INFO: task syz.1.18:508 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18        state:D stack:0     pid:508   tgid:507   ppid:491    flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5345 [inline]
 __schedule+0xde4/0x1790 kernel/sched/core.c:6725
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:6817
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:6874
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x7d0/0x1240 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1040
 mutex_lock+0xe4/0x100 kernel/locking/mutex.c:286
 device_lock include/linux/device.h:999 [inline]
 usbdev_do_ioctl drivers/usb/core/devio.c:2608 [inline]
 usbdev_ioctl+0x13e/0x2120 drivers/usb/core/devio.c:2824
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0x126/0x1b0 fs/ioctl.c:892
 __x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:892
 x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f1bf919de59
RSP: 002b:00007f1bfa08b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1bf9425fa0 RCX: 00007f1bf919de59
RDX: 0000200000000000 RSI: 000000008008551c RDI: 0000000000000003
RBP: 00007f1bf9233e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1bf9426038 R14: 00007f1bf9425fa0 R15: 00007ffec37820a8
 </TASK>
INFO: task syz.0.17:513 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:0     pid:513   tgid:512   ppid:489    flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5345 [inline]
 __schedule+0xde4/0x1790 kernel/sched/core.c:6725
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:6817
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:6874
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x7d0/0x1240 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1040
 mutex_lock+0xe4/0x100 kernel/locking/mutex.c:286
 device_lock include/linux/device.h:999 [inline]
 usbdev_do_ioctl drivers/usb/core/devio.c:2608 [inline]
 usbdev_ioctl+0x13e/0x2120 drivers/usb/core/devio.c:2824
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0x126/0x1b0 fs/ioctl.c:892
 __x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:892
 x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7eff2af9de59
RSP: 002b:00007eff2beec028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007eff2b225fa0 RCX: 00007eff2af9de59
RDX: 0000200000000000 RSI: 000000008008551c RDI: 0000000000000003
RBP: 00007eff2b033e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007eff2b226038 R14: 00007eff2b225fa0 R15: 00007ffef043dfc8
 </TASK>
INFO: task syz.5.20:517 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.20        state:D stack:0     pid:517   tgid:515   ppid:493    flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5345 [inline]
 __schedule+0xde4/0x1790 kernel/sched/core.c:6725
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:6817
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:6874
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x7d0/0x1240 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1040
 mutex_lock+0xe4/0x100 kernel/locking/mutex.c:286
 device_lock include/linux/device.h:999 [inline]
 usbdev_open+0x1be/0x780 drivers/usb/core/devio.c:1051
 chrdev_open+0x4e8/0x610 fs/char_dev.c:414
 do_dentry_open+0x973/0x1400 fs/open.c:952
 vfs_open+0x3f/0x350 fs/open.c:1084
 do_open fs/namei.c:3782 [inline]
 path_openat+0x2eac/0x37f0 fs/namei.c:3941
 do_filp_open+0x1f2/0x440 fs/namei.c:3968
 do_sys_openat2+0x134/0x1d0 fs/open.c:1411
 do_sys_open fs/open.c:1426 [inline]
 __do_sys_openat fs/open.c:1442 [inline]
 __se_sys_openat fs/open.c:1437 [inline]
 __x64_sys_openat+0x13a/0x170 fs/open.c:1437
 x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fe96bf5e68e
RSP: 002b:00007fe96cef1b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe96cef26c0 RCX: 00007fe96bf5e68e
RDX: 0000000000008001 RSI: 00007fe96cef1c00 RDI: ffffffffffffff9c
RBP: 00007fe96cef1c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fe96c226038 R14: 00007fe96c225fa0 R15: 00007fff14c14c78
 </TASK>
INFO: task syz.4.19:518 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.19        state:D stack:0     pid:518   tgid:516   ppid:494    flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5345 [inline]
 __schedule+0xde4/0x1790 kernel/sched/core.c:6725
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:6817
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:6874
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x7d0/0x1240 kernel/locking/mutex.c:752
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1040
 mutex_lock+0xe4/0x100 kernel/locking/mutex.c:286
 device_lock include/linux/device.h:999 [inline]
 usbdev_open+0x1be/0x780 drivers/usb/core/devio.c:1051
 chrdev_open+0x4e8/0x610 fs/char_dev.c:414
 do_dentry_open+0x973/0x1400 fs/open.c:952
 vfs_open+0x3f/0x350 fs/open.c:1084
 do_open fs/namei.c:3782 [inline]
 path_openat+0x2eac/0x37f0 fs/namei.c:3941
 do_filp_open+0x1f2/0x440 fs/namei.c:3968
 do_sys_openat2+0x134/0x1d0 fs/open.c:1411
 do_sys_open fs/open.c:1426 [inline]
 __do_sys_openat fs/open.c:1442 [inline]
 __se_sys_openat fs/open.c:1437 [inline]
 __x64_sys_openat+0x13a/0x170 fs/open.c:1437
 x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f027155e68e
RSP: 002b:00007f02723fab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f02723fb6c0 RCX: 00007f027155e68e
RDX: 0000000000008001 RSI: 00007f02723fac00 RDI: ffffffffffffff9c
RBP: 00007f02723fac00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f0271826038 R14: 00007f0271825fa0 R15: 00007ffda92b98d8
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 2471a080cb2552f3595362b649af6d48b2731bea
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/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:223 [inline]
 watchdog+0xbe6/0xc40 kernel/hung_task.c:379
 kthread+0x2c5/0x360 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 801 Comm: syz-executor Not tainted syzkaller #0 2471a080cb2552f3595362b649af6d48b2731bea
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:kernfs_name_hash+0x1e0/0x220 fs/kernfs/dir.c:325
Code: ff ff 7f 48 21 c6 48 0f 45 d9 31 ff e8 29 01 7e ff 48 81 fb fe ff ff 7f b8 fe ff ff 7f 48 0f 42 c3 48 83 c4 08 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 cc cc cc cc cc 89 d9 80 e1 07 38 c1 0f 8c 85 fe
RSP: 0018:ffffc90002f17470 EFLAGS: 00000282
RAX: 0000000029d5ffa9 RBX: dffffc0000000000 RCX: ffff8881083c4500
RDX: 0000000000000000 RSI: 29d5ffa800000000 RDI: 0000000000000000
RBP: ffffc90002f17480 R08: ffff888100052c6f R09: 1ffff1102000a58d
R10: dffffc0000000000 R11: ffffed102000a58e R12: ffff8881327a7af0
R13: ffff8881327a7190 R14: 00f7c40aac695373 R15: ffffffff8625e58b
FS:  0000555589183500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555589196898 CR3: 000000012b7f6000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 kernfs_add_one+0x1a1/0x400 fs/kernfs/dir.c:793
 __kernfs_create_file+0x1db/0x280 fs/kernfs/file.c:1082
 sysfs_add_file_mode_ns+0x1d2/0x280 fs/sysfs/file.c:307
 create_files fs/sysfs/group.c:76 [inline]
 internal_create_group+0x66c/0xe70 fs/sysfs/group.c:180
 internal_create_groups fs/sysfs/group.c:220 [inline]
 sysfs_create_groups+0x5c/0x130 fs/sysfs/group.c:246
 device_add_groups drivers/base/core.c:2840 [inline]
 device_add_attrs+0x1b2/0x840 drivers/base/core.c:2915
 device_add+0x511/0xb50 drivers/base/core.c:3648
 netdev_register_kobject+0x172/0x320 net/core/net-sysfs.c:2139
 register_netdevice+0x111d/0x1890 net/core/dev.c:10619
 __ip_tunnel_create+0x3a1/0x4e0 net/ipv4/ip_tunnel.c:267
 ip_tunnel_init_net+0x311/0x870 net/ipv4/ip_tunnel.c:1146
 erspan_init_net+0x2d/0x40 net/ipv4/ip_gre.c:1768
 ops_init+0x20b/0x540 net/core/net_namespace.c:139
 setup_net+0x227/0x9b0 net/core/net_namespace.c:356
 copy_net_ns+0x5b4/0x900 net/core/net_namespace.c:510
 create_new_namespaces+0x388/0x5f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x531/0x920 kernel/fork.c:3347
 __do_sys_unshare kernel/fork.c:3421 [inline]
 __se_sys_unshare kernel/fork.c:3419 [inline]
 __x64_sys_unshare+0x3c/0x50 kernel/fork.c:3419
 x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7febd599f127
Code: 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe4f9adbe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007febd599f127
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007ffe4f9adc40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffe4f9adc48
R13: 0000000000000002 R14: 00007ffe4f9ade28 R15: 0000000000000000
 </TASK>