INFO: task kworker/u8:13:3307 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:13 state:D stack:20896 pid:3307 tgid:3307 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:7)
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline]
txBegin+0x281/0xbe0 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:1607 [inline]
__writeback_single_inode+0x6af/0xf90 fs/fs-writeback.c:1850
writeback_sb_inodes+0x9db/0x1ab0 fs/fs-writeback.c:2079
wb_writeback+0x41c/0xad0 fs/fs-writeback.c:2264
wb_do_writeback fs/fs-writeback.c:2432 [inline]
wb_workfn+0x437/0x10f0 fs/fs-writeback.c:2477
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
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:16496 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:22744 pid:16496 tgid:16496 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
wb_wait_for_completion+0x3b2/0x700 fs/fs-writeback.c:227
__writeback_inodes_sb_nr+0x246/0x2e0 fs/fs-writeback.c:2933
sync_filesystem+0xa2/0x250 fs/sync.c:54
generic_shutdown_super+0x77/0x2d0 fs/super.c:626
kill_block_super+0x44/0x90 fs/super.c:1665
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: 0033:0x7f3e4c4cf097
RSP: 002b:00007fff53f99e38 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3e4c5632ca RCX: 00007f3e4c4cf097
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff53f99ef0
RBP: 00007fff53f99ef0 R08: 00007fff53f9aef0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff53f9af80
R13: 00007f3e4c5632ca R14: 0000000000159565 R15: 00007fff53f9afc0
Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
#0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90000117c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90000117c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
1 lock held by kauditd/37:
#0: ffffffff8e219938 (kauditd_wait.lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#0: ffffffff8e219938 (kauditd_wait.lock){+.+.}-{3:3}, at: prepare_to_wait_event+0x20/0x470 kernel/sched/wait.c:294
1 lock held by khungtaskd/38:
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:9/1197:
2 locks held by kworker/u8:13/3307:
#0: ffff88801f2e5938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801f2e5938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc9000e447c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc9000e447c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
4 locks held by kworker/u8:18/3465:
2 locks held by getty/5360:
#0: ffff888032f210a0 (&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+0x460/0x1360 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/16496:
#0: ffff88803c9020d0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803c9020d0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88803c9020d0 (&type->s_umount_key#61){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
3 locks held by kworker/u8:2/17959:
#0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90004b77c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90004b77c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffffffff8f5b05f8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
4 locks held by syz-executor/18008:
#0: ffff888036fee500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#0: ffff888036fee500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
#1: ffff888061b0a878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
#2: ffff8880297a7788 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff8880297a7788 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
#3: ffffffff8ee260d8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184
4 locks held by udevd/18021:
9 locks held by syz-executor/18072:
3 locks held by syz-executor/18366:
#0: ffffffff8ecf4848 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ecf4848 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8ecf4848 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f5b05f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f5b05f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f5b05f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158
#2: ffff88813ff67238 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_add_one+0x41/0x5e0 fs/kernfs/dir.c:825
2 locks held by syz-executor/18451:
#0: ffffffff8f5a1a60 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4e2/0x720 net/core/net_namespace.c:575
#1: ffffffff8f5b05f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
#1: ffffffff8f5b05f8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x60 net/core/dev.c:11553
4 locks held by syz.3.1089/18493:
3 locks held by dhcpcd-run-hook/18496:
2 locks held by modprobe/18497:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3465 Comm: kworker/u8:18 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: bat_events batadv_dat_purge
RIP: 0010:match_held_lock+0x78/0xb0 kernel/locking/lockdep.c:5337
Code: 00 00 48 c7 c2 d0 f4 45 93 48 29 d0 48 c1 f8 03 48 ba 29 5c 8f c2 f5 28 5c 8f 48 0f af d0 bb 01 00 00 00 48 39 ca 74 02 31 db <89> d8 5b 41 5e c3 cc cc cc cc cc 90 e8 d7 1b 7d f9 85 c0 74 1c 83
RSP: 0018:ffffc9000e8379d0 EFLAGS: 00000046
RAX: 0000000000000005 RBX: 0000000000000001 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8e1c3000 RDI: ffff8880338b8ca8
RBP: ffff8880338b8ca8 R08: ffffffff8faf74f7 R09: 1ffffffff1f5ee9e
R10: dffffc0000000000 R11: fffffbfff1f5ee9f R12: 0000000000000004
R13: 0000000000000004 R14: ffffffff8e1c3000 R15: ffff8880338b8000
FS: 0000000000000000(0000) GS:ffff888125d4c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd45beeff8 CR3: 000000005a3a8000 CR4: 00000000003526f0
Call Trace:
find_held_lock kernel/locking/lockdep.c:5350 [inline]
__lock_release kernel/locking/lockdep.c:5535 [inline]
lock_release+0x10c/0x3c0 kernel/locking/lockdep.c:5889
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
rt_spin_unlock+0x163/0x200 kernel/locking/spinlock_rt.c:102
spin_unlock_bh include/linux/spinlock_rt.h:115 [inline]
__batadv_dat_purge+0x334/0x400 net/batman-adv/distributed-arp-table.c:186
batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:205
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
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