INFO: task udevd:2403 blocked for more than 143 seconds. Not tainted 6.10.0-rc2-syzkaller-00024-g5821bf2dffbe #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:26720 pid:2403 tgid:2403 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xca6/0x3170 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x124/0x330 kernel/locking/rwsem.c:1528 kernfs_dop_revalidate+0xf0/0x5a0 fs/kernfs/dir.c:1159 d_revalidate fs/namei.c:861 [inline] d_revalidate fs/namei.c:858 [inline] lookup_fast+0x239/0x540 fs/namei.c:1653 walk_component+0x5b/0x5b0 fs/namei.c:2000 link_path_walk.part.0.constprop.0+0x77f/0xcd0 fs/namei.c:2331 link_path_walk fs/namei.c:2255 [inline] path_lookupat+0x93/0x770 fs/namei.c:2492 filename_lookup+0x1e5/0x5b0 fs/namei.c:2522 user_path_at_empty+0x42/0x60 fs/namei.c:2929 do_readlinkat+0xdd/0x310 fs/stat.c:499 __do_sys_readlink fs/stat.c:532 [inline] __se_sys_readlink fs/stat.c:529 [inline] __x64_sys_readlink+0x78/0xc0 fs/stat.c:529 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: 0033:0x7fe27a8ced47 RSP: 002b:00007ffdb89d5448 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007ffdb89d5458 RCX: 00007fe27a8ced47 RDX: 0000000000000400 RSI: 00007ffdb89d5458 RDI: 00007ffdb89d5938 RBP: 0000000000000400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdb89d5938 R13: 00007ffdb89d58a8 R14: 0000555d3b4ec910 R15: 0000000000000000 Showing all locks held in the system: 5 locks held by kworker/0:0/8: 6 locks held by kworker/0:1/9: 1 lock held by khungtaskd/30: #0: ffffffff886b4620 ( rcu_read_lock ){....}-{1:2} , at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] , at: rcu_read_lock include/linux/rcupdate.h:781 [inline] , at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by kworker/1:1/42: #0: ffff888100080948 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc900002c7d80 (free_ipc_work ){+.+.}-{0:0} , at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 2 locks held by kworker/u8:6/268: #0: ffff888100089148 ( (wq_completion)events_unbound ){+.+.}-{0:0} , at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc90001557d80 (connector_reaper_work ){+.+.}-{0:0} , at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 3 locks held by kworker/u8:10/1053: #0: ffff888100aad948 ( (wq_completion)netns ){+.+.}-{0:0} , at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc900020dfd80 (net_cleanup_work ){+.+.}-{0:0} , at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 #2: ffffffff89830850 (pernet_ops_rwsem ){++++}-{3:3} , at: cleanup_net+0xbb/0xbf0 net/core/net_namespace.c:594 2 locks held by kworker/u8:11/1223: 2 locks held by getty/2463: #0: ffff88810eb760a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 ( &ldata->atomic_read_lock ){+.+.}-{3:3} , at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 1 lock held by syz-executor.3/2533: #0: ffffffff886bfdb8 ( rcu_state.exp_mutex ){+.+.}-{3:3} , at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:323 3 locks held by kworker/1:4/4794: 6 locks held by kworker/0:3/4806: #0: ffff8881052ccd48 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc9000adffd80 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 #2: ffff88810971e190 (&dev->mutex ){....}-{3:3} , at: device_lock include/linux/device.h:1009 [inline] , at: hub_event+0x1be/0x4f50 drivers/usb/core/hub.c:5849 #3: ffff88811ee7e190 ( &dev->mutex ){....}-{3:3} , at: device_lock include/linux/device.h:1009 [inline] , at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1003 #4: ffff888111661160 (&dev->mutex ){....}-{3:3} , at: device_lock include/linux/device.h:1009 [inline] , at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1003 #5: ffffffff892e8dc8 ( input_mutex ){+.+.}-{3:3} , at: input_register_device+0xa2b/0x1140 drivers/input/input.c:2463 4 locks held by udevd/4812: #0: ffff888116d281c8 ( &p->lock ){+.+.}-{3:3} , at: seq_read_iter+0xde/0x12c0 fs/seq_file.c:182 #1: ffff888106af6888 (&of->mutex #2 ){+.+.}-{3:3} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888111bbbd28 ( kn->active #25 ){.+.+}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811ee7e190 ( &dev->mutex ){....}-{3:3} , at: device_lock_interruptible include/linux/device.h:1014 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 3 locks held by kworker/0:4/4813: 1 lock held by syz-executor.4/4881: #0: ffffffff886bfdb8 ( rcu_state.exp_mutex ){+.+.}-{3:3} , at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:323 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc2-syzkaller-00024-g5821bf2dffbe #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+0x116/0x1f0 lib/dump_stack.c:114 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:223 [inline] watchdog+0xf86/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: yealink 2-1:36.0: unexpected response 0 yealink 2-1:36.0: urb_ctl_callback - urb status -71 NMI backtrace for cpu 0 CPU: 0 PID: 2528 Comm: syz-executor.0 Not tainted 6.10.0-rc2-syzkaller-00024-g5821bf2dffbe #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:413 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 51 03 0b ff eb a0 e8 da 03 0b RSP: 0018:ffffc900000075c0 EFLAGS: 00000002 RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff829a99d5 RDI: ffffffff8d71fc60 RBP: ffffffff8d71fc20 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000004 R12: 0000000000000000 R13: 000000000000005b R14: ffffffff829a9970 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31226000 CR3: 0000000115f56000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_out drivers/tty/serial/8250/8250.h:122 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3322 [inline] serial8250_console_write+0xce7/0x1090 drivers/tty/serial/8250/8250_port.c:3393 console_emit_next_record kernel/printk/printk.c:2928 [inline] console_flush_all+0x53c/0xd70 kernel/printk/printk.c:2994 console_unlock+0xae/0x290 kernel/printk/printk.c:3063 vprintk_emit kernel/printk/printk.c:2345 [inline] vprintk_emit+0x11a/0x5a0 kernel/printk/printk.c:2300 dev_vprintk_emit drivers/base/core.c:4951 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4962 __dev_printk+0xf5/0x270 drivers/base/core.c:4974 _dev_err+0xe5/0x120 drivers/base/core.c:5017 urb_ctl_callback+0x1eb/0x2f0 drivers/input/misc/yealink.c:454 __usb_hcd_giveback_urb+0x364/0x5c0 drivers/usb/core/hcd.c:1648 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1732 dummy_timer+0x17f6/0x3900 drivers/usb/gadget/udc/dummy_hcd.c:1987 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x20c/0xcc0 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x10f/0x450 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x8b/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:stack_trace_consume_entry+0xf/0x170 kernel/stacktrace.c:83 Code: 66 00 e9 db fc ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 b8 00 00 00 00 00 fc ff df 55 <53> 48 89 fb 48 83 c7 10 48 89 fa 48 83 ec 08 48 c1 ea 03 0f b6 04 RSP: 0018:ffffc900015c7730 EFLAGS: 00000293 RAX: dffffc0000000000 RBX: ffffffff8122ebde RCX: ffffffff810dc86e RDX: ffff88810bfd8000 RSI: ffffffff8122ebde RDI: ffffc900015c7808 RBP: ffffc900015c77d8 R08: 0000000000000007 R09: 0000000000000000 R10: ffffffff8122ebde R11: 0000000000000000 R12: ffffc900015c7748 R13: ffffffff813f1150 R14: ffffc900015c7808 R15: ffff88810bfd8000 arch_stack_walk+0xe1/0x170 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 save_stack+0x162/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_page+0x696/0xd40 mm/page_alloc.c:2565 vfree+0x181/0x7a0 mm/vmalloc.c:3346 kcov_put kernel/kcov.c:429 [inline] kcov_put+0x2a/0x40 kernel/kcov.c:425 kcov_close+0x10/0x20 kernel/kcov.c:525 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa9b/0x2b20 kernel/exit.c:874 do_group_exit+0xd3/0x2a0 kernel/exit.c:1023 get_signal+0x2618/0x2710 kernel/signal.c:2909 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x141/0x250 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff942d6d901 Code: Unable to access opcode bytes at 0x7ff942d6d8d7. RSP: 002b:00007fff7a163470 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: fffffffffffffffe RBX: 000000000000000d RCX: 00007ff942d6d901 RDX: 0000000000090800 RSI: 00007ff942dca6da RDI: 00000000ffffff9c RBP: 00007fff7a16352c R08: 00000000000040c8 R09: 00007ff942e7b080 R10: 0000000000000000 R11: 0000000000000287 R12: 0000000000000000 R13: 00000000000169e8 R14: 00000000000169e8 R15: 0000000000000000