syzbot


INFO: task hung in hci_register_dev (2)

Status: upstream: reported syz repro on 2025/12/27 03:45
Subsystems: usb
[Documentation on labels]
Reported-by: syzbot+f201a5d7faf69008864d@syzkaller.appspotmail.com
First crash: 6d08h, last: 6d08h
Cause bisection: failed (error log, bisect log)
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [usb?] INFO: task hung in hci_register_dev (2) 0 (1) 2025/12/27 03:45
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in hci_register_dev kernel 1 1 567d 567d 0/29 auto-obsoleted due to no activity on 2024/09/10 15:35

Sample crash report:
INFO: task syz-executor:6980 blocked for more than 164 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:28520 pid:6980  tgid:6980  ppid:1      task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 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
 get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
 device_add+0xc13/0x1980 drivers/base/core.c:3613
 hci_register_dev+0x328/0xce0 net/bluetooth/hci_core.c:2621
 __vhci_create_device+0x357/0x880 drivers/bluetooth/hci_vhci.c:451
 vhci_create_device drivers/bluetooth/hci_vhci.c:479 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 vhci_write+0x2c0/0x480 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdac098e1c0
RSP: 002b:00007fffa8e51048 EFLAGS: 00000202
 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fdac098e1c0
RDX: 0000000000000002 RSI: 00007fffa8e5105a RDI: 00000000000000ca
RBP: 00007fffa8e51120 R08: 0000000000000000 R09: 00007fdac171d6c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 00007fffa8e51128 R14: 00007fffa8e513a8 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:6983 blocked for more than 164 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:27608 pid:6983  tgid:6983  ppid:1      task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 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
 get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
 device_add+0xc13/0x1980 drivers/base/core.c:3613
 hci_register_dev+0x328/0xce0 net/bluetooth/hci_core.c:2621
 __vhci_create_device+0x357/0x880 drivers/bluetooth/hci_vhci.c:451
 vhci_create_device drivers/bluetooth/hci_vhci.c:479 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 vhci_write+0x2c0/0x480 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f801418e1c0
RSP: 002b:00007fff6963a2f8 EFLAGS: 00000202
 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f801418e1c0
RDX: 0000000000000002 RSI: 00007fff6963a30a RDI: 00000000000000ca
RBP: 00007fff6963a3d0 R08: 0000000000000000 R09: 00007f8014f1d6c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 00007fff6963a3d8 R14: 00007fff6963a658 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:6984 blocked for more than 165 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:27608 pid:6984  tgid:6984  ppid:1      task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 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
 get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
 device_add+0xc13/0x1980 drivers/base/core.c:3613
 hci_register_dev+0x328/0xce0 net/bluetooth/hci_core.c:2621
 __vhci_create_device+0x357/0x880 drivers/bluetooth/hci_vhci.c:451
 vhci_create_device drivers/bluetooth/hci_vhci.c:479 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 vhci_write+0x2c0/0x480 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe943d8e1c0
RSP: 002b:00007fff1a241958 EFLAGS: 00000202
 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fe943d8e1c0
RDX: 0000000000000002 RSI: 00007fff1a24196a RDI: 00000000000000ca
RBP: 00007fff1a241a30 R08: 0000000000000000 R09: 00007fe944b1d6c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 00007fff1a241a38 R14: 00007fff1a241cb8 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:6987 blocked for more than 166 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:28520 pid:6987  tgid:6987  ppid:1      task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 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
 get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
 device_add+0xc13/0x1980 drivers/base/core.c:3613
 hci_register_dev+0x328/0xce0 net/bluetooth/hci_core.c:2621
 __vhci_create_device+0x357/0x880 drivers/bluetooth/hci_vhci.c:451
 vhci_create_device drivers/bluetooth/hci_vhci.c:479 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 vhci_write+0x2c0/0x480 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe69918e1c0
RSP: 002b:00007ffec2c3bc38 EFLAGS: 00000202
 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fe69918e1c0
RDX: 0000000000000002 RSI: 00007ffec2c3bc4a RDI: 00000000000000ca
RBP: 00007ffec2c3bd10 R08: 0000000000000000 R09: 00007fe699f1d6c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 00007ffec2c3bd18 R14: 00007ffec2c3bf98 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:6988 blocked for more than 166 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:28520 pid:6988  tgid:6988  ppid:1      task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 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
 get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
 device_add+0xc13/0x1980 drivers/base/core.c:3613
 hci_register_dev+0x328/0xce0 net/bluetooth/hci_core.c:2621
 __vhci_create_device+0x357/0x880 drivers/bluetooth/hci_vhci.c:451
 vhci_create_device drivers/bluetooth/hci_vhci.c:479 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 vhci_write+0x2c0/0x480 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb7b958e1c0
RSP: 002b:00007fffebdfd2c8 EFLAGS: 00000202
 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fb7b958e1c0
RDX: 0000000000000002 RSI: 00007fffebdfd2da RDI: 00000000000000ca
RBP: 00007fffebdfd3a0 R08: 0000000000000000 R09: 00007fb7ba31d6c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 00007fffebdfd3a8 R14: 00007fffebdfd628 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by kworker/R-mm_pe/14:
3 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
 #0: 
ffffffff8e3c96a0
 (
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
5 locks held by kworker/u9:0/52:
 #0: 
ffff88805e7ed948
 (
(wq_completion)hci0
){+.+.}-{0:0}
, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: 
ffffc90000bd7c90
 (
(work_completion)(&hdev->cmd_sync_work)
){+.+.}-{0:0}
, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: 
ffff88805e654ec0
 (
&hdev->req_lock
){+.+.}-{4:4}
, at: hci_cmd_sync_work+0x175/0x470 net/bluetooth/hci_sync.c:331
 #3: 
ffff88805e6540c0
 (
&hdev->lock){+.+.}-{4:4}
, at: hci_abort_conn_sync+0x13f/0xb20 net/bluetooth/hci_sync.c:5702
 #4: 
ffff88801badd988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_find_and_get_ns+0x2f/0x70 fs/kernfs/dir.c:936
5 locks held by kworker/u8:15/4025:
1 lock held by udevd/5187:
 #0: 
ffff88801badd988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1183
2 locks held by getty/5575:
 #0: 
ffff88814e3cb0a0
 (
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: 
ffffc9000332b2f0
 (
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211
5 locks held by kworker/1:2/5835:
5 locks held by kworker/u9:2/5926:
 #0: 
ffff888030e2f148
 (
(wq_completion)hci3
){+.+.}-{0:0}
, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: 
ffffc9000423fc90
 (
(work_completion)(&hdev->cmd_sync_work)
){+.+.}-{0:0}
, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: 
ffff888061610ec0
 (
&hdev->req_lock
){+.+.}-{4:4}
, at: hci_cmd_sync_work+0x175/0x470 net/bluetooth/hci_sync.c:331
 #3: 
ffff8880616100c0
 (
&hdev->lock
){+.+.}-{4:4}
, at: hci_abort_conn_sync+0x13f/0xb20 net/bluetooth/hci_sync.c:5702
 #4: 
ffffffff8e3d4df8
 (
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
7 locks held by kworker/0:2/5955:
 #0: 
ffff888020af7148
 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: ffffc90005307c90 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: 
ffff888143b35198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: hub_event+0x1c0/0x52f0 drivers/usb/core/hub.c:5899
 #3: 
ffff88807ba4c198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006
 #4: 
ffff888031a7b160
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006
 #5: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
 #6: 
ffff88801badd988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_activate fs/kernfs/dir.c:1428 [inline]
, at: kernfs_add_one+0x349/0x840 fs/kernfs/dir.c:837
7 locks held by kworker/u9:4/5986:
 #0: 
ffff888075f01148
 (
(wq_completion)hci2
){+.+.}-{0:0}
, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: 
ffffc90003e4fc90
 (
(work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: ffff88805e688ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x470 net/bluetooth/hci_sync.c:331
 #3: 
ffff88805e6880c0
 (
&hdev->lock
){+.+.}-{4:4}
, at: hci_abort_conn_sync+0x13f/0xb20 net/bluetooth/hci_sync.c:5702
 #4: 
ffffffff903bee08
 (
hci_cb_list_lock
){+.+.}-{4:4}
, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2128 [inline]
, at: hci_conn_failed+0x14f/0x360 net/bluetooth/hci_conn.c:1336
 #5: 
ffff8880587f7338
 (&conn->lock
#2
){+.+.}-{4:4}
, at: l2cap_conn_del+0x80/0x760 net/bluetooth/l2cap_core.c:1763
 #6: 
ffffffff8e3d4df8
 (
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
5 locks held by kworker/u9:5/5989:
6 locks held by kworker/1:5/6123:
 #0: 
ffff888020af7148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: ffffc900030f7c90 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: ffff8880298dd198 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: hub_event+0x1c0/0x52f0 drivers/usb/core/hub.c:5899
 #3: ffff8880298f8518 (&port_dev->status_lock
){+.+.}-{4:4}
, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
, at: port_event drivers/usb/core/hub.c:5871 [inline]
, at: hub_event+0x2b87/0x52f0 drivers/usb/core/hub.c:5953
 #4: 
ffff8881437dd168 (hcd->address0_mutex
){+.+.}-{4:4}
, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
, at: port_event drivers/usb/core/hub.c:5871 [inline]
, at: hub_event+0x2bb0/0x52f0 drivers/usb/core/hub.c:5953
 #5: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}
, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:639
2 locks held by kworker/1:8/6135:
4 locks held by kworker/1:13/6324:
 #0: ffff88813ff51948 ((wq_completion)events){+.+.}-{0:0}
, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: 
ffffc90003f0fc90
 (
kernfs_notify_work
){+.+.}-{0:0}
, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: ffff88801baddab8
 (
&root->kernfs_supers_rwsem
){++++}-{4:4}
, at: kernfs_notify_workfn+0xf7/0xb30 fs/kernfs/file.c:932
 #3: ffff88801badd988 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_notify_workfn+0xff/0xb30 fs/kernfs/file.c:933
4 locks held by kworker/u9:6/6335:
 #0: ffff888061590148 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: ffffc90004977c90 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: ffff88806ac58ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x470 net/bluetooth/hci_sync.c:331
 #3: ffff88806ac580c0 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x13f/0xb20 net/bluetooth/hci_sync.c:5702
2 locks held by kworker/0:12/6522:
3 locks held by kworker/1:14/6523:
6 locks held by kworker/1:15/6534:
 #0: ffff888020af7148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: ffffc90004df7c90 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: 
ffff888143b30198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
ffff888143b30198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x52f0 drivers/usb/core/hub.c:5899
 #3: 
ffff88807b3ab198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006
 #4: 
ffff8880757f2160
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006
 #5: 
ffff88801badd988
 (
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:794
1 lock held by syz-executor/6643:
1 lock held by syz-executor/6649:
 #0: 
ffffffff8e3d4df8
 (
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by kworker/R-wg-cr/6684:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
1 lock held by kworker/R-wg-cr/6698:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
1 lock held by kworker/R-wg-cr/6699:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
1 lock held by kworker/R-wg-cr/6700:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
1 lock held by kworker/R-wg-cr/6701:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
1 lock held by kworker/R-wg-cr/6702:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
1 lock held by kworker/R-wg-cr/6707:
1 lock held by kworker/R-wg-cr/6712:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline]
, at: rescuer_thread+0x69f/0xf10 kernel/workqueue.c:3560
1 lock held by kworker/R-wg-cr/6717:
 #0: 
ffffffff8e27f128
 (
wq_pool_attach_mutex
){+.+.}-{4:4}
, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672
4 locks held by udevd/6856:
 #0: 
ffff888059f50e80
 (
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182
 #1: 
ffff88807cf44488
 (
&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: 
ffff888074405878
 (
kn->active
#28
){++++}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: 
ffff88807ba4c198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:900 [inline]
, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143
3 locks held by kworker/1:17/6915:
 #0: 
ffff88813ff51948
 (
(wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
 #1: 
ffffc90004ae7c90
 (
(work_completion)(&gadget->work)
){+.+.}-{0:0}
, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
 #2: 
ffff88801badd988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_find_and_get_ns+0x2f/0x70 fs/kernfs/dir.c:936
1 lock held by syz.2.165/6929:
 #0: 
ffff88801badd988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_remove fs/kernfs/dir.c:1552 [inline]
, at: kernfs_remove+0x2f/0x50 fs/kernfs/dir.c:1543
1 lock held by syz.0.167/6948:
 #0: 
ffff88801badd988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x3d/0x100 fs/kernfs/dir.c:1715
4 locks held by udevd/6947:
 #0: 
ffff888076a930a0
 (
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182
 #1: 
ffff88805bf9b488
 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: 
ffff888035ea04b8
 (
kn->active
#23
){++++}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: 
ffff88807b3ab198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:900 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by rm/6978:
1 lock held by syz-executor/6980:
2 locks held by syz-executor/6983:
2 locks held by syz-executor/6984:
 #0: 
ffff88805b0f9118
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (gdp_mutex){+.+.}-{4:4}, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6987:
 #0: ffff88807a2fc918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
 #0: ffff88807a2fc918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 #0: ffff88807a2fc918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: ffffffff8f2b6688
 (
gdp_mutex){+.+.}-{4:4}, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6988:
 #0: ffff88807a2fe918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
 #0: ffff88807a2fe918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 #0: ffff88807a2fe918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6990:
 #0: 
ffff888020ed3118
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6993:
 #0: 
ffff888029d64118
 (&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (gdp_mutex
){+.+.}-{4:4}, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6994:
 #0: ffff888030031918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
 #0: ffff888030031918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 #0: ffff888030031918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: ffffffff8f2b6688 (gdp_mutex){+.+.}-{4:4}, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6997:
 #0: ffff888028cf6118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
 #0: ffff888028cf6118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 #0: ffff888028cf6118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: ffffffff8f2b6688 (gdp_mutex){+.+.}-{4:4}, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/6998:
 #0: ffff88805644d918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
 #0: ffff88805644d918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 #0: ffff88805644d918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: ffffffff8f2b6688 (gdp_mutex){+.+.}-{4:4}, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/7001:
 #0: 
ffff888059c67118
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/7004:
 #0: 
ffff88805d81b118
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/7005:
 #0: 
ffff88805d81e918
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/7008:
 #0: 
ffff88805b7a8118
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/7009:
 #0: 
ffff888077a0f918
 (
&data->open_mutex
){+.+.}-{4:4}
, at: vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline]
, at: vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
, at: vhci_write+0x2b4/0x480 drivers/bluetooth/hci_vhci.c:616
 #1: 
ffffffff8f2b6688
 (
gdp_mutex
){+.+.}-{4:4}
, at: get_device_parent+0x10a/0x4e0 drivers/base/core.c:3266
2 locks held by syz-executor/7012:
 #0: 
ffff8880325ce918

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/26 02:55 upstream ccd1cdca5cd4 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in hci_register_dev
* Struck through repros no longer work on HEAD.