INFO: task kworker/u8:5:70 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5 state:D stack:21504 pid:70 tgid:70 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:8)
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
io_schedule+0x80/0xe0 kernel/sched/core.c:7835
TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline]
txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:375
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/0x11a0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x995/0x19d0 fs/fs-writeback.c:2054
wb_writeback+0x456/0xb70 fs/fs-writeback.c:2239
wb_do_writeback fs/fs-writeback.c:2386 [inline]
wb_workfn+0x41a/0xf60 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
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
INFO: task syz-executor:7549 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:22688 pid:7549 tgid:7549 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
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:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb425a2da57
RSP: 002b:00007ffd6c49b248 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fb425ac2048 RCX: 00007fb425a2da57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd6c49b300
RBP: 00007ffd6c49b300 R08: 00007ffd6c49c300 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6c49c390
R13: 00007fb425ac2048 R14: 00000000000404f5 R15: 00007ffd6c49c3d0
Showing all locks held in the system:
5 locks held by kworker/0:0/9:
3 locks held by kworker/u8:0/12:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90000117c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90000117c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffffffff8f15d4b8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
4 locks held by kworker/1:0/31:
1 lock held by khungtaskd/37:
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/68:
#0: ffff88803130f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88803130f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc9000153fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc9000153fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffffffff8f15d4b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f15d4b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4198
2 locks held by kworker/u8:5/70:
#0: ffff88801aac4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88801aac4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc9000155fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc9000155fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
2 locks held by getty/5555:
#0: ffff88803634f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:2/5800:
#0: ffff888062b6a138 ((wq_completion)hci0#3){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff888062b6a138 ((wq_completion)hci0#3){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900046d7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900046d7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff88805ef68f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331
1 lock held by syz-executor/7549:
#0: ffff888061fd80d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888061fd80d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888061fd80d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
3 locks held by syz-executor/7600:
3 locks held by udevd/9616:
1 lock held by syz-executor/9690:
#0: ffffffff8f15d4b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f15d4b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f15d4b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107
1 lock held by syz.7.520/9912:
#0: ffff888061fd80d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888061fd80d0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz-executor/10102:
1 lock held by udevadm/10165:
#0: ffff888019c4f238 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x9e/0x5e0 fs/kernfs/dir.c:1185
2 locks held by udevadm/10185:
2 locks held by syz.4.548/10189:
5 locks held by dhcpcd-run-hook/10190:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
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: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:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
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: 10190 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:check_preemption_disabled+0x1/0xe0 lib/smp_processor_id.c:13
Code: 20 7a a6 8b 48 c7 c6 60 7a a6 8b 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 47 73 2a 07 65 8b 0d 3c 73 2a 07 f7 c1 ff
RSP: 0018:ffffc900048374a8 EFLAGS: 00000046
RAX: 0000000080000000 RBX: ffffffff8b27d48a RCX: 0000000000014558
RDX: 000000005b88b86b RSI: ffffffff8d5c7a32 RDI: ffffffff8ba67a80
RBP: 000000000021a310 R08: 00000000bae66249 R09: 000000000a76add7
R10: 000000000000000e R11: ffffffff81af8e10 R12: ffffffff998a6378
R13: 0000000000000000 R14: ffffffff998a6380 R15: ffffffff8b4e1ba0
FS: 0000000000000000(0000) GS:ffff888126432000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005583c1bf8950 CR3: 000000003c1b8000 CR4: 00000000003526f0
Call Trace:
lockdep_hardirqs_off+0x8d/0xd0 kernel/locking/lockdep.c:4495
trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:104
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline]
_raw_spin_lock_irqsave+0x1a/0x60 kernel/locking/spinlock.c:162
debug_object_activate+0x72/0x520 lib/debugobjects.c:835
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_rcu_common kernel/rcu/tree.c:3116 [inline]
call_rcu+0x43/0x890 kernel/rcu/tree.c:3251
slab_free_hook mm/slub.c:2649 [inline]
slab_free mm/slub.c:6165 [inline]
kmem_cache_free+0x50e/0x6b0 mm/slub.c:6295
tear_down_vmas+0x312/0x520 mm/mmap.c:1264
exit_mmap+0x4b6/0xa10 mm/mmap.c:1322
__mmput+0xcb/0x3d0 kernel/fork.c:1175
exec_mmap+0x3b2/0x440 fs/exec.c:893
begin_new_exec+0x1350/0x24b0 fs/exec.c:1148
load_elf_binary+0xa50/0x29b0 fs/binfmt_elf.c:1011
search_binary_handler fs/exec.c:1664 [inline]
exec_binprm fs/exec.c:1696 [inline]
bprm_execve+0x93d/0x1460 fs/exec.c:1748
do_execveat_common+0x50d/0x690 fs/exec.c:1846
__do_sys_execve fs/exec.c:1930 [inline]
__se_sys_execve fs/exec.c:1924 [inline]
__x64_sys_execve+0x97/0xc0 fs/exec.c:1924
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: 0033:0x7fd7976bc107
Code: Unable to access opcode bytes at 0x7fd7976bc0dd.
RSP: 002b:00007fff50e1ad48 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00005583c1c09078 RCX: 00007fd7976bc107
RDX: 00005583c1c090a0 RSI: 00005583c1c09078 RDI: 00005583c1c09130
RBP: 00005583c1c09130 R08: 00007fff50e1fe4e R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 00005583c1c090a0
R13: 00007fd797881e8b R14: 00005583c1c090a0 R15: 0000000000000000