INFO: task udevd:4289 blocked for more than 144 seconds. Not tainted 5.15.180-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24120 pid: 4289 ppid: 3546 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518 __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 device_lock include/linux/device.h:760 [inline] uevent_show+0x17e/0x340 drivers/base/core.c:2408 dev_attr_show+0x50/0xb0 drivers/base/core.c:2110 sysfs_kf_seq_show+0x313/0x4e0 fs/sysfs/file.c:61 seq_read_iter+0x43a/0xd10 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2166 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0xa93/0xe10 fs/read_write.c:485 ksys_read+0x1a2/0x2c0 fs/read_write.c:623 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: 0033:0x7fa320a55b6a RSP: 002b:00007ffd073dd698 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000562d9906abe0 RCX: 00007fa320a55b6a RDX: 0000000000001000 RSI: 0000562d99049260 RDI: 0000000000000008 RBP: 0000562d9906abe0 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffd073ddb78 R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1f560 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:2/154: #0: ffff8880175cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000125fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc38490 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xc90 net/core/net_namespace.c:572 #3: ffffffff8dc44148 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_delete_nets+0xca/0x360 net/ipv4/ip_tunnel.c:1146 1 lock held by dhcpcd/3838: #0: ffffffff8dc44148 (rtnl_mutex){+.+.}-{3:3} , at: rtnl_lock net/core/rtnetlink.c:72 [inline] , at: rtnetlink_rcv_msg+0x956/0xef0 net/core/rtnetlink.c:5647 2 locks held by getty/3923: #0: ffff88802cbe2098 (&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 2 locks held by kworker/0:0/4182: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002dafd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 6 locks held by kworker/0:1/4201: 4 locks held by udevd/4289: #0: ffff88802465bb08 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182 #1: ffff88805efd5488 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112 #2: ffff88805fd10008 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113 #3: ffff88802457a220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff88802457a220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17e/0x340 drivers/base/core.c:2408 3 locks held by kworker/u4:7/4300: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900031afd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc44148 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 2 locks held by kworker/1:12/4384: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900038efd20 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/u4:12/4681: 3 locks held by kworker/0:7/4840: #0: ffff88802bc92938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000317fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc44148 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd8/0x16f0 net/ipv6/addrconf.c:4113 3 locks held by kworker/0:20/6438: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003ccfd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #2: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 3 locks held by kworker/1:13/6757: #0: ffff88802bc92938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003bafd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc44148 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd8/0x16f0 net/ipv6/addrconf.c:4113 3 locks held by syz-executor/7117: #0: ffff888055e40ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x63/0x1070 net/bluetooth/hci_core.c:1737 #1: ffff888055e40078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x431/0x1070 net/bluetooth/hci_core.c:1782 #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 1 lock held by syz.2.423/7388: #0: ffff88805c8620e0 (&type->s_umount_key#75){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 4 locks held by syz-executor/7347: #0: ffff8880672a0ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x63/0x1070 net/bluetooth/hci_core.c:1737 #1: ffff8880672a0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x431/0x1070 net/bluetooth/hci_core.c:1782 #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 #3: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #3: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 3 locks held by syz.0.430/7392: #0: ffff888055f74ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x63/0x1070 net/bluetooth/hci_core.c:1737 #1: ffff888055f74078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x431/0x1070 net/bluetooth/hci_core.c:1782 #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 3 locks held by syz.4.431/7406: #0: ffff88801b5dcff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x63/0x1070 net/bluetooth/hci_core.c:1737 #1: ffff88801b5dc078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x431/0x1070 net/bluetooth/hci_core.c:1782 #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline] #2: ffffffff8dd8ec08 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb8/0x220 net/bluetooth/hci_conn.c:1622 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:212 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:369 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: 4300 Comm: kworker/u4:7 Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:__list_add_valid+0x6a/0xe0 lib/list_debug.c:30 Code: 48 89 df e8 b8 d6 b1 fd 48 8b 13 4c 39 e2 75 68 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 9a d6 b1 fd 49 8b 14 24 <4c> 39 f2 75 5d 4d 39 e7 74 11 4d 39 f7 74 0c b0 01 5b 41 5c 41 5d RSP: 0018:ffffc90000007a98 EFLAGS: 00000046 RAX: 1ffff1100b1a32dd RBX: ffff88802ac2dc70 RCX: ffffffff8153da5c RDX: ffff88802ac2dc68 RSI: ffff888058d196e8 RDI: ffff88807c36d6e8 RBP: ffff888058d196e8 R08: dffffc0000000000 R09: ffffed100f86dadd R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888058d196e8 R13: dffffc0000000000 R14: ffff88802ac2dc68 R15: ffff88807c36d6e8 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd03927ca8 CR3: 000000002b4b1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_add include/linux/list.h:67 [inline] list_add_tail include/linux/list.h:100 [inline] insert_work+0x12e/0x3e0 kernel/workqueue.c:1370 __queue_work+0x963/0xd00 kernel/workqueue.c:1532 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1491 [inline] __run_timers+0x6a8/0x890 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 4c ad 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900031afa80 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000635f5c RCX: 1ffff92000635efc RDX: dffffc0000000000 RSI: ffffffff8aab3e00 RDI: ffffffff8af9fc80 RBP: ffffc900031afbd8 R08: dffffc0000000000 R09: fffffbfff2132219 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000635f58 R13: dffffc0000000000 R14: ffffc900031afae0 R15: 0000000000000246 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0xc1/0x5b0 net/batman-adv/network-coding.c:723 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