INFO: task kworker/u4:2:548 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D26048 548 2 0x80000000 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078 f2fs_balance_fs+0x709/0xd80 fs/f2fs/segment.c:512 f2fs_write_inode+0x500/0x600 fs/f2fs/inode.c:630 write_inode fs/fs-writeback.c:1244 [inline] __writeback_single_inode+0x733/0x11d0 fs/fs-writeback.c:1442 writeback_sb_inodes+0x537/0xef0 fs/fs-writeback.c:1647 __writeback_inodes_wb+0xc6/0x280 fs/fs-writeback.c:1716 wb_writeback+0x841/0xcc0 fs/fs-writeback.c:1822 wb_check_old_data_flush fs/fs-writeback.c:1924 [inline] wb_do_writeback fs/fs-writeback.c:1977 [inline] wb_workfn+0x8ba/0x1250 fs/fs-writeback.c:2006 Bluetooth: hci6: command 0x0406 tx timeout process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 2 locks held by kworker/u4:1/23: 1 lock held by khungtaskd/1569: #0: 00000000cb47e2ac (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7847: F2FS-fs (loop0): invalid crc value #0: 0000000041487971 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 4 locks held by kworker/u4:2/548: #0: 000000000e866f0d ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 F2FS-fs (loop0): Found nat_bits in checkpoint #1: 000000006cfe7f56 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000238a252b (&type->s_umount_key#68){++++}, at: trylock_super+0x1d/0x100 fs/super.c:412 #3: 0000000093c8d90d (&sbi->gc_mutex){+.+.}, at: f2fs_balance_fs+0x709/0xd80 fs/f2fs/segment.c:512 3 locks held by kworker/u4:5/28517: F2FS-fs (loop0): Mounted with checkpoint version = 48b305e4 #0: 00000000feaf329d ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 kauditd_printk_skb: 62 callbacks suppressed audit: type=1800 audit(1676334370.055:9493): pid=18002 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="bus" dev="sda1" ino=13936 res=0 #1: 00000000723b569f (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 IPVS: ftp: loaded support on port[0] = 21 audit: type=1800 audit(1676334370.105:9494): pid=18005 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="bus" dev="sda1" ino=13936 res=0 #2: 000000006f9fe58f (rcu_preempt_state.barrier_mutex){+.+.}, at: _rcu_barrier+0x59/0x3e0 kernel/rcu/tree.c:3430 5 locks held by syz-executor.3/13559: 2 locks held by kworker/0:1/14261: #0: 0000000070e2f2b2 ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000003c9f2a11 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 2 locks held by syz-executor.3/17941: 2 locks held by syz-executor.4/17986: 2 locks held by syz-executor.1/17992: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1569 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4690 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 RIP: 0010:write_comp_data+0x6c/0x70 kernel/kcov.c:146 Code: 00 00 4e 8d 04 dd 28 00 00 00 4c 39 c6 72 1b 48 83 c7 01 4e 89 54 00 e0 4e 89 4c 00 e8 4a 89 54 00 f0 4a 89 4c d8 20 48 89 38 0f 1f 00 48 8b 0c 24 40 0f b6 d6 40 0f b6 f7 31 ff eb 80 48 8b RSP: 0018:ffff8880a0d77dc8 EFLAGS: 00040293 RAX: 0000000000000000 RBX: 0000000000000030 RCX: ffffffff83888289 RDX: 0000000000000000 RSI: ffff8880a0d6e500 RDI: 0000000000000005 RBP: 0000000000000fb0 R08: 0000000000000fe0 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000000 R12: 6d65747379732f64 R13: 0000563ee205e890 R14: ffff88809f156ae0 R15: 0000000000000000 FS: 00007f7d875498c0(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7d82063010 CR3: 00000000a1bf3000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: do_strncpy_from_user lib/strncpy_from_user.c:39 [inline] strncpy_from_user+0x1f9/0x350 lib/strncpy_from_user.c:119 getname_flags+0x113/0x590 fs/namei.c:151 do_sys_open+0x26c/0x520 fs/open.c:1079 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f7d86ad885d Code: bb 20 00 00 75 10 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 67 f6 ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffff3682740 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffff3682a50 RCX: 00007f7d86ad885d RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000563ee205e890 RBP: 000000000000000d R08: 00000000000001c0 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000293 R12: 00000000ffffffff R13: 0000563ee2052040 R14: 00007ffff3682a10 R15: 0000563ee205e060