INFO: task udevd:16301 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:24536 pid:16301 tgid:16301 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: 0033:0x7f75786d6b6a RSP: 002b:00007ffdca692de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000560d6860b6f0 RCX: 00007f75786d6b6a RDX: 0000000000001000 RSI: 0000560d68665fa0 RDI: 0000000000000008 RBP: 0000560d6860b6f0 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffdca6932c8 R15: 000000000000000a INFO: task udevd:16301 is blocked on a mutex likely owned by task kworker/1:0:23. task:kworker/1:0 state:R running task stack:21480 pid:23 tgid:23 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event 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_hrtimeout_range_clock+0x217/0x320 kernel/time/sleep_timeout.c:216 Showing all locks held in the system: 6 locks held by kworker/0:0/9: #0: ffff888106695d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000009fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810bb07198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #2: ffff88810bb07198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5863 #3: ffff88810bb1a508 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] #3: ffff88810bb1a508 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5432 [inline] #3: ffff88810bb1a508 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5675 [inline] #3: ffff88810bb1a508 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5835 [inline] #3: ffff88810bb1a508 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x29da/0x5030 drivers/usb/core/hub.c:5917 #4: ffff8881073b1a68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5433 [inline] #4: ffff8881073b1a68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5675 [inline] #4: ffff8881073b1a68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5835 [inline] #4: ffff8881073b1a68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2a00/0x5030 drivers/usb/core/hub.c:5917 #5: ffffffff89bee090 (ehci_cf_port_reset_rwsem){.+.+}-{4:4} , at: hub_port_reset+0x1a1/0x1e00 drivers/usb/core/hub.c:3035 6 locks held by kworker/1:0/23: 1 lock held by khungtaskd/30: #0: ffffffff890c1a00 (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 2 locks held by getty/2898: #0: ffff8881122d40a0 (&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 5 locks held by kworker/1:6/5485: #0: ffff888106695d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90002b67d18 ((work_completion)(&hub->events)){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810b797198 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] ){....}-{4:4}, at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5863 #3: ffff88812137c198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:922 [inline] , at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1005 #4: ffff88811282e160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff88811282e160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1005 4 locks held by udevd/15462: #0: ffff88811d5452f0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff88810d7cb888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88810e7a43c8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88812137c198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #3: ffff88812137c198 (&dev->mutex){....}-{4:4}, at: uevent_show+0x187/0x3b0 drivers/base/core.c:2730 4 locks held by udevd/15498: #0: ffff88811b04e668 ( &p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff888111970088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881121d1788 (kn->active#23){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888121378198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:927 [inline] ffff888121378198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/16301: #0: ffff8881165bb668 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff88810dfe5488 (&of->mutex#2){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888115711968 (kn->active#5 ){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810cf3e198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:922 [inline] , at: uevent_show+0x187/0x3b0 drivers/base/core.c:2730 5 locks held by kworker/1:2/18544: #0: ffff888106695d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000ccc7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810bb1f198 (&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: ffff888121378198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:922 [inline] , at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1005 #4: ffff88811a188160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff88811a188160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1005 ============================================= 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: 23 Comm: kworker/1:0 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:dummy_timer+0x270/0x3a20 drivers/usb/gadget/udc/dummy_hcd.c:1832 Code: 00 48 83 c5 10 48 c1 e2 04 89 de 49 83 c4 78 4c 29 fa 41 80 a4 d6 b0 00 00 00 fb e8 4a de 94 fc 83 fb 19 74 2b e8 00 e3 94 fc <4c> 63 fb 49 83 ff 18 0f 87 14 2b 00 00 48 89 ea 48 c1 ea 03 42 80 RSP: 0018:ffffc900001a8be8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000006 RCX: ffffffff84e76656 RDX: ffff888101ed57c0 RSI: ffffffff84e76660 RDI: 0000000000000005 RBP: ffffffff87d530e0 R08: 0000000000000005 R09: 0000000000000019 R10: 0000000000000006 R11: 0000000000000000 R12: ffff88810afd0380 R13: dffffc0000000000 R14: ffff88810afd0000 R15: 0000000000000005 FS: 0000000000000000(0000) GS:ffff8882692d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000338000 CR3: 0000000117468000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __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:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x567/0x6d0 kernel/printk/printk.c:2449 Code: 00 4d 85 ed 0f 85 19 01 00 00 e8 74 dd 1f 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 d2 d8 1f 00 48 85 ed 0f 85 25 01 00 00 54 dd 1f 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc9000018ea38 EFLAGS: 00000246 RAX: 0000000000100000 RBX: 0000000000000057 RCX: ffffc900118ea000 RDX: 0000000000100000 RSI: ffffffff815c6d26 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000031d49 R13: 0000000000000200 R14: ffff8881022857c0 R15: ffffc9000018eb00 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