INFO: task kworker/u4:7:4267 blocked for more than 186 seconds. Not tainted 5.15.175-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:21048 pid: 4267 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102 jfs_write_inode+0x13f/0x210 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1495 [inline] __writeback_single_inode+0x644/0xe30 fs/fs-writeback.c:1705 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106 wb_check_old_data_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2259 [inline] wb_workfn+0xc55/0x1130 fs/fs-writeback.c:2288 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Showing all locks held in the system: 3 locks held by kworker/1:1/23: #0: ffff88814c668d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90000ddfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc419c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113 1 lock held by khungtaskd/27: #0: ffffffff8cb1fd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:2/154: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffff8880b8f27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891 #2: ffff88813fe68a28 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4027 2 locks held by kworker/u4:3/155: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90001ef7d20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 1 lock held by dhcpcd/3838: #0: ffffffff8dc419c8 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xd5/0xca0 net/netlink/af_netlink.c:2212 2 locks held by getty/3924: #0: ffff88802c113098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cd62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/4166: #0: ffffffff8dc419c8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline] #0: ffffffff8dc419c8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3440 2 locks held by kworker/1:5/4211: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000302fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by kworker/1:8/4239: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900030dfd20 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8cb241f0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039 4 locks held by kworker/u4:7/4267: #0: ffff888144784938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900031efd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff888028b700e0 (&type->s_umount_key#67){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418 #3: ffff888071d43008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102 2 locks held by kworker/1:10/4497: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000330fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/1:17/4508: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900041cfd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by syz.2.261/5719: #0: ffff88802b034ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x63/0x1070 net/bluetooth/hci_core.c:1737 #1: ffff88802b034078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x431/0x1070 net/bluetooth/hci_core.c:1782 #2: ffffffff8dd8ad28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffffffff8dd8ad28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 4 locks held by syz.4.297/5873: 3 locks held by kworker/1:21/6233: #0: ffff88814c668d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90004a7fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc419c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113 4 locks held by kworker/u4:12/6392: #0: ffff8880175cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000427fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc35dd0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:561 #3: ffffffff8dc419c8 (rtnl_mutex){+.+.}-{3:3}, at: fib6_rules_net_exit+0xe/0x50 net/ipv6/fib6_rules.c:506 1 lock held by syz-executor/7097: #0: ffffffff8cb242e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8cb242e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 1 lock held by syz-executor/7472: #0: ffffffff8cb242e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #0: ffffffff8cb242e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 2 locks held by syz.8.533/7505: #0: ffff888020cc4518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912 #1: ffff888147476468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070 1 lock held by dhcpcd/7534: #0: ffff888057b18120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff888057b18120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/7535: #0: ffff88806a1bc120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff88806a1bc120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/7536: #0: ffff88807dd98120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff88807dd98120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/7537: #0: ffff888077dbe120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff888077dbe120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/7538: #0: ffff88807ce86120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff88807ce86120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/7539: #0: ffff88805806c120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff88805806c120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/7540: #0: ffff888142bf2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff888142bf2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5873 Comm: syz.4.297 Not tainted 5.15.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:202 Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d c8 dd 89 0c 48 89 de 5b e9 07 05 49 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d d4 ea 81 7e 65 8b 15 d5 ea 81 7e 81 e2 00 RSP: 0018:ffffc9000319f018 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000000080000 RDX: ffff88802bfa1dc0 RSI: 0000000000000000 RDI: 00000000000000ff RBP: ffffc9000319f210 R08: ffffffff82ee3f8c R09: ffffed100c9dc424 R10: 0000000000000004 R11: dffffc0000000001 R12: ffff888064ee2000 R13: dffffc0000000000 R14: ffff888071d43270 R15: 0000000000000000 FS: 00007fdcdc3e36c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055823f1547f8 CR3: 00000000743f1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dtSplitRoot+0x8b5/0x1920 fs/jfs/jfs_dtree.c:1976 dtSplitUp fs/jfs/jfs_dtree.c:990 [inline] dtInsert+0x12f6/0x6b00 fs/jfs/jfs_dtree.c:868 jfs_create+0x7b2/0xbb0 fs/jfs/namei.c:137 lookup_open fs/namei.c:3462 [inline] open_last_lookups fs/namei.c:3532 [inline] path_openat+0x130a/0x2f20 fs/namei.c:3739 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fdcde572d29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdcdc3e3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fdcde762fa0 RCX: 00007fdcde572d29 RDX: 000000000000275a RSI: 0000000020000100 RDI: ffffffffffffff9c RBP: 00007fdcde5eeb08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdcde762fa0 R15: 00007ffd869ac1e8