INFO: task kworker/u8:7:2453 blocked for more than 143 seconds. Not tainted 6.10.0-rc6-syzkaller-00223-gc6653f49e4fd #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:7 state:D stack:20272 pid:2453 tgid:2453 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x1796/0x49d0 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306 f2fs_down_write fs/f2fs/f2fs.h:2170 [inline] f2fs_issue_checkpoint+0x2d6/0x4e0 fs/f2fs/checkpoint.c:1871 f2fs_balance_fs_bg+0x534/0x970 fs/f2fs/segment.c:520 f2fs_write_node_pages+0x147/0x6d0 fs/f2fs/node.c:2136 do_writepages+0x359/0x870 mm/page-writeback.c:2656 __writeback_single_inode+0x165/0x10b0 fs/fs-writeback.c:1651 writeback_sb_inodes+0x99c/0x1380 fs/fs-writeback.c:1947 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2018 wb_writeback+0x495/0xd40 fs/fs-writeback.c:2129 wb_check_old_data_flush fs/fs-writeback.c:2233 [inline] wb_do_writeback fs/fs-writeback.c:2286 [inline] wb_workfn+0xba1/0x1090 fs/fs-writeback.c:2314 process_one_work kernel/workqueue.c:3248 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3329 worker_thread+0x86d/0xd50 kernel/workqueue.c:3409 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 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e333f20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e333f20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e333f20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/1:1/45: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc90000b57d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc90000b57d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 #2: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u8:5/182: #0: ffff888028bf7948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888028bf7948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc90002d3fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc90002d3fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 #2: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4193 4 locks held by kworker/u8:7/2453: #0: ffff88801bef1948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff88801bef1948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc900093bfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc900093bfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 #2: ffff88805f9540e0 (&type->s_umount_key#95){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 #3: ffff8880609a92a0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2170 [inline] #3: ffff8880609a92a0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_issue_checkpoint+0x2d6/0x4e0 fs/f2fs/checkpoint.c:1871 6 locks held by kworker/u8:8/2898: #0: ffff888015ed3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015ed3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc9000a08fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc9000a08fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 #2: ffffffff8f5c80d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffff88807d4e30e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff88807d4e30e8 (&dev->mutex){....}-{3:3}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88807d4e30e8 (&dev->mutex){....}-{3:3}, at: devlink_pernet_pre_exit+0x13b/0x440 net/devlink/core.c:506 #4: ffff88807e61c250 (&devlink->lock_key#14){+.+.}-{3:3}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff88807e61c250 (&devlink->lock_key#14){+.+.}-{3:3}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88807e61c250 (&devlink->lock_key#14){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x14d/0x440 net/devlink/core.c:506 #5: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:678 [inline] #5: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: nsim_create+0x408/0x890 drivers/net/netdevsim/netdev.c:750 1 lock held by dhcpcd/4747: #0: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101 2 locks held by getty/4836: #0: ffff88802ae2c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2211 2 locks held by kworker/0:4/5128: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc90004227d00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc90004227d00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 2 locks held by syz.2.3/5164: 5 locks held by syz.0.144/6215: 3 locks held by syz-executor/7272: #0: ffff8880634a4d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:510 [inline] #0: ffff8880634a4d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2728 #1: ffff8880634a4078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x494/0xf60 net/bluetooth/hci_sync.c:5063 #2: ffffffff8f73f008 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1982 [inline] #2: ffffffff8f73f008 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2593 2 locks held by syz-executor/8122: #0: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x1180 net/core/rtnetlink.c:6632 #1: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:939 5 locks held by syz.1.392/8204: 1 lock held by syz-executor/8229: #0: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f5d4908 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x1180 net/core/rtnetlink.c:6632 4 locks held by syz.0.398/8231: #0: ffff888023ac8d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:510 [inline] #0: ffff888023ac8d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2728 #1: ffff888023ac8078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x494/0xf60 net/bluetooth/hci_sync.c:5063 #2: ffffffff8f73f008 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1982 [inline] #2: ffffffff8f73f008 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2593 #3: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #3: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:939 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc6-syzkaller-00223-gc6653f49e4fd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 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 PID: 4747 Comm: dhcpcd Not tainted 6.10.0-rc6-syzkaller-00223-gc6653f49e4fd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:99 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x52c/0x2a00 arch/x86/kernel/unwind_orc.c:494 Code: 48 01 dd 48 89 ef 4c 89 f6 e8 20 34 55 00 48 8d 43 04 4c 39 f5 4c 0f 46 e8 48 8d 43 fc 4c 0f 47 e0 4c 0f 46 fb 4d 39 e5 77 1d 9f 31 55 00 eb 96 89 d9 80 e1 07 80 c1 03 38 c1 7c c0 48 89 df RSP: 0018:ffffc90004857428 EFLAGS: 00000246 RAX: ffffffff9024c2b0 RBX: ffffffff9024c2b4 RCX: ffff888028fe3c00 RDX: ffff888028fe3c00 RSI: ffffffff8b7cd462 RDI: ffffffff8b7cd4c6 RBP: ffffffff8b7cd4c6 R08: ffffffff8140f500 R09: ffffc900048575f0 R10: 0000000000000003 R11: ffffffff8181dca0 R12: ffffffff9024c2b0 R13: ffffffff9024c2b0 R14: ffffffff8b7cd462 R15: ffffffff9024c2b0 FS: 00007fcde45b2740(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcc28d5ff8 CR3: 0000000020f5a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2196 [inline] slab_free mm/slub.c:4438 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4513 netlink_recvmsg+0x60a/0x11d0 net/netlink/af_netlink.c:1983 sock_recvmsg_nosec net/socket.c:1046 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1068 ____sys_recvmsg+0x1db/0x470 net/socket.c:2804 ___sys_recvmsg net/socket.c:2846 [inline] __sys_recvmsg+0x2f0/0x3e0 net/socket.c:2876 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: 0033:0x7fcde468a91e Code: ff 89 ef 48 89 04 24 e8 4f 57 f9 ff 48 8b 04 24 48 83 c4 30 5d c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 21 b8 2f 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 70 48 8b 15 db c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc87111808 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 00007ffc87112930 RCX: 00007fcde468a91e RDX: 0000000000000000 RSI: 00007ffc87112850 RDI: 000000000000000f RBP: 00007ffc871128c0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000000fe R11: 0000000000000246 R12: 0000000000000ed0 R13: 00007ffc87112834 R14: 00007ffc87112850 R15: 00007ffc87112840