INFO: task udevd:2843 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24552 pid:2843 tgid:2843 ppid:1 task_flags:0x400140 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x132a/0x3b00 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x62f/0xb60 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0xef/0x480 kernel/locking/rwsem.c:1526 kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1178 d_revalidate fs/namei.c:929 [inline] d_revalidate fs/namei.c:925 [inline] lookup_fast+0x263/0x610 fs/namei.c:1778 walk_component+0x5b/0x5b0 fs/namei.c:2134 link_path_walk.part.0.constprop.0+0x685/0xd60 fs/namei.c:2503 link_path_walk fs/namei.c:2435 [inline] path_openat+0x227/0x2d40 fs/namei.c:4035 do_filp_open+0x20b/0x470 fs/namei.c:4066 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f92b279a407 RSP: 002b:00007ffd505113c0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f92b26ac880 RCX: 00007f92b279a407 RDX: 0000000000080000 RSI: 00007ffd50511540 RDI: ffffffffffffff9c RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055ea4c83a7f5 R13: 000055ea4c83a7f5 R14: 0000000000000001 R15: 0000000000000000 INFO: task syz.2.131:5685 blocked for more than 171 seconds. Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.131 state:D stack:27640 pid:5685 tgid:5684 ppid:2958 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x132a/0x3b00 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0x524/0x1310 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d6/0x200 kernel/locking/rwsem.c:1578 kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1709 sysfs_remove_file include/linux/sysfs.h:794 [inline] driver_remove_file drivers/base/driver.c:201 [inline] driver_remove_file+0x4a/0x60 drivers/base/driver.c:197 remove_bind_files drivers/base/bus.c:605 [inline] bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743 driver_unregister+0x76/0xb0 drivers/base/driver.c:277 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1732 raw_release+0x1ae/0x2b0 drivers/usb/gadget/legacy/raw_gadget.c:462 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xafb/0x2c30 kernel/exit.c:953 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3b8663e56b RSP: 002b:00007f3b84ca4f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007f3b8663e56b RDX: 00007f3b84ca5fe0 RSI: 0000000080085502 RDI: 0000000000000003 RBP: 00007f3b84ca5fe0 R08: 0000000000000080 R09: 00007f3b84ca4fd8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502 R13: 0000000800000000 R14: 0000000000000009 R15: 00007f3b866cba1e INFO: task syz.0.132:5687 blocked for more than 172 seconds. Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.132 state:D stack:27640 pid:5687 tgid:5686 ppid:2954 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x132a/0x3b00 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0x524/0x1310 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d6/0x200 kernel/locking/rwsem.c:1578 kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1709 sysfs_remove_file include/linux/sysfs.h:794 [inline] driver_remove_file drivers/base/driver.c:201 [inline] driver_remove_file+0x4a/0x60 drivers/base/driver.c:197 remove_bind_files drivers/base/bus.c:605 [inline] bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743 driver_unregister+0x76/0xb0 drivers/base/driver.c:277 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1732 raw_release+0x1ae/0x2b0 drivers/usb/gadget/legacy/raw_gadget.c:462 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xafb/0x2c30 kernel/exit.c:953 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5be820e56b RSP: 002b:00007f5be6874f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007f5be820e56b RDX: 00007f5be6875fe0 RSI: 0000000080085502 RDI: 0000000000000003 RBP: 00007f5be6875fe0 R08: 0000000000000080 R09: 00007f5be6874fd8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502 R13: 0000000800000000 R14: 0000000000000008 R15: 00007f5be829ba1e Showing all locks held in the system: 2 locks held by ksoftirqd/1/22: 1 lock held by khungtaskd/30: #0: ffffffff890c2840 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:841 [inline] , at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 4 locks held by kworker/1:1/43: #0: ffff8881072ad948 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900002d7d18 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810ab89198 ( &dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:922 [inline] , at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5863 #3: ffff888100ac4948 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:791 6 locks held by kworker/1:2/1119: 1 lock held by udevd/2843: #0: ffff888100ac4948 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1178 2 locks held by getty/2905: #0: ffff888111fcf0a0 (&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+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/2952: #0: ffff888100ac4948 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1160 1 lock held by syz-executor/2953: #0: ffff888100ac4948 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1160 1 lock held by syz-executor/2954: #0: ffff888100ac4948 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1160 1 lock held by syz-executor/2957: 1 lock held by syz-executor/2958: 1 lock held by udevd/5219: 3 locks held by kworker/1:5/5240: 1 lock held by syz.1.128/5677: 2 locks held by syz.2.131/5685: #0: ffff88810ab94d78 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:922 [inline] , at: __device_driver_lock drivers/base/dd.c:1094 [inline] , at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1292 #1: ffff888100ac4948 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1709 1 lock held by syz.4.133/5689: #0: ffff888100ac4948 ( &root->kernfs_rwsem){++++}-{4:4} , at: kernfs_activate fs/kernfs/dir.c:1423 [inline] , at: kernfs_add_one+0x349/0x840 fs/kernfs/dir.c:834 1 lock held by syz-executor/5695: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: yealink 4-1:36.0: urb_irq_callback - urb status -71 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5691 Comm: syz-executor Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:416 Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 e1 88 09 ff eb a0 e8 6a 89 09 RSP: 0018:ffffc900001a84f0 EFLAGS: 00000002 RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff82cea765 RDI: ffffffff938c7800 RBP: ffffffff938c77c0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 000000000000005b R14: ffffffff938c77c0 R15: ffffffff82cea700 FS: 000055557a356500(0000) GS:ffff8882692c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe5ed41c780 CR3: 0000000124146000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_out include/linux/serial_core.h:796 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3306 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline] serial8250_console_write+0xfbc/0x1890 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x7fe/0xc60 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 dev_vprintk_emit drivers/base/core.c:4917 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928 __dev_printk+0xf5/0x270 drivers/base/core.c:4940 _dev_err+0xe4/0x120 drivers/base/core.c:4983 urb_irq_callback+0x454/0x700 drivers/input/misc/yealink.c:418 __usb_hcd_giveback_urb+0x38a/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x180e/0x3a20 drivers/usb/gadget/udc/dummy_hcd.c:1994 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x205/0x8d0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 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:fd_install+0x10b/0x670 fs/file.c:647 Code: 8d 7d 04 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 c6 03 00 00 <45> 0f b6 65 04 31 ff 44 89 e6 e8 76 4f 94 ff 45 84 e4 0f 85 94 02 RSP: 0018:ffffc900017f7d80 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888113ad6fc0 RCX: ffffffff81e817b7 RDX: 0000000000000004 RSI: ffffffff81e81670 RDI: ffff888112c003c4 RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: ffff888112c003c0 R14: 00000000ffffff9c R15: dffffc0000000000 do_sys_openat2+0x145/0x1d0 fs/open.c:1434 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f029869d251 Code: 75 57 89 f0 25 00 00 41 00 3d 00 00 41 00 74 49 80 3d fa 72 1f 00 00 74 6d 89 da 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 93 00 00 00 48 8b 54 24 28 64 48 2b 14 25 RSP: 002b:00007fff8442d580 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f029869d251 RDX: 0000000000000002 RSI: 00007f0298720b56 RDI: 00000000ffffff9c RBP: 00007f0298720b56 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000