INFO: task udevd:5201 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:5201 tgid:5201 ppid:2841 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: 0033:0x7fcedec8eb6a RSP: 002b:00007ffcc5338ae8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000562cc18d8c90 RCX: 00007fcedec8eb6a RDX: 0000000000001000 RSI: 0000562cc19923b0 RDI: 0000000000000008 RBP: 0000562cc18d8c90 R08: 0000000000000008 R09: 0000000000000004 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffcc5338fc8 R15: 000000000000000a INFO: task udevd:5201 is blocked on a mutex likely owned by task kworker/0:3:5212. task:kworker/0:3 state:R running task stack:21496 pid:5212 tgid:5212 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 Showing all locks held in the system: 7 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 3 locks held by kworker/1:2/1116: 6 locks held by kworker/0:2/2606: #0: ffff8881066b3948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90003f0fd18 ((work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810b750198 (&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: ffff88810b753508 (&port_dev->status_lock ){+.+.}-{4:4} , at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] , at: hub_port_connect drivers/usb/core/hub.c:5432 [inline] , at: hub_port_connect_change drivers/usb/core/hub.c:5675 [inline] , at: port_event drivers/usb/core/hub.c:5835 [inline] , at: hub_event+0x29da/0x5030 drivers/usb/core/hub.c:5917 #4: ffff8881083e5f68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5433 [inline] ffff8881083e5f68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5675 [inline] ffff8881083e5f68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5835 [inline] ffff8881083e5f68 (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: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline] ){.+.+}-{4:4}, at: try_to_wake_up+0xb3/0x13f0 kernel/sched/core.c:4212 1 lock held by acpid/2825: #0: ffffffff890ccf38 ( rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x280/0x3c0 kernel/rcu/tree_exp.h:304 2 locks held by getty/2899: #0: ffff88811209c0a0 (&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/5194: #0: ffff88811f16d668 (&p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff88811493e888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881189a74b8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811db38198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] (&dev->mutex){....}-{4:4}, at: uevent_show+0x187/0x3b0 drivers/base/core.c:2730 4 locks held by udevd/5201: #0: ffff88811ea12540 (&p->lock ){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff888134488888 (&of->mutex#2){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888106b0b2d8 ( kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888111cce198 (&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 7 locks held by kworker/0:3/5212: 2 locks held by kworker/1:3/5232: 4 locks held by udevd/5346: #0: ffff88810f2c1e80 (&p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x12b0 fs/seq_file.c:182 #1: ffff88810c777888 ( &of->mutex#2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881083f10f8 (kn->active#5){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810b750198 ( &dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] &dev->mutex){....}-{4:4}, at: uevent_show+0x187/0x3b0 drivers/base/core.c:2730 1 lock held by syz.3.517/6919: #0: ffffffff890ccf38 (rcu_state.exp_mutex ){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336 ============================================= NMI backtrace for cpu 1 CPU: 1 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5212 Comm: kworker/0:3 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:__lock_is_held kernel/locking/lockdep.c:5596 [inline] RIP: 0010:lock_is_held_type+0x8b/0x150 kernel/locking/lockdep.c:5938 Code: ac 24 b0 0a 00 00 45 31 ff e8 a1 16 00 00 65 ff 05 a2 94 42 05 41 8b 84 24 a8 0a 00 00 85 c0 7f 17 e9 92 00 00 00 41 83 c7 01 <45> 3b bc 24 a8 0a 00 00 0f 8d 80 00 00 00 49 63 c7 48 89 ee 48 8d RSP: 0018:ffffc90000007a28 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffff888102f90b78 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff890c1a00 RDI: ffff888102f90b78 RBP: ffffffff890c1a00 R08: 0eb1c910fdb9f268 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000000 R12: ffff888102f90000 R13: ffff888102f90ab0 R14: 00000000ffffffff R15: 0000000000000006 FS: 0000000000000000(0000) GS:ffff8882691d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcede79ebb0 CR3: 0000000117e92000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: select_idle_cpu kernel/sched/fair.c:7705 [inline] select_idle_sibling kernel/sched/fair.c:7940 [inline] select_task_rq_fair+0x1f4a/0x3eb0 kernel/sched/fair.c:8639 select_task_rq kernel/sched/core.c:3583 [inline] try_to_wake_up+0x51f/0x13f0 kernel/sched/core.c:4313 call_timer_fn+0x197/0x620 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers+0x6ef/0x960 kernel/time/timer.c:2414 __run_timer_base kernel/time/timer.c:2426 [inline] __run_timer_base kernel/time/timer.c:2418 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2435 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2445 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:ffffc9000223ea38 EFLAGS: 00000246 RAX: 0000000000100000 RBX: 0000000000000057 RCX: ffffc9000fcf9000 RDX: 0000000000100000 RSI: ffffffff815c6d26 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000447d49 R13: 0000000000000200 R14: ffff8881022857c0 R15: ffffc9000223eb00 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