INFO: task syz.5.11665:5891 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.11665 state:D stack:28424 pid:5891 tgid:5890 ppid:29756 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
cgroup_lock_and_drain_offline+0x51a/0x650 kernel/cgroup/cgroup.c:3275
cgroup_kn_lock_live+0x120/0x230 kernel/cgroup/cgroup.c:1715
cgroup_subtree_control_write+0x4b5/0x1080 kernel/cgroup/cgroup.c:3577
cgroup_file_write+0x331/0x8f0 kernel/cgroup/cgroup.c:4316
kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f42d4d9de99
RSP: 002b:00007f42d5c64028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f42d5025fa0 RCX: 00007f42d4d9de99
RDX: 0000000000000008 RSI: 0000200000000300 RDI: 0000000000000005
RBP: 00007f42d4e33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f42d5026038 R14: 00007f42d5025fa0 R15: 00007ffebd641238
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5372:
#0: ffff8880366c00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
1 lock held by udevd/6507:
3 locks held by syz.5.11665/5891:
#0: ffff888030c9c0f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888033fe0450 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888033fe0450 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffff88807212c880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d8/0x540 fs/kernfs/file.c:336
3 locks held by syz.9.12218/7388:
#0: ffff88807aaf8b70 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888033fe0450 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888033fe0450 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffff888052deac80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d8/0x540 fs/kernfs/file.c:336
1 lock held by syz-executor/7682:
#0: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz.4.12481/8350:
#0: ffff888078fcdcf0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
#1: ffff888033fe0450 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888033fe0450 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffff88806b204c80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d8/0x540 fs/kernfs/file.c:336
1 lock held by syz-executor/8471:
#0: ffffffff9002d340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff9002d340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff9002d340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158
2 locks held by syz-executor/8655:
#0: ffffffff8f7707e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8f7707e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8f7707e8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff9002d340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff9002d340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff9002d340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158
4 locks held by dhcpcd-run-hook/8907:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7682 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:get_dep_list kernel/locking/lockdep.c:1572 [inline]
RIP: 0010:__bfs_next kernel/locking/lockdep.c:1702 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1752 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x173e/0x2cf0 kernel/locking/lockdep.c:5237
Code: 8d 84 24 90 00 00 00 48 89 05 1e 7b d2 14 31 ff 45 31 ff 4d 85 ff 4c 8b 6c 24 08 74 2e 49 8b 47 30 48 85 c0 74 25 48 8b 40 10 <48> 83 c0 30 49 8b 0f 48 89 8c 24 d8 00 00 00 48 39 c1 74 0d 4c 8b
RSP: 0018:ffffc900067e6648 EFLAGS: 00000086
RAX: ffffffff94194078 RBX: 00000000000003fd RCX: 00000000000d9968
RDX: ffffffff971d3cb8 RSI: ffff88801bf30ce0 RDI: 00000000000003fd
RBP: a2abe1e00bc6a6d5 R08: ffffc900067e6610 R09: 0000000000000020
R10: 0000000000000000 R11: ffffffff81a32270 R12: 000000000000069b
R13: ffff88801bf30ce0 R14: ffff88801bf30000 R15: ffffffff97348b58
FS: 0000555587be5500(0000) GS:ffff888124f50000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8ec2c1c120 CR3: 000000003dff0000 CR4: 0000000000350ef0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
debug_object_activate+0xb7/0x420 lib/debugobjects.c:873
debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline]
debug_activate kernel/time/hrtimer.c:528 [inline]
remove_and_enqueue_same_base kernel/time/hrtimer.c:1259 [inline]
__hrtimer_start_range_ns kernel/time/hrtimer.c:1402 [inline]
hrtimer_start_range_ns_common+0x4c1/0xb90 kernel/time/hrtimer.c:1481
hrtimer_start_range_ns+0x111/0x3e0 kernel/time/hrtimer.c:1503
hrtimer_start include/linux/hrtimer.h:223 [inline]
hrtick_cond_restart kernel/sched/core.c:939 [inline]
hrtick_schedule_exit kernel/sched/core.c:1001 [inline]
finish_lock_switch kernel/sched/core.c:5240 [inline]
finish_task_switch+0x3c4/0xc60 kernel/sched/core.c:5359
context_switch kernel/sched/core.c:5513 [inline]
__schedule+0x17e1/0x56c0 kernel/sched/core.c:7234
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline]
_raw_spin_unlock_irq+0x45/0x50 kernel/locking/spinlock.c:206
spin_unlock_irq include/linux/spinlock.h:402 [inline]
blk_insert_flush+0x419/0x560 block/blk-flush.c:458
blk_mq_submit_bio+0x1a66/0x2a40 block/blk-mq.c:3194
__submit_bio_noacct_mq block/blk-core.c:756 [inline]
submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790
__submit_merged_bio+0x258/0x6a0 fs/f2fs/data.c:598
__f2fs_submit_merged_write fs/f2fs/data.c:695 [inline]
__submit_merged_write_cond fs/f2fs/data.c:719 [inline]
f2fs_submit_merged_write+0x27d/0x380 fs/f2fs/data.c:737
commit_checkpoint fs/f2fs/checkpoint.c:1631 [inline]
do_checkpoint+0x2490/0x3f20 fs/f2fs/checkpoint.c:1814
f2fs_write_checkpoint+0x17f1/0x2710 fs/f2fs/checkpoint.c:1940
f2fs_issue_checkpoint+0x424/0x6f0 fs/f2fs/checkpoint.c:2108
sync_filesystem+0x1cf/0x230 fs/sync.c:66
generic_shutdown_super+0x77/0x2d0 fs/super.c:626
kill_block_super+0x44/0x90 fs/super.c:1665
kill_f2fs_super+0x3eb/0x700 fs/f2fs/super.c:5595
deactivate_locked_super+0xbc/0x130 fs/super.c:477
cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff44519f0d7
Code: a2 c7 05 1c 26 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc4115d258 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007ff44523330a RCX: 00007ff44519f0d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc4115d310
RBP: 00007ffc4115d310 R08: 00007ffc4115e310 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc4115e3a0
R13: 00007ff44523330a R14: 00000000001818f4 R15: 00007ffc4115e3e0