INFO: task udevd:4294 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:27344 pid:4294  ppid:3638   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
 device_lock include/linux/device.h:885 [inline]
 uevent_show+0x16e/0x320 drivers/base/core.c:2669
 dev_attr_show+0x50/0xb0 drivers/base/core.c:2372
 sysfs_kf_seq_show+0x349/0x4b0 fs/sysfs/file.c:59
 seq_read_iter+0x460/0xc50 fs/seq_file.c:230
 call_read_iter include/linux/fs.h:2265 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x471/0x960 fs/read_write.c:470
 ksys_read+0x14d/0x260 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f72ed4a7407
RSP: 002b:00007fff3da37810 EFLAGS: 00000202
 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f72edc9b880 RCX: 00007f72ed4a7407
RDX: 0000000000001000 RSI: 00005602569dea00 RDI: 0000000000000008
RBP: 00007f72ed5efff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007f72ed5efea0 R14: 0000000000000000 R15: 00005602569dc7a0
 </TASK>
INFO: task khidpd_4c4a4155:4436 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:khidpd_4c4a4155 state:D
 stack:28592 pid:4436  ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x2c2/0x590 kernel/sched/completion.c:138
 __flush_work+0x938/0xac0 kernel/workqueue.c:3076
 __cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3163
 hidp_session_remove+0xaa/0x2a0 net/bluetooth/hidp/core.c:1199
 l2cap_unregister_user+0x180/0x1a0 net/bluetooth/l2cap_core.c:1786
 hidp_session_thread+0x18d2/0x1960 net/bluetooth/hidp/core.c:1335
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task syz.0.47:4496 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.47        state:D
 stack:27664 pid:4496  ppid:4377   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
 l2cap_chan_connect+0xfb/0xe20 net/bluetooth/l2cap_core.c:7308
 l2cap_sock_connect+0x576/0x750 net/bluetooth/l2cap_sock.c:257
 __sys_connect_file net/socket.c:2011 [inline]
 __sys_connect+0x3cb/0x450 net/socket.c:2028
 __do_sys_connect net/socket.c:2038 [inline]
 __se_sys_connect net/socket.c:2035 [inline]
 __x64_sys_connect+0x76/0x80 net/socket.c:2035
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f34a459e159
RSP: 002b:00007f34a544b028 EFLAGS: 00000246
 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f34a4825fa0 RCX: 00007f34a459e159
RDX: 000000000000000e RSI: 0000200000000080 RDI: 0000000000000004
RBP: 00007f34a463506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f34a4826038 R14: 00007f34a4825fa0 R15: 00007ffc9a611478
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2e230 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: 
ffffffff8cb2ea50
 (
rcu_tasks_trace.tasks_gp_mutex
){+.+.}-{3:3}
, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
 #0: ffffffff8cb2d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2d8a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6669
4 locks held by kworker/1:2/127:
2 locks held by getty/4033:
 #0: 
ffff88814d2b3098
 (&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
4 locks held by udevd/4294:
 #0: ffff888029aedd58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0x9d/0xc50 fs/seq_file.c:182
 #1: ffff88807c0ac088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x59/0x410 fs/kernfs/file.c:172
 #2: 
ffff88807576cda0
 (
kn->active
#5
){.+.+}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xae/0x410 fs/kernfs/file.c:173
 #3: ffff88807e575a20 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #3: ffff88807e575a20 (&dev->mutex){....}-{3:3}, at: uevent_show+0x16e/0x320 drivers/base/core.c:2669
3 locks held by kworker/0:21/4432:
 #0: ffff888017471938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: ffffc90003467d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd56d68 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x82/0xd40 net/wireless/reg.c:2499
3 locks held by kworker/0:22/4433:
 #0: ffff88802f09a938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: 
ffffc90003477d00
 (
(work_completion)(&(&ifa->dad_work)->work)
){+.+.}-{0:0}
, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #2: 
ffffffff8dd56d68
 (
rtnl_mutex
){+.+.}-{3:3}
, at: addrconf_dad_work+0xc4/0x1500 net/ipv6/addrconf.c:4146
2 locks held by khidpd_4c4a4155/4436:
 #0: 
ffff888018e88428 (&hdev->lock){+.+.}-{3:3}
, at: l2cap_unregister_user+0x67/0x1a0 net/bluetooth/l2cap_core.c:1780
 #1: 
ffffffff8dee0db0
 (
hidp_session_sem
){++++}-{3:3}
, at: hidp_session_remove+0x28/0x2a0 net/bluetooth/hidp/core.c:1186
1 lock held by syz.0.47/4496:
 #0: 
ffff888018e88428
 (
&hdev->lock
){+.+.}-{3:3}
, at: l2cap_chan_connect+0xfb/0xe20 net/bluetooth/l2cap_core.c:7308
3 locks held by syz-executor/4499:
 #0: 
ffffffff8dd56d68
 (
rtnl_mutex
){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6163
 #1: 
ffff88801e3453e8
 (
&wg->device_update_lock
){+.+.}-{3:3}
, at: wg_open+0x223/0x420 drivers/net/wireguard/device.c:49
 #2: 
ffffffff8cb33578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
ffffffff8cb33578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
2 locks held by dhcpcd/4510:
 #0: ffff888072604130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff888072604130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
 #1: ffffffff8cb33578 (rcu_state.exp_mutex){+.+.}-{3:3}
, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
1 lock held by dhcpcd/4511:
 #0: 
ffff888077250130
 (
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1805 [inline]
, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
1 lock held by dhcpcd/4512:
 #0: 
ffff88807b630130
 (
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1805 [inline]
, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
1 lock held by dhcpcd/4513:
 #0: 
ffff8880733f0130
 (
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1805 [inline]
, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
1 lock held by dhcpcd/4514:
 #0: 
ffff88805dae8130
 (
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1805 [inline]
, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
1 lock held by dhcpcd/4515:
 #0: 
ffff8880203f2130
 (
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1805 [inline]
, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
1 lock held by syz-executor/4517:
 #0: 
ffffffff8dd56d68
 (rtnl_mutex){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6163
1 lock held by syz-executor/4520:
 #0: 
ffffffff8dd56d68
 (
rtnl_mutex
){+.+.}-{3:3}
, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6163

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 127 Comm: kworker/1:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: events hidp_session_dev_work
RIP: 0010:io_serial_in+0x73/0xb0 drivers/tty/serial/8250/8250_port.c:461
Code: e8 62 1f fa fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 e3 79 4b fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 44 89 f9 80 e1 07 38 c1 7c aa 4c
RSP: 0018:ffffc90002de6dd8 EFLAGS: 00000006
RAX: 1ffffffff2df8205 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc90002de6fb0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520005bcd9c R12: dffffc0000000000
R13: ffffffff96c7ce00 R14: ffffffff96fc1580 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffb54065030 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 serial_port_in include/linux/serial_core.h:668 [inline]
 serial8250_console_write+0x280/0x18b0 drivers/tty/serial/8250/8250_port.c:3450
 call_console_driver kernel/printk/printk.c:1977 [inline]
 console_emit_next_record+0x795/0xb50 kernel/printk/printk.c:2777
 console_flush_all kernel/printk/printk.c:-1 [inline]
 console_unlock+0x223/0x630 kernel/printk/printk.c:2906
 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303
 dev_vprintk_emit+0x32c/0x3de drivers/base/core.c:4948
 dev_printk_emit+0xeb/0x139 drivers/base/core.c:4959
 _dev_warn+0x11b/0x16c drivers/base/core.c:5015
 hid_parser_main+0x7d3/0xb80 drivers/hid/hid-core.c:643
 hid_open_report+0x84c/0xed0 drivers/hid/hid-core.c:1287
 hid_parse include/linux/hid.h:1135 [inline]
 hid_generic_probe+0x39/0x80 drivers/hid/hid-generic.c:63
 __hid_device_probe drivers/hid/hid-core.c:2678 [inline]
 hid_device_probe+0x2b8/0x520 drivers/hid/hid-core.c:2717
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x24a/0xb40 drivers/base/dd.c:638
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:804
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:834
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:962
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a7/0x480 drivers/base/dd.c:1034
 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
 device_add+0xbcf/0x1050 drivers/base/core.c:3712
 hid_add_device+0x361/0x500 drivers/hid/hid-core.c:2863
 hidp_session_dev_add net/bluetooth/hidp/core.c:876 [inline]
 hidp_session_dev_work+0x41/0x150 net/bluetooth/hidp/core.c:915
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>