INFO: task kworker/u8:4:62 blocked for more than 143 seconds.
      Not tainted 6.12.0-rc3-syzkaller-00007-g6485cf5ea253 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:20024 pid:62    tgid:62    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0x1843/0x4ae0 kernel/sched/core.c:6682
 __schedule_loop kernel/sched/core.c:6759 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6774
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
 exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108
 write_inode fs/fs-writeback.c:1503 [inline]
 __writeback_single_inode+0x711/0x10d0 fs/fs-writeback.c:1723
 writeback_sb_inodes+0x80c/0x1370 fs/fs-writeback.c:1954
 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2025
 wb_writeback+0x42f/0xbd0 fs/fs-writeback.c:2136
 wb_check_background_flush fs/fs-writeback.c:2206 [inline]
 wb_do_writeback fs/fs-writeback.c:2294 [inline]
 wb_workfn+0xc58/0x1090 fs/fs-writeback.c:2321
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
 #0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 #0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976
1 lock held by khungtaskd/30:
 #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
4 locks held by kworker/u8:4/62:
 #0: ffff888020694948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff888020694948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc900015d7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc900015d7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
 #2: ffff888069aee0e0 (&type->s_umount_key#61){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
 #3: ffff88807d5240e8 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108
3 locks held by kworker/u8:8/2943:
 #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc90009dbfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc90009dbfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
 #2: ffffffff8fcb34d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580
2 locks held by getty/4975:
 #0: ffff88802fe200a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/6141:
4 locks held by syz-executor/8058:
 #0: ffff888033a56420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline]
 #0: ffff888033a56420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679
 #1: ffff888027abe488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325
 #2: ffff888143bd9b48 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326
 #3: ffffffff8f55e0a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
6 locks held by syz-executor/8063:
 #0: ffff888033a56420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline]
 #0: ffff888033a56420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679
 #1: ffff88802840a488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325
 #2: ffff888143bd9b48 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326
 #3: ffffffff8f55e0a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
 #4: ffff88807d0d10e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
 #4: ffff88807d0d10e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
 #4: ffff88807d0d10e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293
 #5: ffff8880606ea250 (&devlink->lock_key#25){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672
1 lock held by syz.1.250/8073:
1 lock held by syz.1.250/8080:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1748
1 lock held by syz.1.250/8081:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1748
1 lock held by syz.1.250/8082:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: open_last_lookups fs/namei.c:3691 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: path_openat+0x89a/0x3590 fs/namei.c:3930
1 lock held by syz.1.250/8083:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23/1){+.+.}-{3:3}, at: filename_create+0x260/0x540 fs/namei.c:4026
1 lock held by syz.1.250/8084:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1748
1 lock held by syz.1.250/8099:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: open_last_lookups fs/namei.c:3693 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: path_openat+0x88b/0x3590 fs/namei.c:3930
1 lock held by syz.1.250/8100:
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:825 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: open_last_lookups fs/namei.c:3693 [inline]
 #0: ffff88805adc0180 (&type->i_mutex_dir_key#23){++++}-{3:3}, at: path_openat+0x88b/0x3590 fs/namei.c:3930
2 locks held by syz-executor/8221:
 #0: ffffffff8fcb34d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490
 #1: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 #1: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976
1 lock held by dhcpcd/8242:
 #0: ffff888066a5e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1611 [inline]
 #0: ffff888066a5e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3266

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00007-g6485cf5ea253 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8073 Comm: syz.1.250 Not tainted 6.12.0-rc3-syzkaller-00007-g6485cf5ea253 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5563 [inline]
RIP: 0010:lock_is_held_type+0x82/0x190 kernel/locking/lockdep.c:5897
Code: 41 89 f6 49 89 ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 4c 8b 24 24 fa 48 c7 c7 a0 d7 0a 8c e8 65 1b 00 00 65 ff 05 9e 5f 45 74 <41> 83 bd d8 0a 00 00 00 7e 47 4c 89 eb 48 81 c3 e0 0a 00 00 31 ed
RSP: 0018:ffffc900047f6f38 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 00000000ffffffff RCX: ffff88802cda8000
RDX: ffff88802cda8000 RSI: ffffffff8c0ad7a0 RDI: ffffffff8c6028a0
RBP: dffffc0000000000 R08: ffffffff8bb81ff7 R09: 1ffffffff2852500
R10: dffffc0000000000 R11: fffffbfff2852501 R12: 0000000000000246
R13: ffff88802cda8000 R14: 00000000ffffffff R15: ffff888148c95918
FS:  00007fc84aa966c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005600fe55e131 CR3: 000000005ecd6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_is_held include/linux/lockdep.h:249 [inline]
 xa_entry include/linux/xarray.h:1220 [inline]
 xas_descend lib/xarray.c:207 [inline]
 xas_load+0x19c/0x5c0 lib/xarray.c:245
 filemap_get_entry+0x1f0/0x3b0 mm/filemap.c:1842
 __filemap_get_folio+0x71/0xbd0 mm/filemap.c:1887
 __find_get_block_slow fs/buffer.c:203 [inline]
 __find_get_block+0x28a/0x1150 fs/buffer.c:1404
 bdev_getblk+0x33/0x550 fs/buffer.c:1431
 __bread_gfp+0x86/0x400 fs/buffer.c:1491
 sb_bread include/linux/buffer_head.h:346 [inline]
 get_branch+0x2c3/0x6e0 fs/sysv/itree.c:102
 get_block+0x180/0x16d0 fs/sysv/itree.c:222
 block_read_full_folio+0x418/0xcd0 fs/buffer.c:2401
 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367
 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3825
 read_mapping_folio include/linux/pagemap.h:1011 [inline]
 dir_get_folio fs/sysv/dir.c:64 [inline]
 sysv_find_entry+0x16a/0x4b0 fs/sysv/dir.c:154
 sysv_inode_by_name+0x98/0x2a0 fs/sysv/dir.c:370
 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38
 __lookup_slow+0x28c/0x3f0 fs/namei.c:1732
 lookup_slow+0x53/0x70 fs/namei.c:1749
 walk_component+0x2e1/0x410 fs/namei.c:2053
 lookup_last fs/namei.c:2556 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2580
 filename_lookup+0x256/0x610 fs/namei.c:2609
 user_path_at+0x3a/0x60 fs/namei.c:3016
 __do_sys_chdir fs/open.c:561 [inline]
 __se_sys_chdir+0xbc/0x220 fs/open.c:555
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc849d7dff9
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:00007fc84aa96038 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
RAX: ffffffffffffffda RBX: 00007fc849f35f80 RCX: 00007fc849d7dff9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200001c0
RBP: 00007fc849df0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc849f35f80 R15: 00007ffe31114c18
 </TASK>