INFO: task kworker/u8:13:8282 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:13 state:D stack:21336 pid:8282 tgid:8282 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1539/0x5080 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75a/0x1060 fs/fs-writeback.c:1813
writeback_sb_inodes+0x92e/0x1940 fs/fs-writeback.c:2041
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2118
wb_writeback+0x459/0xad0 fs/fs-writeback.c:2229
wb_check_old_data_flush fs/fs-writeback.c:2333 [inline]
wb_do_writeback fs/fs-writeback.c:2386 [inline]
wb_workfn+0xaee/0xef0 fs/fs-writeback.c:2414
process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
1 lock held by khungtaskd/31:
#0: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:9/3005:
#0: ffff88801bad6948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254
#1: ffffc9000af87c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8fbb6cd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
2 locks held by getty/5579:
#0: ffff8880375710a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by kworker/u8:13/8282:
#0: ffff888020688148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254
#1: ffffc9000c4ffc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255
#2: ffff8880635460e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff888058a01d40 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
1 lock held by syz-executor/9057:
#0: ffff888077d1e0e0 (&type->s_umount_key#91){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888077d1e0e0 (&type->s_umount_key#91){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888077d1e0e0 (&type->s_umount_key#91){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
3 locks held by kworker/1:1/16012:
#0: ffff88813ff0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254
#1: ffffc90003b2fc40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255
#2: ffffffff8e7663f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e7663f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by ipvs-e:17:0/16356:
#0: ffff8880b843abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655
4 locks held by syz.0.2807/18980:
4 locks held by syz-executor/20319:
#0: ffff88809c290ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88809c290ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88809c2900c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#2: ffffffff8fd527a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8fd527a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644
#3: ffff88802611faf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1755
3 locks held by syz-executor/20654:
#0: ffff888035ddcec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff888035ddcec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff888035ddc0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#2: ffffffff8fd527a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8fd527a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644
1 lock held by syz.2.3119/20721:
#0: ffffffff8e7663f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8e7663f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.5.3120/20729:
1 lock held by dhcpcd/20744:
#0: ffff888033dfe260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1700 [inline]
#0: ffff888033dfe260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3197
1 lock held by dhcpcd/20745:
#0: ffff88802c2de260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1700 [inline]
#0: ffff88802c2de260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3197
1 lock held by dhcpcd-run-hook/20747:
#0: ffff8880b843abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655
4 locks held by dhcpcd-run-hook/20752:
=============================================
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 01/24/2026
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:161 [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:347 [inline]
watchdog+0xff4/0x1040 kernel/hung_task.c:516
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 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: 19680 Comm: kworker/u8:4 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:check_preemption_disabled+0x0/0xe0 lib/smp_processor_id.c:13
Code: c7 a0 6f 27 8c 48 c7 c6 e0 6f 27 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 41 57 41 56 53 65 8b 05 f7 45 76 07 65 8b 0d ec 45 76 07 f7 c1
RSP: 0018:ffffc9000b45f790 EFLAGS: 00000046
RAX: 0000000080000001 RBX: ffffffff8e886580 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff8c276fe0 RDI: ffffffff8c276fa0
RBP: ffffc9000b45f8d0 R08: ffff88813ff39653 R09: 1ffff11027fe72ca
R10: dffffc0000000000 R11: ffffffff816a90f0 R12: dffffc0000000000
R13: ffff88813ff45558 R14: 0000000000000002 R15: ffffffff82226aca
FS: 0000000000000000(0000) GS:ffff888125396000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d9a590a950 CR3: 000000013ff40000 CR4: 00000000003526f0
Call Trace:
unuse_temporary_mm+0x77/0x150 arch/x86/mm/tlb.c:1054
__text_poke+0x6ea/0x9a0 arch/x86/kernel/alternative.c:2602
text_poke arch/x86/kernel/alternative.c:2645 [inline]
smp_text_poke_batch_finish+0xd36/0x1160 arch/x86/kernel/alternative.c:3034
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:899
process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
----------------
Code disassembly (best guess), 5 bytes skipped:
0: 48 c7 c6 e0 6f 27 8c mov $0xffffffff8c276fe0,%rsi
7: eb 1c jmp 0x25
9: 66 66 66 2e 0f 1f 84 data16 data16 cs nopw 0x0(%rax,%rax,1)
10: 00 00 00 00 00
15: 90 nop
16: 90 nop
17: 90 nop
18: 90 nop
19: 90 nop
1a: 90 nop
1b: 90 nop
1c: 90 nop
1d: 90 nop
1e: 90 nop
1f: 90 nop
20: 90 nop
21: 90 nop
22: 90 nop
23: 90 nop
24: 90 nop
* 25: 55 push %rbp <-- trapping instruction
26: 41 57 push %r15
28: 41 56 push %r14
2a: 53 push %rbx
2b: 65 8b 05 f7 45 76 07 mov %gs:0x77645f7(%rip),%eax # 0x7764629
32: 65 8b 0d ec 45 76 07 mov %gs:0x77645ec(%rip),%ecx # 0x7764625
39: f7 .byte 0xf7
3a: c1 .byte 0xc1