INFO: task syz.3.3029:18220 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.3.3029 state:D stack:28800 pid:18220 tgid:18213 ppid:13097 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7047 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7062
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119
rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write_nested+0x1c6/0x210 kernel/locking/rwsem.c:1752
inode_lock_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2908 [inline]
start_dirop fs/namei.c:2932 [inline]
filename_unlinkat+0x2a7/0x610 fs/namei.c:5543
__do_sys_unlink fs/namei.c:5597 [inline]
__se_sys_unlink+0x2e/0x140 fs/namei.c:5594
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa96499c799
RSP: 002b:00007fa96587d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fa964c16090 RCX: 00007fa96499c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007fa964a32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa964c16128 R14: 00007fa964c16090 R15: 00007ffeb1a380d8
INFO: task syz.3.3029:18225 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.3029 state:D stack:27712 pid:18225 tgid:18213 ppid:13097 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7047 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7062
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119
rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write_nested+0x1c6/0x210 kernel/locking/rwsem.c:1752
inode_lock_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2908 [inline]
start_dirop fs/namei.c:2932 [inline]
filename_create+0x200/0x370 fs/namei.c:4944
filename_mkdirat+0xd2/0x510 fs/namei.c:5281
__do_sys_mkdirat fs/namei.c:5309 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5306
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa96499b607
RSP: 002b:00007fa96585be58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fa96585bee0 RCX: 00007fa96499b607
RDX: 00000000000001ff RSI: 00002000000001c0 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007fa96585bea0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/36:
#0: ffff888032c51140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc90000ac7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4198
2 locks held by kworker/0:2/807:
2 locks held by kworker/u8:7/1106:
#0: ffff88801e70b940 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc900055bfc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
2 locks held by getty/5604:
#0: ffff8880374d10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
6 locks held by kworker/u8:16/7443:
#0: ffff88801c2b6140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc90002557c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffffffff8fbc6d68 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675
#3: ffff8880336fa0e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#3: ffff8880336fa0e0 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline]
#3: ffff8880336fa0e0 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x126/0x420 net/devlink/core.c:555
#4: ffff8880336f8258 (&devlink->lock_key#7){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline]
#4: ffff8880336f8258 (&devlink->lock_key#7){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline]
#4: ffff8880336f8258 (&devlink->lock_key#7){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x13f/0x420 net/devlink/core.c:555
#5: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#5: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2164
2 locks held by syz.3.3029/18220:
#0: ffff8880771be410 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2908 [inline]
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2932 [inline]
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: filename_unlinkat+0x2a7/0x610 fs/namei.c:5543
2 locks held by syz.3.3029/18225:
#0: ffff8880771be410 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2908 [inline]
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2932 [inline]
#1: ffff888058c276d8 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4944
2 locks held by syz-executor/18407:
2 locks held by syz.7.3448/20008:
#0: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
#1: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
3 locks held by kworker/1:7/20189:
#0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc90003c2fc40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
4 locks held by syz.2.3506/20216:
#0: ffff88805aab0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88805aab0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88805aab00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#2: ffffffff8fd62100 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8fd62100 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644
#3: ffff8880333f0af0 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1751
1 lock held by syz.5.3545/20390:
#0: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fbd5d80 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
1 lock held by dhcpcd-run-hook/20398:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
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+0x1002/0x1060 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20188 Comm: kworker/1:2 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: 0x0 (events)
RIP: 0010:lookup_object lib/debugobjects.c:445 [inline]
RIP: 0010:debug_object_deactivate+0xcf/0x3a0 lib/debugobjects.c:903
Code: 6d 00 41 ff c4 4d 85 ed 74 38 49 8d 5d 18 48 89 dd 48 c1 ed 03 42 80 7c 35 00 00 74 08 48 89 df e8 d6 20 74 fd 4c 39 3b 74 41 <4c> 89 e8 48 c1 e8 03 42 80 3c 30 00 74 c6 4c 89 ef e8 bb 20 74 fd
RSP: 0018:ffffc90003687ae8 EFLAGS: 00000006
RAX: 1ffff110139872bd RBX: ffff888079af2830 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90003687a40
RBP: 1ffff1100f35e506 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520006d0f48 R12: 000000000000000a
R13: ffff888079af2818 R14: dffffc0000000000 R15: ffff8880336f85b0
FS: 0000000000000000(0000) GS:ffff888125535000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559e9db2b950 CR3: 000000000e54a000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
debug_work_deactivate kernel/workqueue.c:675 [inline]
process_one_work+0x1e0/0x1780 kernel/workqueue.c:3210
process_scheduled_works kernel/workqueue.c:3380 [inline]
worker_thread+0xba8/0x11e0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245