INFO: task syz-executor:6427 blocked for more than 143 seconds. Not tainted 6.16.0-rc4-syzkaller-00013-g66701750d556 #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21816 pid:6427 tgid:6427 ppid:1 task_flags:0x40014c flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4cd0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216 sync_inodes_sb+0x1bb/0xa10 fs/fs-writeback.c:2833 sync_filesystem+0x17a/0x230 fs/sync.c:64 generic_shutdown_super+0x6f/0x2c0 fs/super.c:622 kill_block_super+0x44/0x90 fs/super.c:1755 deactivate_locked_super+0xbc/0x110 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x22e0 kernel/exit.c:964 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 __do_sys_exit_group kernel/exit.c:1116 [inline] __se_sys_exit_group kernel/exit.c:1114 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8a/0x300 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f924418e929 RSP: 002b:00007ffc29d482b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f92442109a9 RCX: 00007f924418e929 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000027 R08: 00007ffc29d46056 R09: 00007ffc29d49570 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc29d49570 R13: 00007f9244210925 R14: 00005555801cb4a8 R15: 00007ffc29d4b730 Showing all locks held in the system: 4 locks held by kworker/u8:0/12: 2 locks held by kworker/u8:1/13: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc90000127ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000127ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 1 lock held by khungtaskd/31: #0: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8db3cea0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:2/36: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc90000ac7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000ac7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 #2: ffff8880b8839fd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 2 locks held by kworker/u8:3/49: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc90000b97ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000b97ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 2 locks held by kworker/u8:4/59: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc9000210fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000210fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 2 locks held by kworker/u8:5/1140: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc90003e5fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003e5fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 2 locks held by kworker/u8:6/1322: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc9000436fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000436fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 2 locks held by kworker/u8:8/2969: #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f2d3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1790 kernel/workqueue.c:3321 #1: ffffc9000c2f7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c2f7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1790 kernel/workqueue.c:3321 2 locks held by getty/5539: #0: ffff88814c2320a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/6427: #0: ffff88807b73c0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807b73c0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807b73c0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888142f1a7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff888142f1a7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 2 locks held by syz-executor/6948: #0: ffff888033f780e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff888033f780e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff888033f780e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888142f607d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff888142f607d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 1 lock held by segctord/7025: 2 locks held by syz-executor/7247: #0: ffff88807ebb80e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807ebb80e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807ebb80e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888142f667d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff888142f667d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 2 locks held by syz-executor/7490: #0: ffff88805f5480e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805f5480e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805f5480e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888142f6c7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff888142f6c7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 1 lock held by segctord/7569: 2 locks held by syz-executor/7707: #0: ffff8880302fa0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880302fa0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880302fa0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff8880248c27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880248c27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 2 locks held by syz-executor/7924: #0: ffff88806e4a40e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88806e4a40e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88806e4a40e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff8880248d87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880248d87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 1 lock held by segctord/8000: 2 locks held by syz-executor/8120: #0: ffff88807c1820e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807c1820e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807c1820e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff8880248de7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880248de7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 2 locks held by syz-executor/8306: 2 locks held by dhcpcd/8368: #0: ffff88802a4a2258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline] #0: ffff88802a4a2258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3252 #1: ffffffff8db429b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #1: ffffffff8db429b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998 2 locks held by cmp/8385: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00013-g66701750d556 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0x13f0/0x1430 kernel/hung_task.c:470 kthread+0x711/0x890 kernel/kthread.c:464 ret_from_fork+0x3f5/0x760 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7569 Comm: segctord Not tainted 6.16.0-rc4-syzkaller-00013-g66701750d556 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline] RIP: 0010:lock_acquire+0x13d/0x350 kernel/locking/lockdep.c:5873 Code: 00 6a 00 55 ff 74 24 30 e8 d0 02 00 00 48 83 c4 28 48 c7 c7 f8 e0 47 8d e8 20 4f 74 09 b8 ff ff ff ff 65 0f c1 05 33 0d 80 10 <83> f8 01 0f 85 c7 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24 RSP: 0018:ffffc9000474f200 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 39549b406065fe00 RDX: 00000000aef644dc RSI: ffffffff8d47e0f8 RDI: ffffffff8b7d6fa0 RBP: ffffffff81f69f0d R08: ffffffff8db3cea0 R09: ffffffff81f69f0d R10: ffffc9000474f2e0 R11: fffff520008e9e5f R12: 0000000000000002 R13: ffffffff8db3cea0 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888126751000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5a4466c440 CR3: 000000002f3f8000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] filemap_get_entry+0xc9/0x2f0 mm/filemap.c:1867 __filemap_get_folio+0x68/0xaf0 mm/filemap.c:1915 __find_get_block_slow fs/buffer.c:193 [inline] find_get_block_common+0x214/0xfc0 fs/buffer.c:1414 bdev_getblk+0x4b/0x690 fs/buffer.c:-1 __getblk include/linux/buffer_head.h:382 [inline] sb_getblk include/linux/buffer_head.h:388 [inline] nilfs_segbuf_extend_segsum+0x116/0x3b0 fs/nilfs2/segbuf.c:99 nilfs_segbuf_reset+0x37/0x140 fs/nilfs2/segbuf.c:135 nilfs_segctor_reset_segment_buffer fs/nilfs2/segment.c:423 [inline] nilfs_segctor_collect fs/nilfs2/segment.c:1543 [inline] nilfs_segctor_do_construct+0x1334/0x6a30 fs/nilfs2/segment.c:2122 nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2462 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2570 [inline] nilfs_segctor_thread+0x6f7/0xe00 fs/nilfs2/segment.c:2684 kthread+0x711/0x890 kernel/kthread.c:464 ret_from_fork+0x3f5/0x760 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245