INFO: task syz-executor:8458 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21648 pid:8458 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
wb_wait_for_completion+0x173/0x2a0 fs/fs-writeback.c:192
sync_inodes_sb+0x1c9/0xa10 fs/fs-writeback.c:2778
sync_filesystem+0x171/0x220 fs/sync.c:64
generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
kill_block_super+0x44/0x90 fs/super.c:1660
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259
task_work_run+0x1d4/0x260 kernel/task_work.c:245
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x95a/0x2460 kernel/exit.c:883
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
__do_sys_exit_group kernel/exit.c:1035 [inline]
__se_sys_exit_group kernel/exit.c:1033 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc87f19c629
RSP: 002b:00007ffec1ed9f28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fc87f231f50 RCX: 00007fc87f19c629
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 000000000000000c R08: 0000000000000000 R09: 00007fc87f231ef0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffec1edb1e0
R13: 00007fc87f231ef0 R14: 000055557e1604e8 R15: 00007ffec1edc2b0
Showing all locks held in the system:
3 locks held by pool_workqueue_/3:
2 locks held by kworker/u4:0/11:
1 lock held by khungtaskd/28:
#0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:3/48:
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#1: ffffc90000b97d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000b97d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#2: ffffffff8e3c0348 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
5 locks held by kworker/u4:5/1092:
#0: ffff888017c73938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017c73938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#1: ffffc900049afd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900049afd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#2: ffffffff8e3b3310 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x14c/0xbb0 net/core/net_namespace.c:606
#3: ffffffff8e3c0348 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1c/0x1c0 drivers/net/wireguard/device.c:421
#4: ffff888030b713e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_netns_pre_exit+0xb0/0x1c0 drivers/net/wireguard/device.c:426
2 locks held by getty/5529:
#0: ffff88802d63a0a0 (&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+0x433/0x1390 drivers/tty/n_tty.c:2217
2 locks held by kworker/0:3/5807:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#1: ffffc9000487fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000487fd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
2 locks held by syz-executor/8458:
#0: ffff888059ae40e0 (&type->s_umount_key#63){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888059ae40e0 (&type->s_umount_key#63){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888059ae40e0 (&type->s_umount_key#63){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffff888021d167d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline]
#1: ffff888021d167d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1ad/0xa10 fs/fs-writeback.c:2776
1 lock held by segctord/10213:
2 locks held by kworker/1:4/12115:
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
#1: ffffc90003227d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90003227d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711
4 locks held by syz.8.1921/12568:
#0: ffff88807c804e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88807c804e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff88807c8040b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x4c9/0xfa0 net/bluetooth/hci_sync.c:5273
#2: ffffffff8e52d8a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e52d8a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2540
#3: ffff88802215e338 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x70/0x660 net/bluetooth/l2cap_core.c:1763
2 locks held by dhcpcd/12616:
#0: ffff8880789d9a20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff8880789d9a20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff8880789d9a20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420
#1: ffffffff8d137978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#1: ffffffff8d137978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
1 lock held by dhcpcd/12618:
#0: ffff88807a988e20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff88807a988e20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff88807a988e20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420
1 lock held by dhcpcd/12619:
#0: ffff88806b484130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88806b484130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3258
1 lock held by dhcpcd/12620:
#0: ffff88801c7a6130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88801c7a6130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3258
1 lock held by dhcpcd/12621:
#0: ffff88806c4a2130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88806c4a2130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3258
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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+0xf3d/0xf80 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: 10213 Comm: segctord Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:591 [inline]
RIP: 0010:queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
RIP: 0010:do_raw_spin_unlock+0x10b/0x230 kernel/locking/spinlock_debug.c:141
Code: 85 24 01 00 00 41 c7 07 ff ff ff ff 48 c7 c0 40 f1 f9 8c 48 c1 e8 03 42 80 3c 20 00 74 0c 48 c7 c7 40 f1 f9 8c e8 d5 cb 75 00 <48> 83 3d 6d 78 90 0b 00 0f 84 0f 01 00 00 48 89 df e8 0f aa 24 09
RSP: 0018:ffffc9000d0c7448 EFLAGS: 00000046
RAX: 1ffffffff19f3e28 RBX: ffff888017c4ed80 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888017c4ed80
RBP: 1ffff11002f89db1 R08: ffff888017c4ed83 R09: 1ffff11002f89db0
R10: dffffc0000000000 R11: ffffed1002f89db1 R12: dffffc0000000000
R13: 1ffff11002f89db2 R14: ffff888017c4ed90 R15: ffff888017c4ed88
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a511fd74a0 CR3: 000000000cf32000 CR4: 00000000003506e0
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
_raw_spin_unlock_irqrestore+0x79/0x120 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__slab_free+0x34f/0x400 mm/slub.c:3734
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767
slab_alloc_node mm/slub.c:3495 [inline]
slab_alloc mm/slub.c:3503 [inline]
__kmem_cache_alloc_lru mm/slub.c:3510 [inline]
kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519
nilfs_segbuf_new+0x4c/0x250 fs/nilfs2/segbuf.c:38
nilfs_segctor_begin_construction fs/nilfs2/segment.c:1321 [inline]
nilfs_segctor_do_construct+0xafd/0x68a0 fs/nilfs2/segment.c:2084
nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2454
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2562 [inline]
nilfs_segctor_thread+0x536/0x10d0 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