0:
ffff888017c72538
(
(wq_completion)rcu_gp
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc9000492fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000492fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
6 locks held by syz.3.97/6281:
1 lock held by segctord/6285:
#0: ffff88805f74e2a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x24a/0x4b0 fs/nilfs2/segment.c:357
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6281 Comm: syz.3.97 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x17/0x80 kernel/kcov.c:320
Code: 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d a0 ce 7c 7e 65 8b 15 a1 ce 7c 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00
RSP: 0018:ffffc9000ba966f0 EFLAGS: 00000246
RAX: ffffffff8a746ae8 RBX: ffff0a1000000600 RCX: ffff888030771e00
RDX: 0000000080000001 RSI: 000000007fffffff RDI: 0000000000000000
RBP: 000000007fffffff R08: ffffc9000ba969cd R09: 1ffff92001752d39
R10: dffffc0000000000 R11: fffff52001752d3a R12: ffffc9008ba969bf
R13: ffffc9000ba969ce R14: ffffc9000ba969c0 R15: dffffc0000000000
FS: 00007fe2264566c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6dd4429d58 CR3: 000000007556e000 CR4: 00000000003506e0
Call Trace:
vsnprintf+0x1ab8/0x1ba0 lib/vsprintf.c:2894
sprintf+0xe8/0x140 lib/vsprintf.c:3027
print_time kernel/printk/printk.c:1327 [inline]
info_print_prefix+0x16c/0x360 kernel/printk/printk.c:1353
record_print_text+0x182/0x4a0 kernel/printk/printk.c:1402
printk_get_next_message+0x2ab/0x980 kernel/printk/printk.c:2876
console_emit_next_record kernel/printk/printk.c:2911 [inline]
console_flush_all+0x38d/0xcf0 kernel/printk/printk.c:3000
console_unlock+0xad/0x350 kernel/printk/printk.c:3069
vprintk_emit+0x497/0x610 kernel/printk/printk.c:2341
_printk+0xde/0x130 kernel/printk/printk.c:2366
__nilfs_msg+0x374/0x450 fs/nilfs2/super.c:79
nilfs_sufile_updatev+0x21c/0x640 fs/nilfs2/sufile.c:174
nilfs_sufile_freev fs/nilfs2/sufile.h:87 [inline]
nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1247 [inline]
nilfs_segctor_collect fs/nilfs2/segment.c:1535 [inline]
nilfs_segctor_do_construct+0x1f3e/0x69e0 fs/nilfs2/segment.c:2091
nilfs_segctor_construct+0x170/0x690 fs/nilfs2/segment.c:2454
nilfs_clean_segments+0x3cf/0xab0 fs/nilfs2/segment.c:2528
nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:946 [inline]
nilfs_ioctl+0x204f/0x21b0 fs/nilfs2/ioctl.c:1310
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
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: 0033:0x7fe22559ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe226456028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe225815fa0 RCX: 00007fe22559ce59
RDX: 0000200000000640 RSI: 0000000040786e88 RDI: 0000000000000004
RBP: 00007fe225632e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe225816038 R14: 00007fe225815fa0 R15: 00007ffdc2adbed8