INFO: task udevd:2843 blocked for more than 143 seconds. Not tainted 6.14.0-rc1-syzkaller-g9682c35ff6ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24304 pid:2843 tgid:2843 ppid:1 task_flags:0x400140 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x113d/0x35d0 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x124/0x330 kernel/locking/rwsem.c:1526 kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 d_revalidate fs/namei.c:928 [inline] d_revalidate fs/namei.c:924 [inline] lookup_fast+0x260/0x5f0 fs/namei.c:1754 walk_component+0x5b/0x5b0 fs/namei.c:2110 link_path_walk.part.0.constprop.0+0x669/0xd40 fs/namei.c:2479 link_path_walk fs/namei.c:2410 [inline] path_lookupat+0x93/0x770 fs/namei.c:2635 filename_lookup+0x221/0x5f0 fs/namei.c:2665 do_readlinkat+0xcf/0x390 fs/stat.c:562 __do_sys_readlink fs/stat.c:599 [inline] __se_sys_readlink fs/stat.c:596 [inline] __x64_sys_readlink+0x78/0xc0 fs/stat.c:596 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe71df82d47 RSP: 002b:00007ffc65617d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007ffc65617d78 RCX: 00007fe71df82d47 RDX: 0000000000000400 RSI: 00007ffc65617d78 RDI: 00007ffc65618258 RBP: 0000000000000400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc65618258 R13: 00007ffc656181c8 R14: 00005631b60eb2c0 R15: 0000000000000000 INFO: task udevd:5909 blocked for more than 172 seconds. Not tainted 6.14.0-rc1-syzkaller-g9682c35ff6ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24304 pid:5909 tgid:5909 ppid:2843 task_flags:0x400140 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x113d/0x35d0 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 device_lock include/linux/device.h:1030 [inline] uevent_show+0x188/0x3b0 drivers/base/core.c:2729 dev_attr_show+0x53/0xe0 drivers/base/core.c:2423 sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59 seq_read_iter+0x4f4/0x12b0 fs/seq_file.c:230 kernfs_fop_read_iter+0x414/0x580 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x886/0xbf0 fs/read_write.c:565 ksys_read+0x12b/0x250 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe71df81b6a RSP: 002b:00007ffc65610d88 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00005631b611ec40 RCX: 00007fe71df81b6a RDX: 0000000000001000 RSI: 00005631b61377b0 RDI: 0000000000000008 RBP: 00005631b611ec40 R08: 0000000000000008 R09: 0000000000000008 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffc65611268 R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff88ebe480 (rcu_read_lock ){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] ){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] ){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by kworker/u8:2/37: #0: ffff888100089148 ( (wq_completion)events_unbound){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90000277d18 ( (work_completion)(&sub_info->work)){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 2 locks held by kworker/u8:4/47: #0: ffff888100089148 ( (wq_completion)events_unbound){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90000527d18 ( (work_completion)(&sub_info->work) ){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 6 locks held by kworker/0:2/929: #0: ffff8881066a5948 ((wq_completion)usb_hub_wq){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90001aefd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810b3a2190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5851 #3: ffff88810b3a5508 (&port_dev->status_lock ){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3209 [inline] ){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5420 [inline] ){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5663 [inline] ){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5823 [inline] ){+.+.}-{4:4}, at: hub_event+0x28aa/0x4f40 drivers/usb/core/hub.c:5905 #4: ffff888107b56068 (hcd->address0_mutex){+.+.}-{4:4} , at: hub_port_connect drivers/usb/core/hub.c:5421 [inline] , at: hub_port_connect_change drivers/usb/core/hub.c:5663 [inline] , at: port_event drivers/usb/core/hub.c:5823 [inline] , at: hub_event+0x28d0/0x4f40 drivers/usb/core/hub.c:5905 #5: ffffffff899dcf70 ( ehci_cf_port_reset_rwsem ){.+.+}-{4:4} , at: hub_port_reset+0x1a7/0x1e60 drivers/usb/core/hub.c:3024 2 locks held by kworker/u8:6/1100: #0: ffff888100089148 ((wq_completion)events_unbound ){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc900020ffd18 ( (work_completion)(&sub_info->work)){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 2 locks held by kworker/1:2/1123: #0: ffff888100080d48 ( (wq_completion)events){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000225fd18 ( free_ipc_work){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 2 locks held by getty/2903: #0: ffff88811219a0a0 (&tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/2945: #0: ffffffff88ec98f8 ( rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:334 1 lock held by syz-executor/2949: 1 lock held by udevd/5193: #0: ffff888100abc148 (&root->kernfs_rwsem){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 1 lock held by udevd/5199: #0: ffff888100abc148 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 4 locks held by kworker/1:3/5200: 1 lock held by udevd/5201: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 6 locks held by kworker/0:3/5233: 1 lock held by udevd/5240: #0: ffff888100abc148 ( &root->kernfs_rwsem){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 1 lock held by udevd/5243: #0: ffff888100abc148 (&root->kernfs_rwsem){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 4 locks held by kworker/0:4/5244: 1 lock held by udevd/5259: #0: ffff888100abc148 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 4 locks held by udevd/5260: #0: ffff888113fe0790 ( &p->lock){+.+.}-{4:4} , at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff88811896cc88 (&of->mutex#2){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888104a9a4b8 (kn->active#21 ){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888112e6b190 (&dev->mutex ){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1035 [inline] ){....}-{4:4}, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143 1 lock held by udevd/5262: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 4 locks held by kworker/1:5/5345: 8 locks held by kworker/0:5/5457: 4 locks held by udevd/5909: #0: ffff888108b6fc30 (&p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888100efb888 ( &of->mutex #2){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888114e86008 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811cf3e190 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1030 [inline] , at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 1 lock held by udevd/5910: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{4:4}, at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 1 lock held by syz.3.415/6904: 1 lock held by syz-executor/6918: 1 lock held by modprobe/6919: #0: ffff888100abc148 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1160 1 lock held by kworker/u8:4/6920: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc1-syzkaller-g9682c35ff6ec #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: yealink 5-1:36.0: urb_irq_callback - urb status -71 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5457 Comm: kworker/0:5 Not tainted 6.14.0-rc1-syzkaller-g9682c35ff6ec #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_power_efficient gc_worker RIP: 0010:mark_lock+0xca/0xc60 kernel/locking/lockdep.c:4729 Code: 01 00 00 00 44 89 f1 41 d3 e5 4d 63 ed 48 89 df e8 5b 67 ff ff 48 ba 00 00 00 00 00 fc ff df 48 8d 78 60 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 a7 09 00 00 4c 89 ee 48 23 70 60 ba 01 00 00 00 RSP: 0018:ffffc90000007290 EFLAGS: 00000806 RAX: ffffffff8fae3c48 RBX: ffff888116592888 RCX: 1ffffffff1f5c795 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff8fae3ca8 RBP: ffffc900000073d0 R08: 0000000000000000 R09: fffffbfff1f5c5c0 R10: ffffffff8fae2e07 R11: 0000000000000004 R12: ffff888116591d40 R13: 0000000000000010 R14: 0000000000000004 R15: 1ffff92000000e58 FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055725dca0068 CR3: 0000000008ca2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4640 [inline] __lock_acquire+0x12fb/0x3c40 kernel/locking/lockdep.c:5182 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 console_lock_spinning_enable+0xb0/0xd0 kernel/printk/printk.c:1924 console_emit_next_record kernel/printk/printk.c:3116 [inline] console_flush_all+0x7ac/0xc60 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0xd9/0x210 kernel/printk/printk.c:3309 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432 dev_vprintk_emit drivers/base/core.c:4890 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4901 __dev_printk+0xf5/0x270 drivers/base/core.c:4913 _dev_err+0xe5/0x120 drivers/base/core.c:4956 urb_irq_callback+0x454/0x700 drivers/input/misc/yealink.c:418 __usb_hcd_giveback_urb+0x389/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x17f7/0x3960 drivers/usb/gadget/udc/dummy_hcd.c:1994 __run_hrtimer kernel/time/hrtimer.c:1738 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1802 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1819 handle_softirqs+0x206/0x8d0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:debug_lockdep_rcu_enabled+0x4/0x40 kernel/rcu/update.c:320 Code: b6 e8 30 fa ff ff eb b6 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <8b> 05 c2 fe 3f 03 85 c0 74 20 8b 05 b0 0d 40 03 85 c0 74 16 65 48 RSP: 0018:ffffc900028d7ac8 EFLAGS: 00000286 RAX: fffff5200051af5c RBX: 1ffff9200051af5c RCX: ffffc900028d7ae0 RDX: 0000000000000000 RSI: 0000000000000644 RDI: ffffffff87fe2b80 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff14ad6d2 R10: ffffffff8a56b697 R11: 0000000000000003 R12: ffffffff87fe2b80 R13: 0000000000000644 R14: dffffc0000000000 R15: 0000000000001770 __might_resched+0x5d/0x5e0 kernel/sched/core.c:8728 gc_worker+0x98d/0x16a0 net/netfilter/nf_conntrack_core.c:1604 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244