INFO: task kworker/u8:7:928 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:7    state:D stack:0     pid:928   tgid:928   ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue: writeback wb_workfn (flush-7:2)
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7083
 rwsem_down_write_slowpath+0x6b4/0x10f4 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0xb4/0xc0 kernel/locking/rwsem.c:1591
 f2fs_down_write fs/f2fs/f2fs.h:2294 [inline]
 f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464
 f2fs_write_inode+0x3a8/0x684 fs/f2fs/inode.c:820
 write_inode fs/fs-writeback.c:1564 [inline]
 __writeback_single_inode+0x5ac/0x13e8 fs/fs-writeback.c:1784
 writeback_sb_inodes+0x55c/0xe40 fs/fs-writeback.c:2015
 __writeback_inodes_wb+0xec/0x228 fs/fs-writeback.c:2086
 wb_writeback+0x3e0/0xd70 fs/fs-writeback.c:2197
 wb_check_old_data_flush fs/fs-writeback.c:2301 [inline]
 wb_do_writeback fs/fs-writeback.c:2354 [inline]
 wb_workfn+0xa08/0xdc0 fs/fs-writeback.c:2382
 process_one_work+0x7e8/0x155c kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3427
 kthread+0x5fc/0x75c kernel/kthread.c:463
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844

Showing all locks held in the system:
3 locks held by kworker/u8:1/15:
 #0: ffff0000d2ddb948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff800097ab7be0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff800092888228 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
3 locks held by kworker/1:0/24:
 #0: ffff0000c0029948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff800097b57be0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff0000d89f9240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x188/0x308 drivers/net/netdevsim/fib.c:1490
1 lock held by khungtaskd/32:
 #0: ffff80008f79b760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
4 locks held by kworker/u8:2/41:
 #0: ffff0000c1843148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff8000990e7be0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff80009287b3f0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x6dc net/core/net_namespace.c:669
 #3: ffff800092888228 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
2 locks held by pr/ttyAMA-1/43:
4 locks held by kworker/u8:7/928:
 #0: ffff0000c1c69148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff80009c817be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff0000f9ac80e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:562
 #3: ffff0000d4515478 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2294 [inline]
 #3: ffff0000d4515478 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464
3 locks held by kworker/1:3/2322:
 #0: ffff0000c0029948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff8000a13b7be0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff800092888228 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
2 locks held by getty/6337:
 #0: ffff0000d35440a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009bb5b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/6561:
2 locks held by syz.2.69/7008:
 #0: ffff0000f9ac8420 (sb_writers#19){.+.+}-{0:0}, at: direct_splice_actor+0x54/0x14c fs/splice.c:1160
 #1: ffff0000d4515478 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2294 [inline]
 #1: ffff0000d4515478 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464
1 lock held by syz-executor/8458:
 #0: ffff800092888228 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
1 lock held by syz-executor/8582:
2 locks held by syz-executor/8657:

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