INFO: task kworker/u8:2:34 blocked for more than 143 seconds. Not tainted 6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:2 state:D stack:20056 pid:34 tgid:34 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6895 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 jfs_commit_inode+0x24a/0x590 fs/jfs/inode.c:102 jfs_write_inode+0x143/0x220 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1498 [inline] __writeback_single_inode+0x6b9/0x10b0 fs/fs-writeback.c:1715 writeback_sb_inodes+0x905/0x1260 fs/fs-writeback.c:1941 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2012 wb_writeback+0x46b/0xce0 fs/fs-writeback.c:2119 wb_check_old_data_flush fs/fs-writeback.c:2223 [inline] wb_do_writeback fs/fs-writeback.c:2276 [inline] wb_workfn+0xba1/0x1090 fs/fs-writeback.c:2304 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 4 locks held by kworker/u8:2/34: #0: ffff88801bac7148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff88801bac7148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc90000aa7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc90000aa7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffff888066ca60e0 (&type->s_umount_key#89){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:561 #3: ffff88804b649448 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x24a/0x590 fs/jfs/inode.c:102 2 locks held by kworker/u8:5/154: #0: ffff888015089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff888015089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffff8880b9528948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 4 locks held by kworker/u8:7/2451: #0: ffff88801bac7148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff88801bac7148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc90009b37d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc90009b37d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffff88802d92a0e0 (&type->s_umount_key#89){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:561 #3: ffff88807094e788 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x24a/0x590 fs/jfs/inode.c:102 2 locks held by getty/4828: #0: ffff88802a71b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 4 locks held by syz-executor.4/12232: 1 lock held by syz-executor.2/13083: #0: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x463/0x820 kernel/rcu/tree_exp.h:939 4 locks held by syz-executor.3/13138: 1 lock held by syz-executor.1/14936: #0: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x463/0x820 kernel/rcu/tree_exp.h:939 2 locks held by syz-executor.3/14974: #0: ffff8880b943e658 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #1: ffff8880b9428948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 1 lock held by syz-executor.3/14980: #0: ffff8880b953e658 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:380 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 13138 Comm: syz-executor.3 Not tainted 6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x46/0x70 kernel/kcov.c:212 Code: ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 14 16 00 00 00 74 2c 8b 91 f0 15 00 00 83 fa 02 75 21 48 8b 91 f8 15 00 00 48 8b 32 <48> 8d 7e 01 8b 89 f4 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 RSP: 0018:ffffc9000fb07498 EFLAGS: 00000246 RAX: ffffffff83238699 RBX: 0000000000000000 RCX: ffff888029719e00 RDX: ffffc90014a0d000 RSI: 000000000003ffff RDI: 00000000000000ff RBP: ffffc9000fb07690 R08: ffffffff83238690 R09: 0000000000000000 R10: 00300065006c0069 R11: 006605ff00000020 R12: ffff88806aa23000 R13: dffffc0000000000 R14: ffff88807094e9f0 R15: 0000000000000000 FS: 00007eff5a7186c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd8060d56c6 CR3: 0000000048086000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dtSplitRoot+0x8b9/0x1930 fs/jfs/jfs_dtree.c:1976 dtSplitUp fs/jfs/jfs_dtree.c:990 [inline] dtInsert+0x12fa/0x6b00 fs/jfs/jfs_dtree.c:868 jfs_mkdir+0x7fb/0xb90 fs/jfs/namei.c:270 vfs_mkdir+0x2f9/0x4b0 fs/namei.c:4123 do_mkdirat+0x264/0x3a0 fs/namei.c:4146 __do_sys_mkdirat fs/namei.c:4161 [inline] __se_sys_mkdirat fs/namei.c:4159 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4159 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7eff59a7dea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007eff5a7180c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007eff59babf80 RCX: 00007eff59a7dea9 RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000007 RBP: 00007eff59aca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007eff59babf80 R15: 00007ffcfafadcc8