INFO: task kworker/u4:4:416 blocked for more than 143 seconds. Not tainted 6.1.94-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:0 pid:416 ppid:2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-7:2) Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:553 context_switch kernel/sched/core.c:5245 [inline] __schedule+0xee4/0x1c98 kernel/sched/core.c:6558 schedule+0xc4/0x170 kernel/sched/core.c:6634 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6693 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 jfs_commit_inode+0x1d4/0x4f8 fs/jfs/inode.c:102 jfs_write_inode+0x128/0x200 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x614/0x1770 fs/fs-writeback.c:1677 writeback_sb_inodes+0x978/0x1718 fs/fs-writeback.c:1903 __writeback_inodes_wb+0x110/0x39c fs/fs-writeback.c:1974 wb_writeback+0x428/0x1130 fs/fs-writeback.c:2079 wb_check_background_flush fs/fs-writeback.c:2145 [inline] wb_do_writeback fs/fs-writeback.c:2233 [inline] wb_workfn+0xc98/0x1034 fs/fs-writeback.c:2260 process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292 worker_thread+0x8e4/0xfec kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffff800015a24e70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffff800015a25670 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffff800015a24ca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349 4 locks held by kworker/u4:2/39: #0: ffff0000c40be938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265 #1: ffff80001b2c7c20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267 #2: ffff0000cee9a0e0 (&type->s_umount_key#61){.+.+}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:415 #3: ffff0000de4826c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1d4/0x4f8 fs/jfs/inode.c:102 4 locks held by kworker/u4:4/416: #0: ffff0000c40be938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265 #1: ffff80001e6e7c20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267 #2: ffff0000d18ac0e0 (&type->s_umount_key#61){.+.+}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:415 #3: ffff0000e25cb008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1d4/0x4f8 fs/jfs/inode.c:102 2 locks held by getty/3989: #0: ffff0000d0b6a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80001bcd02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1214 drivers/tty/n_tty.c:2188 1 lock held by syz-fuzzer/4224: 1 lock held by syz-executor.4/7636: #0: ffff800015a2a278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #0: ffff800015a2a278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3e0/0x77c kernel/rcu/tree_exp.h:962 4 locks held by syz-executor.2/8579: 2 locks held by kworker/1:14/8722: #0: ffff0000c0021938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265 #1: ffff80001eea7c20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267 4 locks held by syz-executor.1/9438: 4 locks held by kworker/u4:12/9492: #0: ffff0000c40be938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265 #1: ffff80001e267c20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267 #2: ffff0000e81e40e0 (&type->s_umount_key#61){.+.+}-{3:3}, at: trylock_super+0x28/0xf8 fs/super.c:415 #3: ffff0000f2ec01c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1d4/0x4f8 fs/jfs/inode.c:102 2 locks held by kworker/u4:13/9584: 4 locks held by syz-executor.3/10063: 1 lock held by syz-executor.0/11954: #0: ffff800015a2a278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffff800015a2a278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x30c/0x77c kernel/rcu/tree_exp.h:962 =============================================