INFO: task syz.2.1443:11504 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1443 state:D stack:28104 pid:11504 tgid:11503 ppid:5834 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5254 [inline] __schedule+0x17c4/0x4d60 kernel/sched/core.c:6862 __schedule_loop kernel/sched/core.c:6944 [inline] schedule+0x165/0x360 kernel/sched/core.c:6959 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7016 __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: 0033:0x7f3562b8d810 RSP: 002b:00007f3563af5b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f3562b8d810 RDX: 0000000000000002 RSI: 00007f3563af5c10 RDI: 00000000ffffff9c RBP: 00007f3563af5c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f3562de6038 R14: 00007f3562de5fa0 R15: 00007ffeee6cf9c8 Showing all locks held in the system: 2 locks held by kworker/0:0/9: #0: ffff8880b863a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:638 #1: ffff8880b8624048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 6 locks held by kworker/0:1/10: #0: ffff888020a83948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020a83948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc900000f7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900000f7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888028484198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888028484198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5893 #3: ffff888032c91198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #3: ffff888032c91198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006 #4: ffff888077f07160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #4: ffff888077f07160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006 #5: ffff8880272cca68 (hcd->bandwidth_mutex){+.+.}-{4:4}, at: usb_set_interface+0x353/0x13f0 drivers/usb/core/message.c:1564 1 lock held by khungtaskd/31: #0: ffffffff8e13d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by pvrusb2-context/2344: #0: ffff888066910188 (&hdw->big_lock_mutex){+.+.}-{4:4}, at: pvr2_hdw_initialize+0xc6/0x3ac0 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2326 #1: ffffffff8dfe2a70 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xf0/0x2b0 kernel/umh.c:214 2 locks held by getty/5590: #0: ffff88814dc3f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by udevd/5825: #0: ffff8880663f0d58 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182 #1: ffff88805c9bb888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff888026214008 (kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888026214008 (kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff8880320e5198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline] #3: ffff8880320e5198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 3 locks held by kworker/1:4/5914: #0: ffff888020a83948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020a83948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90004897ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90004897ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff8881447f0198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff8881447f0198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5893 6 locks held by kworker/1:6/5921: #0: ffff888020a83948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020a83948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc900048e7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900048e7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5893 #3: ffff8880320e5198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #3: ffff8880320e5198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x950 drivers/usb/core/hub.c:2330 #4: ffff8880217d5160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #4: ffff8880217d5160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline] #4: ffff8880217d5160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1294 #5: ffff888066910188 (&hdw->big_lock_mutex){+.+.}-{4:4}, at: pvr2_hdw_disconnect+0x6d/0x500 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2710 4 locks held by udevd/6127: #0: ffff8880426f9b08 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182 #1: ffff88805ccdd888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff8880630023c8 (kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880630023c8 (kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff888032c91198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline] #3: ffff888032c91198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by syz.2.1443/11504: #0: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #0: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 1 lock held by syz.6.1532/11826: #0: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #0: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 1 lock held by syz.8.1653/12219: #0: ffff8881447f8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #0: ffff8881447f8198 (&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: 5813 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:212 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 90 ed e1 09 cc f3 0f 1e fa 89 f6 31 d2 e9 02 ff 59 03 66 RSP: 0018:ffffc90000007db0 EFLAGS: 00000046 RAX: 0000000000001da6 RBX: ffff8880b8623900 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 0000000000001da6 RDI: 0000000000000838 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff81ae72e5 R10: 0000000000000003 R11: ffffffff81712900 R12: 0000000010003fc0 R13: dffffc0000000000 R14: 0000000000001da6 R15: 0000000000000020 FS: 000055555b988500(0000) GS:ffff888125ce4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f48aa79cd58 CR3: 000000007c974000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:409 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:416 clockevents_program_event+0x1cf/0x360 kernel/time/clockevents.c:334 hrtimer_update_softirq_timer kernel/time/hrtimer.c:1207 [inline] hrtimer_run_softirq+0x23f/0x2b0 kernel/time/hrtimer.c:1861 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:cred_label security/apparmor/include/cred.h:27 [inline] RIP: 0010:aa_cred_raw_label security/apparmor/include/cred.h:49 [inline] RIP: 0010:aa_current_raw_label security/apparmor/include/cred.h:96 [inline] RIP: 0010:__begin_current_label_crit_section security/apparmor/include/cred.h:160 [inline] RIP: 0010:common_file_perm+0xf1/0x230 security/apparmor/lsm.c:533 Code: 4c 63 2d 72 2a 61 09 4c 03 2b 0f 84 00 01 00 00 e8 64 9d 79 fd 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 ef e8 55 47 df fd 4d 8b 6d 00 4d 85 ed 48 89 6c 24 10 RSP: 0018:ffffc90003e9fbe0 EFLAGS: 00000246 RAX: 1ffff110049dd5c2 RBX: ffff88802bf69880 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffff88807c90ae00 RDI: ffffffff8bb8afa0 RBP: ffff88807c90ae00 R08: ffff88802f2561c3 R09: 1ffff11005e4ac38 R10: dffffc0000000000 R11: ffffed1005e4ac39 R12: ffff888031fb2730 R13: ffff888024eeae10 R14: 0000000000000004 R15: 1ffff110063f64e6 security_file_permission+0x91/0x290 security/security.c:2913 rw_verify_area+0xbb/0x4d0 fs/read_write.c:473 vfs_read+0x154/0xa30 fs/read_write.c:563 ksys_read+0x145/0x250 fs/read_write.c:715 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: 0033:0x7f7ae4d8d99d Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb bd e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d c1 ab 22 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec RSP: 002b:00007ffd723b45a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7ae4d8d99d RDX: 0000000000000004 RSI: 00007ffd723b45bc RDI: 0000000000000003 RBP: 0000000000000000 R08: 7fffffffffffffff R09: 3fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd723b49d0 R13: 0000000000000004 R14: 00007ffd723b45bc R15: 00007ffd723b4650