INFO: task kworker/u8:0:12 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:21944 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 hfsplus_cat_write_inode+0x23e/0x810 fs/hfsplus/inode.c:625 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x7e1/0x1230 fs/fs-writeback.c:1802 writeback_sb_inodes+0x92e/0x1940 fs/fs-writeback.c:2030 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2107 wb_writeback+0x459/0xad0 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+0xaee/0xef0 fs/fs-writeback.c:2403 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 4 locks held by kworker/u8:0/12: #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90000117bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000117bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff8880283fe0e0 ( &type->s_umount_key #51){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88807ab040b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 1 lock held by khungtaskd/32: #0: ffffffff8e55a360 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:867 [inline] , at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:2/37: #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90000ad7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000ad7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff88803357e0e0 (&type->s_umount_key#51){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff8880308f80b0 ( &tree->tree_lock ){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 4 locks held by kworker/u8:3/50: #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90000bb7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000bb7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff8880330820e0 (&type->s_umount_key#51){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff888032d880b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 4 locks held by kworker/u8:4/60: #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000211fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000211fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff88801f7f40e0 (&type->s_umount_key#51){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff8880203500b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 4 locks held by kworker/u8:6/1132: #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff8881416e4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000391fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000391fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff88807ca700e0 (&type->s_umount_key#51){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff888079ea20b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 2 locks held by getty/5575: #0: ffff88814df880a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 7 locks held by syz.0.15/6418: 12 locks held by syz.1.16/6458: 7 locks held by syz.2.17/6489: