INFO: task syz.8.2378:7614 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.2378      state:D stack:0     pid:7614  tgid:7613  ppid:6873   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 super_lock+0x150/0x300 fs/super.c:115
 super_lock_shared fs/super.c:140 [inline]
 iterate_supers+0x8a/0x560 fs/super.c:934
 ksys_sync+0x95/0x160 fs/sync.c:103
 __ia32_sys_sync+0x12/0x20 fs/sync.c:114
 x64_sys_call+0x2a58/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:163
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fd4ad38ebe9
RSP: 002b:00007fd4ae2ca038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fd4ad5c5fa0 RCX: 00007fd4ad38ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd4ad5c5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd4ad5c6038 R14: 00007fd4ad5c5fa0 R15: 00007ffd5cbbc418
 </TASK>
INFO: task syz.8.2378:7615 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.2378      state:D stack:0     pid:7615  tgid:7613  ppid:6873   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 __schedule_loop kernel/sched/core.c:7872 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7887
 super_lock+0x150/0x300 fs/super.c:115
 super_lock_shared fs/super.c:140 [inline]
 iterate_supers+0x8a/0x560 fs/super.c:934
 ksys_sync+0x95/0x160 fs/sync.c:103
 __ia32_sys_sync+0x12/0x20 fs/sync.c:114
 x64_sys_call+0x2a58/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:163
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fd4ad38ebe9
RSP: 002b:00007fd4ae2a9038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fd4ad5c6090 RCX: 00007fd4ad38ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd4ad5c6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd4ad5c6128 R14: 00007fd4ad5c6090 R15: 00007ffd5cbbc418
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 e0010524de270d562e17ec59754923f7dbe680d3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xd8f/0xed0 kernel/hung_task.c:423
 kthread+0x2c7/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 527 Comm: kworker/1:3 Not tainted syzkaller #0 e0010524de270d562e17ec59754923f7dbe680d3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:__list_add_valid_or_report+0x0/0xf0 lib/list_debug.c:24
Code: 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 d7 4f e0 02 cc e8 c1 fd dd 02 cc b8 0a c9 56 36 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 85 f6 0f 84
RSP: 0018:ffffc900002308a0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff888115d2ba00 RCX: dffffc0000000000
RDX: ffff888115d2ba00 RSI: ffff8881f6f506e8 RDI: ffff88812199a700
RBP: ffffc90000230910 R08: 0000000000000002 R09: 0000000000000002
R10: 000000000000026c R11: 00000000000000aa R12: ffff8881f6f506e8
R13: 1ffff1103edea0dd R14: ffff8881f6f4fbc0 R15: ffff88812199a6c0
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffd09b0d58 CR3: 0000000142174000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 enqueue_task_fair+0x3fb/0x17e0 kernel/sched/fair.c:7185
 enqueue_task+0x7dc/0x11f0 kernel/sched/core.c:2104
 __activate_task kernel/sched/core.c:2151 [inline]
 activate_task+0x38b/0x3d0 kernel/sched/core.c:2185
 ttwu_do_activate+0x154/0x630 kernel/sched/core.c:4209
 ttwu_queue kernel/sched/core.c:4506 [inline]
 try_to_wake_up+0xd87/0x1b00 kernel/sched/core.c:4845
 wake_up_process+0x14/0x20 kernel/sched/core.c:4980
 hrtimer_wakeup+0x52/0x70 kernel/time/hrtimer.c:1989
 __run_hrtimer kernel/time/hrtimer.c:1753 [inline]
 __hrtimer_run_queues+0x3bd/0x9e0 kernel/time/hrtimer.c:1817
 hrtimer_interrupt+0x37e/0xf00 kernel/time/hrtimer.c:1879
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x8e/0x2b0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x7d/0x90 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2076 [inline]
RIP: 0010:vprintk_emit+0x530/0x640 kernel/printk/printk.c:2462
Code: 81 e6 00 02 00 00 31 ff e8 0d 21 1e 00 48 81 e3 00 02 00 00 75 07 e8 1f 1c 1e 00 eb 06 e8 18 1c 1e 00 fb c6 05 00 73 31 07 00 <e9> 42 fd ff ff e8 06 1c 1e 00 e9 a5 fe ff ff 41 ff ce bf 58 89 41
RSP: 0018:ffffc9000d0df440 EFLAGS: 00000283
RAX: ffffffff8167c7f8 RBX: 0000000000000200 RCX: 0000000000100000
RDX: ffffc9000c2dc000 RSI: 000000000003148b RDI: 000000000003148c
RBP: ffffc9000d0df510 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001a1be78 R12: 1ffff92001a1be8c
R13: 000000000000002c R14: 0000000000000000 R15: dffffc0000000000
 dev_vprintk_emit+0x33b/0x400 drivers/base/core.c:4962
 dev_printk_emit+0xe1/0x130 drivers/base/core.c:4973
 __dev_printk+0x17f/0x1b0 drivers/base/core.c:4985
 _dev_err+0x10b/0x160 drivers/base/core.c:5028
 hub_port_init+0x1297/0x27b0 drivers/usb/core/hub.c:-1
 hub_port_connect drivers/usb/core/hub.c:5490 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5701 [inline]
 port_event drivers/usb/core/hub.c:5865 [inline]
 hub_event+0x232d/0x4270 drivers/usb/core/hub.c:5947
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d5/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
 kthread+0x2c7/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>