INFO: task syz.7.3042:17243 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.3042 state:D stack:27616 pid:17243 tgid:17242 ppid:13640 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 device_lock include/linux/device.h:914 [inline] usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x953/0x13f0 fs/open.c:965 vfs_open+0x3b/0x340 fs/open.c:1097 do_open fs/namei.c:3975 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4134 do_filp_open+0x1fa/0x410 fs/namei.c:4161 do_sys_openat2+0x121/0x1c0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3a5b78d710 RSP: 002b:00007f3a599edb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000109301 RCX: 00007f3a5b78d710 RDX: 0000000000109301 RSI: 00007f3a599edc10 RDI: 00000000ffffff9c RBP: 00007f3a599edc10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f3a5b9e6038 R14: 00007f3a5b9e5fa0 R15: 00007ffd9ad80928 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:11/4784: #0: ffff88801b2df148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801b2df148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000e477ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000e477ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f4d9450 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:670 #3: ffffffff8e142c40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820 2 locks held by getty/5591: #0: ffff88814ddf20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/u9:2/5830: #0: ffff88807bd09948 ( (wq_completion)hci0 ){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] ){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90004cdfba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90004cdfba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff88805099cdc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 6 locks held by kworker/1:5/5877: #0: ffff888020ae4548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020ae4548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90004f2fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90004f2fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888145fc7198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888145fc7198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5893 #3: ffff88806e27c198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #3: ffff88806e27c198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006 #4: ffff8880794c3160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #4: ffff8880794c3160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006 #5: ffff8880a432c0d0 (&d->usb_mutex#2){+.+.}-{4:4}, at: rtl28xxu_ctrl_msg+0x56/0x640 drivers/media/usb/dvb-usb-v2/rtl28xxu.c:24 4 locks held by udevd/5985: #0: ffff8880592409e0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182 #1: ffff88802818b888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff888065b09788 (kn->active#22){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888065b09788 (kn->active#22){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff88806e27c198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline] #3: ffff88806e27c198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 8 locks held by kworker/0:6/7427: 4 locks held by udevd/9916: #0: ffff88805c748d58 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182 #1: ffff888029b3d888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff888048d1d698 (kn->active#22){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888048d1d698 (kn->active#22){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff88802ee67198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline] #3: ffff88802ee67198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by syz.7.3042/17243: #0: ffff88802809f198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:914 [inline] , at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 1 lock held by syz.0.3190/17775: #0: ffff88802809f198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:914 [inline] , at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 1 lock held by syz.9.3225/17998: #0: ffff88802809f198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #0: ffff88802809f198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 1 lock held by syz.1.3545/19674: #0: ffff88802809f198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #0: ffff88802809f198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:337 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:500 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 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: 7427 Comm: kworker/0:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:free_slab_obj_exts mm/slub.c:-1 [inline] RIP: 0010:unaccount_slab mm/slub.c:3187 [inline] RIP: 0010:__free_slab+0xb9/0x1a0 mm/slub.c:3287 Code: 40 08 f8 a8 01 0f 84 c4 00 00 00 40 f6 c7 02 0f 85 cc 00 00 00 48 83 e7 f8 74 0f 48 f7 43 38 04 00 00 00 75 5c e8 17 f8 fe ff <48> c7 43 38 00 00 00 00 48 8b 03 48 c1 e8 3a 48 8b 3c c5 00 25 a2 RSP: 0018:ffffc90000007bb0 EFLAGS: 00000286 RAX: 322bf8ed0a7f3000 RBX: ffffea0002a96ac0 RCX: 322bf8ed0a7f3000 RDX: 0000000000000002 RSI: ffffffff8d7f7453 RDI: ffffffff8bc0d6e0 RBP: 0000000000000000 R08: ffffffff8f9dd677 R09: 1ffffffff1f3bace R10: dffffc0000000000 R11: fffffbfff1f3bacf R12: ffffffff821b8510 R13: ffffffff81a84117 R14: ffff888140407b40 R15: ffffea0002a96ad8 FS: 0000000000000000(0000) GS:ffff888125d22000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3f02ff61b8 CR3: 0000000026f44000 CR4: 00000000003526f0 Call Trace: rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2034 [inline] RIP: 0010:vprintk_emit+0x49d/0x590 kernel/printk/printk.c:2422 Code: 0f 84 34 ff ff ff e8 92 ee 1f 00 fb eb 44 e8 8a ee 1f 00 e8 e5 93 a6 09 4d 85 f6 74 94 e8 7b ee 1f 00 fb 48 c7 c7 c0 12 13 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 1b 3b RSP: 0018:ffffc9000bb3e5a0 EFLAGS: 00000246 RAX: ffffffff81a06e35 RBX: ffffffff81a06c8e RCX: 0000000000100000 RDX: ffffc9001726c000 RSI: 00000000000fffff RDI: ffffffff8e1312c0 RBP: ffffc9000bb3e6b0 R08: ffffffff8f9dd677 R09: 1ffffffff1f3bace R10: dffffc0000000000 R11: fffffbfff1f3bacf R12: 0000000000000000 R13: 0000000000000057 R14: 0000000000000200 R15: 1ffff92001767cb8 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925 __netdev_printk+0x3d7/0x4d0 net/core/dev.c:12755 netdev_err+0x10a/0x160 net/core/dev.c:12807 asix_set_sw_mii drivers/net/usb/asix_common.c:78 [inline] asix_check_host_enable drivers/net/usb/asix_common.c:98 [inline] __asix_mdio_read drivers/net/usb/asix_common.c:484 [inline] asix_mdio_read+0x204/0x530 drivers/net/usb/asix_common.c:507 asix_phy_reset+0xbc/0x1b0 drivers/net/usb/asix_devices.c:215 ax88172_bind+0x3f0/0x5e0 drivers/net/usb/asix_devices.c:275 usbnet_probe+0xa96/0x2870 drivers/net/usb/usbnet.c:1783 usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2689 hub_port_connect drivers/usb/core/hub.c:5561 [inline] hub_port_connect_change drivers/usb/core/hub.c:5701 [inline] port_event drivers/usb/core/hub.c:5865 [inline] hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5947 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245