INFO: task kworker/u8:14:3572 blocked for more than 143 seconds. Workqueue: writeback wb_workfn (flush-7:1) writeback_sb_inodes+0x73c/0x16b4 fs/fs-writeback.c:2030 __writeback_inodes_wb+0xec/0x228 fs/fs-writeback.c:2107 wb_writeback+0x3c8/0xd70 fs/fs-writeback.c:2218 wb_check_old_data_flush fs/fs-writeback.c:2322 [inline] wb_do_writeback fs/fs-writeback.c:2375 [inline] wb_workfn+0xa08/0xdc0 fs/fs-writeback.c:2403 process_one_work+0x7c0/0x1558 kernel/workqueue.c:3257 Not tainted syzkaller #0 Call trace: __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 process_one_work+0x7c0/0x1558 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3421 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 1 lock held by khungtaskd/32: 4 locks held by kworker/u8:2/41: 4 locks held by kworker/u8:3/42: 2 locks held by pr/ttyAMA-1/43: #2: ffff0000d49500e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #2: ffff0000cb9880e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 4 locks held by kworker/u8:20/6003: #3: ffff0000e0531510 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2313 [inline] #3: ffff0000e0531510 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4c0/0x6d8 fs/f2fs/segment.c:464 #0: ffff0000d535d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #0: ffff0000c1ff2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231 #1: ffff80009ee57be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231