INFO: task udevd:5252 blocked for more than 143 seconds. Not tainted 6.15.0-rc1-syzkaller-00082-gf41f7b3d9daf #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24728 pid:5252 tgid:5252 ppid:2840 task_flags:0x400140 flags:0x00004002 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 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746 device_lock include/linux/device.h:922 [inline] uevent_show+0x187/0x3b0 drivers/base/core.c:2730 dev_attr_show+0x53/0xe0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x213/0x3e0 fs/sysfs/file.c:65 seq_read_iter+0x506/0x12b0 fs/seq_file.c:230 kernfs_fop_read_iter+0x422/0x5a0 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x8c8/0xc70 fs/read_write.c:570 ksys_read+0x12a/0x240 fs/read_write.c:713 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: 0033:0x7fb2522fdb6a RSP: 002b:00007ffe4616a668 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055aaf5bd5a80 RCX: 00007fb2522fdb6a RDX: 0000000000001000 RSI: 000055aaf5c52700 RDI: 0000000000000008 RBP: 000055aaf5bd5a80 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffe4616ab48 R15: 000000000000000a INFO: task udevd:5252 is blocked on a mutex likely owned by task kworker/1:1:38. task:kworker/1:1 state:R running task stack:22056 pid:38 tgid:38 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff890c1a00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] ffffffff890c1a00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] ffffffff890c1a00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 7 locks held by kworker/1:1/38: 5 locks held by kworker/1:2/1114: #0: ffff888100080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900019ffd18 ((work_completion)(&intf->reset_ws)){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88811ac3f198 (&dev->mutex){....}-{4:4}, at: device_trylock include/linux/device.h:932 [inline] ffff88811ac3f198 (&dev->mutex){....}-{4:4}, at: usb_lock_device_for_reset+0x184/0x330 drivers/usb/core/usb.c:904 #3: ffff88810affe508 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] (&port_dev->status_lock){+.+.}-{4:4}, at: usb_reset_device+0x559/0xa90 drivers/usb/core/hub.c:6361 #4: ffff888107f4ab68 (hcd->address0_mutex){+.+.}-{4:4} , at: usb_reset_and_verify_device+0x335/0x1120 drivers/usb/core/hub.c:6167 3 locks held by kworker/0:2/2691: 2 locks held by getty/2900: #0: ffff88811219f0a0 ( &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 4 locks held by udevd/5252: #0: ffff888113db5b08 (&p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff888114f5ec88 (&of->mutex #2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88810f3b25a8 (kn->active #5 ){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888118aeb198 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] ){....}-{4:4}, at: uevent_show+0x187/0x3b0 drivers/base/core.c:2730 4 locks held by kworker/1:5/5349: #0: ffff8881066b3948 ( (wq_completion)usb_hub_wq){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90002397d18 ((work_completion)(&hub->events)){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810affb198 (&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: ffff88810affe508 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x5c3/0x5030 drivers/usb/core/hub.c:5916 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.15.0-rc1-syzkaller-00082-gf41f7b3d9daf #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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+0x11c4/0x15d0 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: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: kworker/1:1 Not tainted 6.15.0-rc1-syzkaller-00082-gf41f7b3d9daf #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x20 kernel/kcov.c:300 Code: bf 06 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <40> 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 86 fe ff ff 66 0f 1f 44 RSP: 0018:ffffc90000286298 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffffffff8748ff44 RCX: ffffffff871f2288 RDX: 0000000000000004 RSI: 000000000000005d RDI: 0000000000000000 RBP: ffffc90000286340 R08: 0000000000000001 R09: 0000000000000003 R10: 0000000000000005 R11: 0000000000163354 R12: 000000000000005d R13: ffffffff8748ff44 R14: ffffc900002863c0 R15: 000000000000005d FS: 0000000000000000(0000) GS:ffff8882692d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555608674a8 CR3: 0000000116114000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: format_decode+0x128/0xd40 lib/vsprintf.c:2597 vsnprintf+0x156/0x1160 lib/vsprintf.c:2795 sprintf+0xcc/0x100 lib/vsprintf.c:3015 print_caller kernel/printk/printk.c:1392 [inline] info_print_prefix+0x146/0x350 kernel/printk/printk.c:1409 record_print_text+0x140/0x400 kernel/printk/printk.c:1456 printk_get_next_message+0x2d1/0x6d0 kernel/printk/printk.c:3024 console_emit_next_record kernel/printk/printk.c:3092 [inline] console_flush_all+0x6ea/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:4891 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4902 __netdev_printk+0x1fb/0x500 net/core/dev.c:12401 netdev_err+0xe4/0x120 net/core/dev.c:12453 asix_set_sw_mii drivers/net/usb/asix_common.c:78 [inline] asix_check_host_enable+0x18f/0x240 drivers/net/usb/asix_common.c:98 __asix_mdio_read+0x9c/0x260 drivers/net/usb/asix_common.c:506 asix_phy_reset+0x106/0x1f0 drivers/net/usb/asix_devices.c:215 ax88172_bind+0x41f/0x5d0 drivers/net/usb/asix_devices.c:275 usbnet_probe+0xab8/0x27a0 drivers/net/usb/usbnet.c:1772 usb_probe_interface+0x300/0x9c0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:658 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1030 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3666 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:658 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1030 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3666 usb_new_device+0xd07/0x1a20 drivers/usb/core/hub.c:2663 hub_port_connect drivers/usb/core/hub.c:5535 [inline] hub_port_connect_change drivers/usb/core/hub.c:5675 [inline] port_event drivers/usb/core/hub.c:5835 [inline] hub_event+0x2f85/0x5030 drivers/usb/core/hub.c:5917 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 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