INFO: task kworker/u8:9:2970 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:9 state:D stack:24384 pid:2970 tgid:2970 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
context_switch kernel/sched/core.c:5290 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6902
__schedule_loop kernel/sched/core.c:6984 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6999
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7056
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7ca/0x1300 kernel/locking/mutex.c:776
hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
hfsplus_cat_write_inode+0x1e6/0x7a0 fs/hfsplus/inode.c:625
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75a/0x1070 fs/fs-writeback.c:1813
writeback_sb_inodes+0x93a/0x1870 fs/fs-writeback.c:2041
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2118
wb_writeback+0x43f/0xaa0 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+0xad2/0xed0 fs/fs-writeback.c:2414
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 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:
#0: ffffffff8dfeb328 (wq_pool_mutex){+.+.}-{4:4}, at: pwq_release_workfn+0x3e5/0x880 kernel/workqueue.c:5181
1 lock held by khungtaskd/30:
#0: ffffffff8e144ce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e144ce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e144ce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:9/2970:
#0: ffff88801f6c9948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc9000b75fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
#2: ffff888021fee0e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff8880268360b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
1 lock held by udevd/5195:
2 locks held by getty/5581:
#0: ffff8880344ed0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
2 locks held by kworker/u8:21/6038:
#0: ffff88813fe29148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
#1: ffffc90004f77c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
4 locks held by syz.0.113/6548:
1 lock held by syz-executor/7041:
2 locks held by udevd/7178:
6 locks held by syz.6.260/8065:
#0: ffffffff8e14a2f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8e14a2f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:961
#1: ffff8880b863abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
#2: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#3: ffff88807c7e0d48 (&new_ns->poll){....}-{3:3}, at: __wake_up_common_lock+0x2f/0x1f0 kernel/sched/wait.c:124
#4: ffffffff8e138b80 (console_owner){-.-.}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:317 [inline]
#4: ffffffff8e138b80 (console_owner){-.-.}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
#4: ffffffff8e138b80 (console_owner){-.-.}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
#4: ffffffff8e138b80 (console_owner){-.-.}-{0:0}, at: console_flush_one_record kernel/printk/printk.c:3194 [inline]
#4: ffffffff8e138b80 (console_owner){-.-.}-{0:0}, at: console_flush_all+0x11a/0xb00 kernel/printk/printk.c:3291
#5: ffffffff8e138b38 (console_owner_lock){-.-.}-{2:2}, at: console_lock_spinning_disable_and_check+0x35/0x100 kernel/printk/printk.c:1941
2 locks held by udevd/8070:
3 locks held by syz.5.262/8092:
1 lock held by modprobe/8099:
1 lock held by dhcpcd-run-hook/8106:
4 locks held by udevd/8108:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 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: 6548 Comm: syz.0.113 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_preemption_disabled+0x5/0xe0 lib/smp_processor_id.c:13
Code: 48 c7 c6 40 97 e0 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 87 b3 43 07 65 8b 0d 7c b3 43 07 f7 c1 ff ff ff 7f 74
RSP: 0018:ffffc9000baeead0 EFLAGS: 00000002
RAX: 0000000000000003 RBX: 0000000000000899 RCX: ffffffff99adc403
RDX: 0000000000000898 RSI: ffffffff8be09740 RDI: ffffffff8be09700
RBP: ffffffff99e31450 R08: ffff888022768237 R09: 1ffff110044ed046
R10: dffffc0000000000 R11: ffffffff8b5d43f0 R12: 1ffffffff33c628a
R13: 00000000ffffffff R14: dffffc0000000000 R15: 0000000000000819
FS: 00007fd595ff66c0(0000) GS:ffff888125cf9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f68879212c0 CR3: 000000002fff6000 CR4: 00000000003526f0
Call Trace:
delay_tsc+0x1c/0xc0 arch/x86/lib/delay.c:69
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0x160/0x2f0 drivers/tty/serial/8250/8250_port.c:1967
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x1301/0x1b60 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3131 [inline]
console_flush_one_record kernel/printk/printk.c:3217 [inline]
console_flush_all+0x713/0xb00 kernel/printk/printk.c:3291
__console_flush_and_unlock kernel/printk/printk.c:3321 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3361
vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2428
_printk+0xcf/0x120 kernel/printk/printk.c:2453
hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:60 [inline]
hfsplus_bnode_dump+0x16b/0xa00 fs/hfsplus/bnode.c:362
hfsplus_brec_remove+0x61c/0x700 fs/hfsplus/brec.c:229
__hfsplus_delete_attr+0x1d4/0x360 fs/hfsplus/attributes.c:299
hfsplus_delete_attr+0x239/0x3b0 fs/hfsplus/attributes.c:345
__hfsplus_setxattr+0x396/0x2170 fs/hfsplus/xattr.c:344
hfsplus_setxattr+0x11e/0x180 fs/hfsplus/xattr.c:434
hfsplus_trusted_setxattr+0x40/0x60 fs/hfsplus/xattr_trusted.c:30
__vfs_setxattr+0x43c/0x480 fs/xattr.c:200
__vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234
vfs_setxattr+0x162/0x360 fs/xattr.c:321
do_setxattr fs/xattr.c:636 [inline]
filename_setxattr+0x286/0x610 fs/xattr.c:664
path_setxattrat+0x364/0x3a0 fs/xattr.c:708
__do_sys_lsetxattr fs/xattr.c:749 [inline]
__se_sys_lsetxattr fs/xattr.c:745 [inline]
__x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:745
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd597d8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd595ff6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007fd597fe6090 RCX: 00007fd597d8f749
RDX: 00002000000001c0 RSI: 0000200000000180 RDI: 00002000000001c0
RBP: 00007fd597e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000361 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd597fe6128 R14: 00007fd597fe6090 R15: 00007ffcd745b518