INFO: task syz.5.978:9247 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.978 state:D stack:26880 pid:9247 tgid:9246 ppid:8906 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
super_lock+0x1e0/0x3d0 fs/super.c:116
__iterate_supers+0x126/0x250 fs/super.c:926
quota_sync_all fs/quota/quota.c:69 [inline]
__do_sys_quotactl fs/quota/quota.c:938 [inline]
__se_sys_quotactl+0x3a7/0x9e0 fs/quota/quota.c:917
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff1fb4dc819
RSP: 002b:00007ff1f9736028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007ff1fb755fa0 RCX: 00007ff1fb4dc819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007ff1fb572c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff1fb756038 R14: 00007ff1fb755fa0 R15: 00007ffe4b9474d8
INFO: task syz.5.978:9249 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.978 state:D stack:27880 pid:9249 tgid:9246 ppid:8906 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x169e/0x54f0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
super_lock+0x1e0/0x3d0 fs/super.c:116
__iterate_supers+0x126/0x250 fs/super.c:926
quota_sync_all fs/quota/quota.c:69 [inline]
__do_sys_quotactl fs/quota/quota.c:938 [inline]
__se_sys_quotactl+0x3a7/0x9e0 fs/quota/quota.c:917
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff1fb4dc819
RSP: 002b:00007ff1f9715028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007ff1fb756090 RCX: 00007ff1fb4dc819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007ff1fb572c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff1fb756128 R14: 00007ff1fb756090 R15: 00007ffe4b9474d8
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e3c8100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by getty/5586:
#0: ffff8880377dc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
6 locks held by kworker/1:5/5899:
#0: ffff88801aff2138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284
#1: ffffc90005527c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285
#2: ffff88802afa6210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802afa6210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899
#3: ffff8880319b0210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff8880319b0210 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xde/0x970 drivers/usb/core/hub.c:2336
#4: ffff888060bb41d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff888060bb41d8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline]
#4: ffff888060bb41d8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870 drivers/base/dd.c:1372
#5: ffffffff8f205918 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#5: ffffffff8f205918 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x2fa/0x610 drivers/input/input.c:2204
5 locks held by kworker/0:8/5945:
#0: ffff88801aff2138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3284
#1: ffffc90005797c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3285
#2: ffff88802adf6210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802adf6210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899
#3: ffff88802a0b8210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff88802a0b8210 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#4: ffff88801b340318 (&(&priv->bus_notifier)->rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:379
4 locks held by udevd/6102:
#0: ffff888037a91950 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb8/0xe20 fs/seq_file.c:183
#1: ffff88805272e478 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff888029325968 (kn->active#24){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888029325968 (kn->active#24){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff88802a0b8210 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
#3: ffff88802a0b8210 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by udevd/8193:
#0: ffff88802a1971e8 (kn->active#5){.+.+}-{0:0}, at: kernfs_fop_open+0x5a/0xcb0 fs/kernfs/file.c:619
#1: ffff88801c2d40d8 (&kernfs_locks->open_file_mutex[count]){+.+.}-{4:4}, at: kernfs_open_file_mutex_lock fs/kernfs/file.c:56 [inline]
#1: ffff88801c2d40d8 (&kernfs_locks->open_file_mutex[count]){+.+.}-{4:4}, at: kernfs_get_open_node fs/kernfs/file.c:538 [inline]
#1: ffff88801c2d40d8 (&kernfs_locks->open_file_mutex[count]){+.+.}-{4:4}, at: kernfs_fop_open+0x6e6/0xcb0 fs/kernfs/file.c:718
#2: ffffffff8e50c1b0 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
#2: ffffffff8e50c1b0 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:294
1 lock held by syz.3.792/8630:
#0: ffff888035c220d0 (&type->s_umount_key#87/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
1 lock held by syz.6.1578/11605:
#0: ffffffff8e3ce2f0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5899 Comm: kworker/1:5 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:__bfs kernel/locking/lockdep.c:1817 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1862 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2798 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3171 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3286 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3910 [inline]
RIP: 0010:__lock_acquire+0x197b/0x2cf0 kernel/locking/lockdep.c:5239
Code: 14 25 ff 0f 00 00 39 05 0f da 22 12 73 06 89 05 07 da 22 12 48 8b 02 48 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 18 fe ff ff 48 89 fb 48 c7 c7 10 54 29
RSP: 0018:ffffc90005526a60 EFLAGS: 00000002
RAX: ffffffff9657f4f8 RBX: 0000000000000145 RCX: 0000000000000007
RDX: ffffffff964760c8 RSI: ffff888020fe4b58 RDI: 0000000000000145
RBP: 88ef6dd91f32e329 R08: ffffc90005526a28 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff81a12ed0 R12: ffffffff964883b8
R13: ffffffff936500b8 R14: ffff888020fe3d80 R15: 0000000000000006
FS: 0000000000000000(0000) GS:ffff888125b62000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2cca26 CR3: 0000000073774000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
debug_object_activate+0x72/0x520 lib/debugobjects.c:835
debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline]
debug_activate kernel/time/hrtimer.c:528 [inline]
remove_and_enqueue_same_base kernel/time/hrtimer.c:1259 [inline]
__hrtimer_start_range_ns kernel/time/hrtimer.c:1396 [inline]
hrtimer_start_range_ns+0x57c/0xef0 kernel/time/hrtimer.c:1491
hrtimer_start include/linux/hrtimer.h:220 [inline]
hrtick_cond_restart kernel/sched/core.c:924 [inline]
hrtick_schedule_exit kernel/sched/core.c:986 [inline]
finish_lock_switch kernel/sched/core.c:5123 [inline]
finish_task_switch+0x3cd/0xbe0 kernel/sched/core.c:5242
context_switch kernel/sched/core.c:5390 [inline]
__schedule+0x16a6/0x54f0 kernel/sched/core.c:7188
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7512
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
irqentry_exit+0x14f/0x730 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5874
Code: ff ff ff e8 b1 d2 a0 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 8b 1d 1b 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 28 b2 31
RSP: 0018:ffffc90005527120 EFLAGS: 00000282
RAX: a90e583933ccab00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000001574d3fb RSI: ffffffff8dbfd739 RDI: ffffffff8bca5b60
RBP: ffffffff82686c0c R08: ffffffff82686c0c R09: ffffffff8e3c8100
R10: dffffc0000000000 R11: fffffbfff1f9e8ff R12: 0000000000000002
R13: ffffffff8e3c8100 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:838 [inline]
class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
kernfs_root+0x38/0x230 fs/kernfs/kernfs-internal.h:74
kernfs_clear_inode_nlink fs/kernfs/dir.c:1523 [inline]
__kernfs_remove+0x503/0x8e0 fs/kernfs/dir.c:1592
kernfs_remove_by_name_ns+0xc0/0x140 fs/kernfs/dir.c:1798
kernfs_remove_by_name include/linux/kernfs.h:639 [inline]
sysfs_unmerge_group+0xd4/0x140 fs/sysfs/group.c:408
rpm_sysfs_remove drivers/base/power/sysfs.c:823 [inline]
dpm_sysfs_remove+0x76/0xd0 drivers/base/power/sysfs.c:832
device_del+0x250/0x900 drivers/base/core.c:3870
cdev_device_del+0x27/0xf0 fs/char_dev.c:577
evdev_disconnect+0x4c/0xb0 drivers/input/evdev.c:1403
__input_unregister_device+0x378/0x610 drivers/input/input.c:2206
input_unregister_device+0x9b/0x100 drivers/input/input.c:2435
cm109_usb_disconnect+0x65/0x1b0 drivers/input/misc/cm109.c:673
usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:621 [inline]
__device_release_driver drivers/base/dd.c:1352 [inline]
device_release_driver_internal+0x4d9/0x870 drivers/base/dd.c:1375
bus_remove_device+0x45a/0x570 drivers/base/bus.c:657
device_del+0x52b/0x900 drivers/base/core.c:3895
usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1478
usb_disconnect+0x315/0x970 drivers/usb/core/hub.c:2345
hub_port_connect drivers/usb/core/hub.c:5407 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x1cf9/0x4f60 drivers/usb/core/hub.c:5953
process_one_work+0x9a3/0x1710 kernel/workqueue.c:3312
process_scheduled_works kernel/workqueue.c:3403 [inline]
worker_thread+0xba8/0x11e0 kernel/workqueue.c:3489
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245