INFO: task kworker/u8:6:1113 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:6 state:D stack:22488 pid:1113 tgid:1113 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-bcachefs-1) Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_lock include/linux/pagemap.h:1148 [inline] writeback_get_folio mm/page-writeback.c:2496 [inline] writeback_iter+0x992/0x18d0 mm/page-writeback.c:2590 write_cache_pages+0xb1/0x230 mm/page-writeback.c:2639 bch2_writepages+0x14f/0x380 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 __writeback_single_inode+0x14f/0x10d0 fs/fs-writeback.c:1658 writeback_sb_inodes+0x80c/0x1370 fs/fs-writeback.c:1954 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2025 wb_writeback+0x42f/0xbd0 fs/fs-writeback.c:2136 wb_check_background_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2294 [inline] wb_workfn+0xc58/0x1090 fs/fs-writeback.c:2321 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.2.3:5329 blocked for more than 145 seconds. Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3 state:D stack:22928 pid:5329 tgid:5300 ppid:5226 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3189 folio_prepare_writeback mm/page-writeback.c:2455 [inline] writeback_get_folio mm/page-writeback.c:2497 [inline] writeback_iter+0xb18/0x18d0 mm/page-writeback.c:2590 write_cache_pages+0xb1/0x230 mm/page-writeback.c:2639 bch2_writepages+0x14f/0x380 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:398 __filemap_fdatawrite_range mm/filemap.c:431 [inline] filemap_write_and_wait_range+0x192/0x280 mm/filemap.c:685 bch2_extend fs/bcachefs/fs-io.c:378 [inline] bchfs_truncate+0x64b/0xc70 fs/bcachefs/fs-io.c:431 notify_change+0xbca/0xe90 fs/attr.c:503 do_truncate+0x220/0x310 fs/open.c:65 vfs_truncate+0x2e1/0x3b0 fs/open.c:111 do_sys_truncate+0xdb/0x190 fs/open.c:134 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f14a477def9 RSP: 002b:00007f14a553e038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007f14a4936058 RCX: 00007f14a477def9 RDX: 0000000000000000 RSI: 000000000000f000 RDI: 0000000020000080 RBP: 00007f14a47f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f14a4936058 R15: 00007fff4eb16ee8 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by khungtaskd/30: #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/1:1/46: 6 locks held by kworker/u8:5/1107: #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900045a7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900045a7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb2910 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffff8880568cf0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8880568cf0e8 (&dev->mutex){....}-{3:3}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff8880568cf0e8 (&dev->mutex){....}-{3:3}, at: devlink_pernet_pre_exit+0x13b/0x440 net/devlink/core.c:506 #4: ffff888064fc1250 (&devlink->lock_key#12){+.+.}-{3:3}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff888064fc1250 (&devlink->lock_key#12){+.+.}-{3:3}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888064fc1250 (&devlink->lock_key#12){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x14d/0x440 net/devlink/core.c:506 #5: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 3 locks held by kworker/u8:6/1113: #0: ffff888141ad2148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888141ad2148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90004507d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90004507d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff8880249760e0 (&type->s_umount_key#59){.+.+}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 2 locks held by getty/4975: #0: ffff88802efd70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:7/5271: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003f07d00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003f07d00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #2: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz.2.3/5301: #0: ffff888024976420 (sb_writers#13){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x220 fs/splice.c:1163 2 locks held by syz.2.3/5329: #0: ffff888024976420 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88805dd588c0 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88805dd588c0 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:63 3 locks held by bch-copygc/loop/5321: 2 locks held by syz.2.49/5576: #0: ffff8880249760e0 (&type->s_umount_key#59){.+.+}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880249760e0 (&type->s_umount_key#59){.+.+}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff8880249747d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff8880249747d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2797 3 locks held by syz-executor/6227: #0: ffff888045d7cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff888045d7cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff888045d7c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fe2bbe8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fe2bbe8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2589 2 locks held by syz.3.178/6623: #0: ffff8880249760e0 (&type->s_umount_key#59){.+.+}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880249760e0 (&type->s_umount_key#59){.+.+}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff8880249747d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff8880249747d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2797 3 locks held by syz.1.189/6711: #0: ffff8880312d0d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff8880312d0d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff8880312d0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fe2bbe8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fe2bbe8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2589 2 locks held by syz-executor/6716: #0: ffffffff8fcb2910 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 1 lock held by dhcpcd/6719: #0: ffff88807ac19408 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff88807ac19408 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88807ac19408 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 1 lock held by syz.2.194/6721: #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 2 locks held by dhcpcd/6722: #0: ffff888056723808 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff888056723808 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff888056723808 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 #1: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by dhcpcd/6723: #0: ffff888056723208 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff888056723208 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff888056723208 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 1 lock held by dhcpcd/6724: #0: ffff888056722008 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff888056722008 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff888056722008 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 1 lock held by dhcpcd/6726: #0: ffff888056720e08 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff888056720e08 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff888056720e08 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 1 lock held by dhcpcd/6727: #0: ffff88805ddf6e08 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #0: ffff88805ddf6e08 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88805ddf6e08 (&sb->s_type->i_mutex_key#9){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1427 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5321 Comm: bch-copygc/loop Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:reacquire_held_locks+0x60d/0x690 kernel/locking/lockdep.c:5343 Code: 00 75 1c 90 48 c7 c7 e0 c8 0a 8c 48 c7 c6 20 c9 0a 8c e8 86 df e4 ff 48 89 d9 90 0f 0b 90 90 90 31 c0 e9 6d ff ff ff 49 89 cf <48> c7 c1 40 c9 38 9a 80 e1 07 80 c1 03 38 c1 4c 89 f9 0f 8c 76 fa RSP: 0018:ffffc90003fb70c0 EFLAGS: 00000002 RAX: 0000000000000004 RBX: ffff8880282d5a00 RCX: 1ffff920007f6e28 RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff8880282d5a00 RBP: ffffc90003fb71d0 R08: ffffffff901bb96f R09: 1ffffffff203772d R10: dffffc0000000000 R11: fffffbfff203772e R12: dffffc0000000000 R13: 0000000000000001 R14: 0000000000000002 R15: 1ffff920007f6e28 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000563420533058 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_release kernel/locking/lockdep.c:5536 [inline] lock_release+0x396/0xa30 kernel/locking/lockdep.c:5843 trans_set_unlocked fs/bcachefs/btree_locking.h:206 [inline] bch2_trans_unlock+0x34b/0x470 fs/bcachefs/btree_locking.c:812 bch2_trans_begin+0x862/0x1c00 fs/bcachefs/btree_iter.c:3100 bch2_copygc_get_buckets fs/bcachefs/movinggc.c:164 [inline] bch2_copygc+0x86b/0x4650 fs/bcachefs/movinggc.c:215 bch2_copygc_thread+0x737/0xc20 fs/bcachefs/movinggc.c:375 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244