INFO: task kworker/u4:1:10001 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1    state:D stack:22544 pid:10001 ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 schedule+0xbd/0x170 kernel/sched/core.c:6773
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
 hfsplus_find_init+0x154/0x1d0 fs/hfsplus/bfind.c:28
 hfsplus_cat_write_inode+0x1e7/0x7b0 fs/hfsplus/inode.c:593
 write_inode fs/fs-writeback.c:1483 [inline]
 __writeback_single_inode+0x705/0xee0 fs/fs-writeback.c:1700
 writeback_sb_inodes+0x77c/0xef0 fs/fs-writeback.c:1926
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:1997
 wb_writeback+0x464/0xba0 fs/fs-writeback.c:2107
 wb_check_background_flush fs/fs-writeback.c:2177 [inline]
 wb_do_writeback fs/fs-writeback.c:2265 [inline]
 wb_workfn+0xb32/0xe20 fs/fs-writeback.c:2292
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/0:2/787:
 #0: 
ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #1: ffffc90003b07d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #1: ffffc90003b07d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #2: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/u4:6/1095:
 #0: ffff88802c4b9d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #0: ffff88802c4b9d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #1: 
ffffc9000469fd00
 (
(work_completion)(&(&ifa->dad_work)->work)
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #2: 
ffffffff8dfb5448
 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x14e0 net/ipv6/addrconf.c:4158
3 locks held by kworker/u4:9/1125:
 #0: 
ffff888017871538
 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #1: ffffc9000485fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #1: ffffc9000485fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #2: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
5 locks held by kworker/u4:12/4436:
 #0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #1: ffffc9000eb67d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #1: ffffc9000eb67d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #2: ffffffff8dfa8610 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x136/0xb90 net/core/net_namespace.c:606
 #3: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa60 net/core/dev.c:11606
 #4: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
 #4: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
2 locks held by dhcpcd/5434:
 #0: 
ffff88801beeb690
 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf4/0x810 net/netlink/af_netlink.c:2336
 #1: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x71f/0xde0 net/netlink/af_netlink.c:2263
2 locks held by getty/5535:
 #0: 
ffff8880314580a0
 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
4 locks held by kworker/u4:1/10001:
 #0: ffff88801a27f938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #0: ffff88801a27f938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #1: ffffc90004187d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #1: ffffc90004187d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #2: ffff888068d740e0 (&type->s_umount_key#98){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607
 #3: ffff88805e6700b0 (&tree->tree_lock#2){+.+.}-{3:3}, at: hfsplus_find_init+0x154/0x1d0 fs/hfsplus/bfind.c:28
8 locks held by syz.0.832/11598:
2 locks held by syz.2.916/12249:
 #0: 
ffff888068d740e0 (&type->s_umount_key#98){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline]
ffff888068d740e0 (&type->s_umount_key#98){++++}-{3:3}, at: super_lock+0x167/0x360 fs/super.c:117
 #1: ffff8880215787d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline]
 #1: ffff8880215787d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a0/0x9e0 fs/fs-writeback.c:2770
1 lock held by syz-executor/12487:
 #0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
 #0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469
7 locks held by syz-executor/12580:
 #0: ffff888031788418
 (
sb_writers
#8
){.+.+}-{0:0}
, at: vfs_write+0x20e/0x940 fs/read_write.c:580
 #1: 
ffff8880413a0488
 (
&of->mutex
){+.+.}-{3:3}
, at: kernfs_fop_write_iter+0x1e7/0x520 fs/kernfs/file.c:343
 #2: ffff8880246aa1f8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff8880246aa1f8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x23a/0x520 fs/kernfs/file.c:344
 #3: ffffffff8d8984a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd2/0x360 drivers/net/netdevsim/bus.c:209
 #4: 
ffff8880419560e8
 (
&dev->mutex
){....}-{3:3}
, at: device_lock include/linux/device.h:995 [inline]
, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
, at: device_release_driver_internal+0xb6/0x7a0 drivers/base/dd.c:1292
 #5: 
ffff888041957250
 (
&devlink->lock_key
#17
){+.+.}-{3:3}
, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675
 #6: 
ffffffff8dfb5448
 (
rtnl_mutex
){+.+.}-{3:3}, at: nsim_destroy+0x3f/0x180 drivers/net/netdevsim/netdev.c:417
2 locks held by syz.6.952/12839:
 #0: 
ffff888059cb6690
 (
nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf4/0x810 net/netlink/af_netlink.c:2336
 #1: 
ffffffff8dfb5448
 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x71f/0xde0 net/netlink/af_netlink.c:2263

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf41/0xf80 kernel/hung_task.c:379
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11598 Comm: syz.0.832 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:kasan_check_range+0x1bd/0x290 mm/kasan/generic.c:-1
Code: 4d 01 f3 49 8d 5c 24 07 4d 85 e4 49 0f 49 dc 48 83 e3 f8 49 29 dc 74 12 41 80 3b 00 0f 85 a6 00 00 00 49 ff c3 49 ff cc 75 ee <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 45 84 ff 75 61 41 f7 c7 00 ff 00
RSP: 0018:ffffc90004da68f8 EFLAGS: 00000256
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8a582d42
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8aab7e45
RBP: ffffffff8aab7e46 R08: ffffffff8aab7e45 R09: 1ffffffff1556fc8
R10: dffffc0000000000 R11: fffffbfff1556fc9 R12: 0000000000000001
R13: ffffc90004da6c26 R14: fffffbfff1556fc9 R15: 1ffffffff1556fc8
FS:  00007f57eac2f6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005598b5a28088 CR3: 000000005ee61000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 vsnprintf+0x7b2/0x1a40 lib/vsprintf.c:2785
 sprintf+0xda/0x120 lib/vsprintf.c:3027
 print_time kernel/printk/printk.c:1327 [inline]
 info_print_prefix+0x156/0x300 kernel/printk/printk.c:1353
 record_print_text+0x155/0x420 kernel/printk/printk.c:1402
 printk_get_next_message+0x282/0x8e0 kernel/printk/printk.c:2876
 console_emit_next_record kernel/printk/printk.c:2911 [inline]
 console_flush_all+0x3ad/0xd00 kernel/printk/printk.c:3000
 console_unlock+0xae/0x340 kernel/printk/printk.c:3069
 vprintk_emit+0x477/0x600 kernel/printk/printk.c:2341
 _printk+0xd0/0x110 kernel/printk/printk.c:2366
 hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:60 [inline]
 hfsplus_bnode_dump+0x321/0x440 fs/hfsplus/bnode.c:362
 hfsplus_brec_remove+0x47a/0x550 fs/hfsplus/brec.c:229
 __hfsplus_delete_attr+0x1d5/0x360 fs/hfsplus/attributes.c:299
 hfsplus_delete_attr+0x232/0x2d0 fs/hfsplus/attributes.c:345
 hfsplus_removexattr fs/hfsplus/xattr.c:798 [inline]
 __hfsplus_setxattr+0x74b/0x1f00 fs/hfsplus/xattr.c:279
 hfsplus_setxattr+0x11e/0x170 fs/hfsplus/xattr.c:438
 hfsplus_user_setxattr+0x40/0x50 fs/hfsplus/xattr_user.c:30
 __vfs_removexattr+0x425/0x460 fs/xattr.c:519
 __vfs_removexattr_locked+0x1e8/0x230 fs/xattr.c:554
 vfs_removexattr+0x81/0x1b0 fs/xattr.c:576
 removexattr fs/xattr.c:908 [inline]
 path_removexattr+0x204/0x3f0 fs/xattr.c:929
 __do_sys_removexattr fs/xattr.c:943 [inline]
 __se_sys_removexattr fs/xattr.c:940 [inline]
 __x64_sys_removexattr+0x60/0x70 fs/xattr.c:940
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f57e9d8f749
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:00007f57eac2f038 EFLAGS: 00000246 ORIG_RAX: 00000000000000c5
RAX: ffffffffffffffda RBX: 00007f57e9fe5fa0 RCX: 00007f57e9d8f749
RDX: 0000000000000000 RSI: 0000200000000080 RDI: 0000200000000040
RBP: 00007f57e9e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f57e9fe6038 R14: 00007f57e9fe5fa0 R15: 00007ffe871de768
 </TASK>