INFO: task kworker/u8:2:43 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:20904 pid:43    tgid:43    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x16ec/0x5620 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7564
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1662 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1739 [inline]
 __rt_mutex_slowlock_locked+0x1f28/0x2550 kernel/locking/rtmutex.c:1779
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1819
 __rt_mutex_lock kernel/locking/rtmutex.c:1834 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:245
 f2fs_down_write fs/f2fs/f2fs.h:2411 [inline]
 f2fs_down_write_trace fs/f2fs/checkpoint.c:180 [inline]
 f2fs_issue_checkpoint+0x437/0x790 fs/f2fs/checkpoint.c:2095
 f2fs_balance_fs_bg+0x574/0x9d0 fs/f2fs/segment.c:545
 f2fs_write_node_pages+0x158/0x700 fs/f2fs/node.c:2257
 do_writepages+0x32e/0x550 mm/page-writeback.c:2571
 __writeback_single_inode+0x133/0x10e0 fs/fs-writeback.c:1764
 writeback_sb_inodes+0x97f/0x1980 fs/fs-writeback.c:2056
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2132
 wb_writeback+0x459/0xb00 fs/fs-writeback.c:2243
 wb_check_old_data_flush fs/fs-writeback.c:2347 [inline]
 wb_do_writeback fs/fs-writeback.c:2400 [inline]
 wb_workfn+0xb17/0xf20 fs/fs-writeback.c:2428
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 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
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
4 locks held by pr/legacy/17:
3 locks held by rcuc/0/20:
1 lock held by khungtaskd/38:
 #0: ffffffff8dfc8080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8dfc8080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8dfc8080 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/43:
 #0: ffff88801f2af938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801f2af938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90000b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90000b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffff88803dc880d0 (&type->s_umount_key#72){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
 #3: ffff888059805a98 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2411 [inline]
 #3: ffff888059805a98 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write_trace fs/f2fs/checkpoint.c:180 [inline]
 #3: ffff888059805a98 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_issue_checkpoint+0x437/0x790 fs/f2fs/checkpoint.c:2095
3 locks held by kworker/u8:8/1170:
 #0: ffff88801a074138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a074138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90006497c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90006497c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
3 locks held by kworker/u8:9/1180:
 #0: ffff888032034138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff888032034138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90006567c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90006567c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206
2 locks held by dhcpcd/5256:
 #0: ffff88803b508928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404
 #1: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6864
2 locks held by getty/5350:
 #0: ffff888036d230a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:4/5702:
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc90004ecfc40 (rx_mode_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc90004ecfc40 (rx_mode_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_rx_mode_work+0x1c/0x450 net/core/dev_addr_lists.c:1312
3 locks held by kworker/1:6/9722:
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88801a037938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc900030dfc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc900030dfc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by syz-executor/10659:
 #0: ffff888064306480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
5 locks held by syz.5.728/12752:
1 lock held by syz-executor/14615:
 #0: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5039
4 locks held by syz-executor/14792:
 #0: ffff888036c9c480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline]
 #0: ffff888036c9c480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
 #1: ffff888063731878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
 #2: ffff888028b103c8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888028b103c8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
 #3: ffffffff8ebd04b8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184
7 locks held by syz-executor/14947:
 #0: ffff888036c9c480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline]
 #0: ffff888036c9c480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
 #1: ffff888062b06078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
 #2: ffff888028b102d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888028b102d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
 #3: ffffffff8ebd04b8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234
 #4: ffff88803610d160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
 #4: ffff88803610d160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline]
 #4: ffff88803610d160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870 drivers/base/dd.c:1372
 #5: ffff888033da0310 (&devlink->lock_key#29){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1799
 #6: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #6: ffffffff8f3584f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2162
2 locks held by syz.3.976/15275:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 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: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+0xfd3/0x1030 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5812 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:stack_trace_consume_entry+0xb/0x280 kernel/stacktrace.c:83
Code: e8 ba ae 6d 09 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 f3 0f 1e fa 55 41 57 41 56 41 55 <41> 54 53 48 83 ec 18 48 ba 00 00 00 00 00 fc ff df 4c 8d 47 10 4c
RSP: 0018:ffffc9000529f100 EFLAGS: 00000282
RAX: ffffffff82377620 RBX: ffffc9000529f1e0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff82377620 RDI: ffffc9000529f1e0
RBP: ffffc9000529f1b0 R08: ffffc9000529f818 R09: 0000000000000000
R10: ffffc9000529f178 R11: ffffffff81af9560 R12: ffff888028a85c40
R13: ffff888054932000 R14: ffffffff81af9560 R15: ffffc9000529f128
FS:  00007f00ad2b2880(0000) GS:ffff888126171000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fae8d195000 CR3: 000000002af52000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_stack_walk+0x10f/0x150 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5295 [inline]
 __kmalloc_noprof+0x3e7/0x7b0 mm/slub.c:5307
 kmalloc_noprof include/linux/slab.h:954 [inline]
 tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776
 security_file_open+0xa9/0x240 security/security.c:2739
 do_dentry_open+0x4c0/0x13e0 fs/open.c:924
 vfs_open+0x3b/0x350 fs/open.c:1079
 do_open fs/namei.c:4699 [inline]
 path_openat+0x2e43/0x38a0 fs/namei.c:4858
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f00ad3a0407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff44f68730 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f00ad2b2880 RCX: 00007f00ad3a0407
RDX: 00000000000a0800 RSI: 00005580808f8280 RDI: ffffffffffffff9c
RBP: 00005580808f7910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005580809e0020
R13: 0000558080905190 R14: 0000000000000000 R15: 00005580809e0020
 </TASK>