INFO: task kworker/u8:4:67 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4 state:D stack:19704 pid:67 tgid:67 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:2)
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
io_schedule+0x7f/0xd0 kernel/sched/core.c:8109
TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline]
txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:376
jfs_commit_inode+0x1b3/0x530 fs/jfs/inode.c:107
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75d/0x10e0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x97f/0x1980 fs/fs-writeback.c:2054
wb_writeback+0x445/0xb00 fs/fs-writeback.c:2239
wb_do_writeback fs/fs-writeback.c:2386 [inline]
wb_workfn+0x3fd/0xf20 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3308 [inline]
process_scheduled_works+0xb68/0x1910 kernel/workqueue.c:3399
worker_thread+0xa90/0x1040 kernel/workqueue.c:3485
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
INFO: task syz-executor:5834 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-executor state:D stack:22160 pid:5834 tgid:5834 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
__writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2845
sync_filesystem+0xa2/0x250 fs/sync.c:54
generic_shutdown_super+0x77/0x2d0 fs/super.c:625
kill_block_super+0x44/0x90 fs/super.c:1725
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
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:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__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:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f157dbbda57
RSP: 002b:00007ffd50546d68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f157dc52048 RCX: 00007f157dbbda57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd50546e20
RBP: 00007ffd50546e20 R08: 00007ffd50547e20 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd50547eb0
R13: 00007f157dc52048 R14: 0000000000086876 R15: 00007ffd50547ef0
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by kworker/u8:4/67:
#0: ffff88801fa8d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline]
#0: ffff88801fa8d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399
#1: ffffc9000152fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline]
#1: ffffc9000152fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399
3 locks held by kworker/0:2/820:
#0: ffff88801a052938 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline]
#0: ffff88801a052938 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399
#1: ffffc90004987c40 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline]
#1: ffffc90004987c40 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399
#2: ffff88802a13c210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802a13c210 (&dev->mutex){....}-{4:4}, at: usb_remote_wakeup+0x23/0x120 drivers/usb/core/hub.c:3886
2 locks held by udevd/5204:
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __d_lookup+0x66/0x780 fs/dcache.c:2512
#1: ffff88803cbbc7f0 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#1: ffff88803cbbc7f0 (&lockref->lock){+.+.}-{3:3}, at: __d_lookup+0x23e/0x780 fs/dcache.c:2519
2 locks held by getty/5588:
#0: ffff8880329740a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5834:
#0: ffff88803b7140d0 (&type->s_umount_key#62){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803b7140d0 (&type->s_umount_key#62){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88803b7140d0 (&type->s_umount_key#62){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
7 locks held by kworker/u8:3/15203:
#0: ffff88801b296138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline]
#0: ffff88801b296138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399
#1: ffffc90011157c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline]
#1: ffffc90011157c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399
#2: ffffffff8f370ce0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673
#3: ffff888035e99160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff888035e99160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline]
#3: ffff888035e99160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:555
#4: ffff88803c3ce310 (&devlink->lock_key){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline]
#4: ffff88803c3ce310 (&devlink->lock_key){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline]
#4: ffff88803c3ce310 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:555
#5: ffffffff8f37f5f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x13a/0x830 drivers/net/netdevsim/netdev.c:1185
#6: ffff88805e4d8f40 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2801 [inline]
#6: ffff88805e4d8f40 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x588/0x22b0 net/core/dev.c:12424
2 locks held by kworker/u8:16/15219:
#0: ffff88801a094138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline]
#0: ffff88801a094138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399
#1: ffffc9001b907c40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline]
#1: ffffc9001b907c40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399
3 locks held by syz-executor/16777:
#0: ffff88803f288a60 (&sb->s_type->i_lock_key){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#0: ffff88803f288a60 (&sb->s_type->i_lock_key){+.+.}-{3:3}, at: filemap_remove_folio+0xd0/0x200 mm/filemap.c:255
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#2: ffff88803f288c38 (&xa->xa_lock#9){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff88803f288c38 (&xa->xa_lock#9){+.+.}-{3:3}, at: filemap_remove_folio+0xdc/0x200 mm/filemap.c:256
2 locks held by udevd/17677:
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: dput+0x37/0x1a0 fs/dcache.c:971
#1: ffff88803cbbc7f0 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#1: ffff88803cbbc7f0 (&lockref->lock){+.+.}-{3:3}, at: fast_dput+0xdd/0x430 fs/dcache.c:876
2 locks held by syz-executor/20505:
#0: ffffffff8f370ce0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:575
#1: ffffffff8f37f5f8 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2d7/0x840 net/ipv4/ip_tunnel.c:1146
5 locks held by syz.3.6033/20623:
#0: ffff88802a410480 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88805fdd2600 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#1: ffff88805fdd2600 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: open_last_lookups fs/namei.c:4608 [inline]
#1: ffff88805fdd2600 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4855
#2: ffff88802a4120d8 (&sbi->s_lock){+.+.}-{4:4}, at: exfat_lookup+0x187/0x1950 fs/exfat/namei.c:724
#3: ffff8880b893d018 ((lock)#5){+.+.}-{3:3}, at: trylock_stock+0x103/0x350 mm/memcontrol.c:3134
#4: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#4: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#4: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_trylock kernel/locking/spinlock_rt.c:110 [inline]
#4: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x10c/0x2b0 kernel/locking/spinlock_rt.c:118
4 locks held by syz.1.6040/20639:
#0: ffff88803486deb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline]
#0: ffff88803486deb0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x194/0x9e0 mm/mmap.c:1284
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#1: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290
#2: ffff888029b13958 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff888029b13958 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
#3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8dfc8100 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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+0xfd3/0x1030 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15202 Comm: kworker/u8:2 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3803 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3823 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3878 [inline]
RIP: 0010:__lock_acquire+0xb17/0x2cf0 kernel/locking/lockdep.c:5239
Code: cb ef 0d 48 c7 c6 c5 22 76 8d 67 48 0f b9 3a 90 48 bb eb 83 b5 80 46 86 c8 61 48 0f af dd 48 c1 eb 2d 48 8b 04 dd 60 c3 39 93 <48> 85 c0 0f 94 c1 48 83 c0 f8 0f 94 c2 08 ca 0f 84 1c 01 00 00 e8
RSP: 0018:ffffc90011147420 EFLAGS: 00000803
RAX: ffffffff93819918 RBX: 0000000000056aa4 RCX: 0000000000040000
RDX: 00000000a1164082 RSI: 00000000ca726525 RDI: ffff888069551ec0
RBP: 60c85b37dc361e5e R08: ffffffff8b37d637 R09: ffff88801a089c18
R10: dffffc0000000000 R11: fffffbfff1f1a23f R12: ffff888069552bd0
R13: ffff888069552bd0 R14: ffff888069551ec0 R15: 0000000000000007
FS: 0000000000000000(0000) GS:ffff8881261c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f59f229d053 CR3: 000000000ddb6000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
rtlock_slowlock kernel/locking/rtmutex.c:1910 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x157/0x400 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:45 [inline]
pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
__text_poke+0x2d3/0x9a0 arch/x86/kernel/alternative.c:2587
text_poke arch/x86/kernel/alternative.c:2672 [inline]
smp_text_poke_batch_finish+0x923/0x1160 arch/x86/kernel/alternative.c:3005
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:913
process_one_work kernel/workqueue.c:3308 [inline]
process_scheduled_works+0xb68/0x1910 kernel/workqueue.c:3399
worker_thread+0xa90/0x1040 kernel/workqueue.c:3485
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