INFO: task kworker/u4:14:4414 blocked for more than 143 seconds. Not tainted 5.15.169-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:14 state:D stack: 0 pid: 4414 ppid: 2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-7:3) Call trace: __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518 context_switch kernel/sched/core.c:5027 [inline] __schedule+0xf10/0x1e48 kernel/sched/core.c:6373 schedule+0x11c/0x1c8 kernel/sched/core.c:6456 rwsem_down_write_slowpath+0xd94/0x17e0 kernel/locking/rwsem.c:1165 __down_write_common kernel/locking/rwsem.c:1292 [inline] __down_write kernel/locking/rwsem.c:1301 [inline] down_write+0xe8/0x12c kernel/locking/rwsem.c:1552 f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528 f2fs_write_inode+0x42c/0x4a0 fs/f2fs/inode.c:736 write_inode fs/fs-writeback.c:1495 [inline] __writeback_single_inode+0x584/0x13a4 fs/fs-writeback.c:1705 writeback_sb_inodes+0x94c/0x1654 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x110/0x39c fs/fs-writeback.c:2001 wb_writeback+0x410/0xfc8 fs/fs-writeback.c:2106 wb_check_background_flush fs/fs-writeback.c:2172 [inline] wb_do_writeback fs/fs-writeback.c:2260 [inline] wb_workfn+0xc44/0x1070 fs/fs-writeback.c:2288 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffff800014c822e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311 3 locks held by kworker/u4:2/148: 5 locks held by kworker/0:2/3322: #0: ffff0000c28d9d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff8000209e7c00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000cf2d1220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff0000cf2d1220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1b8/0x46b8 drivers/usb/core/hub.c:5769 #3: ffff0000ce30c220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff0000ce30c220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x90/0x480 drivers/base/dd.c:954 #4: ffff0000cf2d3098 (&hub->status_mutex){+.+.}-{3:3}, at: hub_ext_port_status+0x74/0x614 drivers/usb/core/hub.c:606 2 locks held by udevd/3645: 2 locks held by getty/3784: #0: ffff0000d38a5098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340 #1: ffff80001d5ee2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158 2 locks held by kworker/u4:11/4215: #0: ffff0000c0029138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff8000206b7c00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 4 locks held by kworker/u4:14/4414: #0: ffff0000c0dac938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff8000204b7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 #2: ffff0000ea5040e0 (&type->s_umount_key#61){++++}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:418 #3: ffff0000d909d1b0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x3e8/0x6a0 fs/f2fs/segment.c:528 5 locks held by syz.3.99/4449: 2 locks held by kworker/0:9/5157: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 #1: ffff800020827c00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285 2 locks held by syz.2.714/6643: #0: ffff0000cbf3a918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912 #1: ffff0000cbf85468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x58/0x210 drivers/block/loop.c:2070 =============================================