INFO: task kworker/u5:1:5088 blocked for more than 168 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u5:1 state:D stack:25592 pid:5088 ppid:2 flags:0x00004000
Workqueue: hci1 hci_cmd_sync_work
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
synchronize_rcu_expedited+0x6d8/0x880 kernel/rcu/tree_exp.h:1019
synchronize_rcu+0x142/0x3e0 kernel/rcu/tree.c:3627
hci_chan_del+0x114/0x1a0 net/bluetooth/hci_conn.c:2726
l2cap_conn_del+0x518/0x670 net/bluetooth/l2cap_core.c:1797
l2cap_connect_cfm+0x129/0x11a0 net/bluetooth/l2cap_core.c:7376
hci_connect_cfm include/net/bluetooth/hci_core.h:1999 [inline]
hci_conn_failed+0x1a8/0x2e0 net/bluetooth/hci_conn.c:1252
hci_abort_conn_sync+0xcbe/0xec0 net/bluetooth/hci_sync.c:5697
hci_cmd_sync_work+0x204/0x380 net/bluetooth/hci_sync.c:333
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
INFO: task kworker/u5:2:5779 blocked for more than 170 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u5:2 state:D stack:26608 pid:5779 ppid:2 flags:0x00004000
Workqueue: hci3 hci_cmd_sync_work
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747
hci_connect_cfm include/net/bluetooth/hci_core.h:1996 [inline]
hci_conn_failed+0x145/0x2e0 net/bluetooth/hci_conn.c:1252
hci_abort_conn_sync+0xcbe/0xec0 net/bluetooth/hci_sync.c:5697
hci_cmd_sync_work+0x204/0x380 net/bluetooth/hci_sync.c:333
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
INFO: task syz.2.411:7627 blocked for more than 217 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.411 state:D stack:25384 pid:7627 ppid:5783 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
Showing all locks held in the system:
2 locks held by kworker/1:1/27:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc90000a2fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90000a2fd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
1 lock held by khungtaskd/29:
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
4 locks held by kworker/u5:0/51:
#0: ffff88801f328d38 ((wq_completion)hci5#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88801f328d38 ((wq_completion)hci5#2){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc90000bbfd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90000bbfd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff888063e340b8 (&hdev->lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x97/0x900 net/bluetooth/hci_event.c:3685
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1996 [inline]
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x535/0x900 net/bluetooth/hci_event.c:3719
2 locks held by kworker/1:2/1205:
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc90004a17d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90004a17d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
2 locks held by getty/5535:
#0: ffff8880319f10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
4 locks held by kworker/u5:2/5779:
#0: ffff8880248dd538 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff8880248dd538 ((wq_completion)hci3){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc9000456fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000456fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff88807da34e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1cc/0x380 net/bluetooth/hci_sync.c:332
#3: ffff88807da340b8 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x98a/0xec0 net/bluetooth/hci_sync.c:5678
3 locks held by syz-executor/5780:
#0: ffff888066014e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff888066014e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff8880660140b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x552/0x1130 net/bluetooth/hci_sync.c:5293
#2: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x99/0x220 net/bluetooth/hci_conn.c:2564
6 locks held by kworker/u5:3/5784:
#0: ffff88805c881d38 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88805c881d38 ((wq_completion)hci2){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc900045afd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc900045afd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff88802b850e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1cc/0x380 net/bluetooth/hci_sync.c:332
#3: ffff88802b8500b8 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x98a/0xec0 net/bluetooth/hci_sync.c:5678
#4: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1996 [inline]
#4: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_failed+0x145/0x2e0 net/bluetooth/hci_conn.c:1252
#5: ffff888025c0fb38 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x6f/0x670 net/bluetooth/l2cap_core.c:1761
4 locks held by kworker/u5:4/5787:
#0: ffff888026d7e938 ((wq_completion)hci4#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888026d7e938 ((wq_completion)hci4#2){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc900045dfd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc900045dfd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff888063e380b8 (&hdev->lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x97/0x900 net/bluetooth/hci_event.c:3685
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1996 [inline]
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x535/0x900 net/bluetooth/hci_event.c:3719
2 locks held by kworker/u4:14/6128:
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6695
3 locks held by kworker/u4:15/6131:
#0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6695
#2: ffff8880b8f295d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
1 lock held by syz.2.411/7627:
#0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
3 locks held by syz.0.410/7629:
#0: ffff8880667fce70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff8880667fce70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff8880667fc0b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x552/0x1130 net/bluetooth/hci_sync.c:5293
#2: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x99/0x220 net/bluetooth/hci_conn.c:2564
4 locks held by kworker/u5:7/7658:
#0: ffff888022801138 ((wq_completion)hci6#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888022801138 ((wq_completion)hci6#2){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc9000b857d00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000b857d00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff88805a0c40b8 (&hdev->lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x97/0x900 net/bluetooth/hci_event.c:3685
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1996 [inline]
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x535/0x900 net/bluetooth/hci_event.c:3719
1 lock held by syz-executor/7664:
#0: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ed/0xf90 net/core/rtnetlink.c:6473
4 locks held by kworker/u5:8/7666:
#0: ffff88802c963538 ((wq_completion)hci7#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88802c963538 ((wq_completion)hci7#2){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc90002e97d00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90002e97d00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff88805a0c00b8 (&hdev->lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x97/0x900 net/bluetooth/hci_event.c:3685
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1996 [inline]
#3: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_remote_features_evt+0x535/0x900 net/bluetooth/hci_event.c:3719
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5814 Comm: kworker/0:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:asm_sysvec_apic_timer_interrupt+0x0/0x20 arch/x86/include/asm/idtentry.h:687
Code: e6 bd e3 ff e9 c1 04 00 00 90 f3 0f 1e fa 0f 01 ca fc 6a ff e8 c1 03 00 00 48 89 c4 48 89 e7 e8 06 bd e3 ff e9 a1 04 00 00 90 0f 1e fa 0f 01 ca fc 6a ff e8 a1 03 00 00 48 89 c4 48 89 e7 e8
RSP: 0018:ffffc9000473f978 EFLAGS: 00000093
RAX: ffffffff88bae7a1 RBX: 0000000000000000 RCX: ffff88807982bc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000473fa50 R08: ffffffff911bc597 R09: 1ffffffff22378b2
R10: dffffc0000000000 R11: fffffbfff22378b3 R12: 0000000000000200
R13: dffffc0000000000 R14: 1ffff920008e7f34 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2a299e7ae0 CR3: 0000000023bf9000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
RIP: 0010:seqcount_lockdep_reader_access+0x19a/0x1d0 include/linux/seqlock.h:105
Code: f8 4d 85 e4 75 16 e8 c5 fd cb f8 eb 15 e8 be fd cb f8 e8 a9 f0 c8 01 4d 85 e4 74 ea e8 af fd cb f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc9000473f9a0 EFLAGS: 00000293
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:350 [inline]
gc_worker+0x314/0x14a0 net/netfilter/nf_conntrack_core.c:1504
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293