INFO: task syz.0.495:7017 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.495 state:D stack:29448 pid:7017 tgid:6984 ppid:2965 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145d/0x4a00 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776 uevent_net_broadcast_untagged lib/kobject_uevent.c:317 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline] kobject_uevent_env+0xb88/0x1920 lib/kobject_uevent.c:608 driver_register+0x2d3/0x4b0 drivers/base/driver.c:257 usb_gadget_register_driver_owner+0x132/0x330 drivers/usb/gadget/udc/core.c:1719 raw_ioctl_run drivers/usb/gadget/legacy/raw_gadget.c:596 [inline] raw_ioctl+0x17ec/0x2e60 drivers/usb/gadget/legacy/raw_gadget.c:1307 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f905f88f34b RSP: 002b:00007f905e2d3f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007f905f88f34b RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000006 RBP: 00007f905e2d4fe0 R08: 0000000000000000 R09: 00302e6364755f79 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f905e2d3fb0 R14: 0000200000000740 R15: 00007f905fc124c0 Showing all locks held in the system: 3 locks held by kworker/0:0/9: 2 locks held by kworker/0:1/10: 1 lock held by khungtaskd/30: #0: ffffffff892cd6e0 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:867 [inline] , at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:1/32: #0: ffff888100ac4948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc90000227ca0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffffffff8a6505b0 ( pernet_ops_rwsem){++++}-{4:4} , at: cleanup_net+0xad/0x900 net/core/net_namespace.c:670 #3: ffffffff892d8d00 (rcu_state.barrier_mutex ){+.+.}-{4:4} , at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3816 2 locks held by kworker/0:2/2665: 2 locks held by getty/2918: #0: ffff8881127770a0 (&tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000452f0 (&ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211 4 locks held by kworker/0:3/5216: 5 locks held by kworker/0:4/5227: 5 locks held by kworker/0:5/5334: 2 locks held by syz-executor/7019: #0: ffffffff8a6505b0 (pernet_ops_rwsem ){++++}-{4:4} , at: copy_net_ns+0x31b/0x780 net/core/net_namespace.c:577 #1: ffffffff892d8d00 (rcu_state.barrier_mutex ){+.+.}-{4:4} , at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3816 2 locks held by syz-executor/7029: #0: ffffffff8a6505b0 (pernet_ops_rwsem ){++++}-{4:4} , at: copy_net_ns+0x31b/0x780 net/core/net_namespace.c:577 #1: ffffffff892d8d00 ( rcu_state.barrier_mutex ){+.+.}-{4:4} , at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3816 1 lock held by syz-executor/7039: 2 locks held by syz-executor/7050: #0: ffffffff8a6505b0 ( pernet_ops_rwsem ){++++}-{4:4} , at: copy_net_ns+0x31b/0x780 net/core/net_namespace.c:577 #1: ffffffff892d8d00 (rcu_state.barrier_mutex ){+.+.}-{4:4} , at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3816 2 locks held by syz-executor/7052: #0: ffffffff8a6505b0 (pernet_ops_rwsem ){++++}-{4:4} , at: copy_net_ns+0x31b/0x780 net/core/net_namespace.c:577 #1: ffffffff892d8d00 (rcu_state.barrier_mutex ){+.+.}-{4:4} , at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3816 1 lock held by syz-executor/7103: #0: ffffffff892d8e38 (rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311 1 lock held by syz-executor/7110: #0: ffffffff892d8e38 (rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:160 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x133/0x180 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xe66/0x1180 kernel/hung_task.c:515 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: cdc_wdm 1-1:1.0: Stall on int endpoint NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5216 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events free_obj_work RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:246 Code: cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 77 da 22 0b <65> 8b 05 88 da 22 0b a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 RSP: 0018:ffffc900000070b0 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 0000000000000005 RCX: ffffffff87547566 RDX: ffff8881126c57c0 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffffffff885c9f80 R08: 0000000000000001 R09: 0000000000000004 R10: 0000000000000004 R11: 00000000001cd658 R12: 0000000000000004 R13: 0000000000000001 R14: 0000000000000008 R15: ffffc900000072e0 FS: 0000000000000000(0000) GS:ffff888268bf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6a53391000 CR3: 00000000090a6000 CR4: 00000000003506f0 Call Trace: __sanitizer_cov_trace_switch+0x54/0x90 kernel/kcov.c:351 vsnprintf+0x176/0x11e0 lib/vsprintf.c:2891 snprintf+0xc7/0x100 lib/vsprintf.c:3041 print_caller kernel/printk/printk.c:1366 [inline] info_print_prefix+0x134/0x350 kernel/printk/printk.c:1385 record_print_text+0x140/0x400 kernel/printk/printk.c:1432 printk_get_next_message+0x2d1/0x6d0 kernel/printk/printk.c:3018 console_emit_next_record kernel/printk/printk.c:3083 [inline] console_flush_one_record+0x684/0xc60 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 dev_vprintk_emit drivers/base/core.c:4914 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925 __dev_printk+0xf5/0x270 drivers/base/core.c:4937 _dev_err+0xe4/0x120 drivers/base/core.c:4980 wdm_int_callback+0x3dd/0xbd0 drivers/usb/class/cdc-wdm.c:270 __usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745 dummy_timer+0x1809/0x3ad0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x208/0x940 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x183/0x2d0 kernel/locking/lockdep.c:5893 Code: 0f c1 05 98 4c 47 0b 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 8d 08 47 0b 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41 RSP: 0018:ffffc9000226f638 EFLAGS: 00000206 RAX: e13e1438a386cb00 RBX: ffffffff892cd6e0 RCX: ffffc9000226f644 RDX: 0000000000000002 RSI: ffffffff88ce314f RDI: ffffffff878a7300 RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000216ba027 R10: 0000000000000002 R11: 000000000000e183 R12: ffffffff813c1194 R13: 0000000000000206 R14: ffff8881126c57c0 R15: 0000000000000003 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x43/0x70 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6668 [inline] kmem_cache_free+0x2a7/0x710 mm/slub.c:6779 free_object_list.isra.0+0xf8/0x2a0 lib/debugobjects.c:326 free_obj_work+0x19d/0x3d0 lib/debugobjects.c:513 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 cdc_wdm 1-1:1.0: wdm_int_callback - usb_submit_urb failed with result -1