INFO: task syz.1.163:6738 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.163 state:D stack:27544 pid:6738 tgid:6738 ppid:5808 task_flags:0x40044c flags:0x00080003
Call Trace:
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_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
__flush_work+0x7d7/0xcc0 kernel/workqueue.c:4277
__cancel_work_sync kernel/workqueue.c:4397 [inline]
cancel_work_sync+0xd1/0xf0 kernel/workqueue.c:4434
hci_cmd_sync_clear+0x33/0x100 net/bluetooth/hci_sync.c:655
hci_unregister_dev+0x1cc/0x680 net/bluetooth/hci_core.c:2711
vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:690
__fput+0x402/0xb70 fs/file_table.c:468
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x87f/0x2bd0 kernel/exit.c:971
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8a31fc2005
RSP: 002b:00007f8a32ebff80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f8a321e5fa0 RCX: 00007f8a31fc2005
RDX: 00007f8a32ebffc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8a32013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f8a321e6038 R14: 00007f8a321e5fa0 R15: 00007ffc359d6e68
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c9620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5572:
#0: ffff88814e2f10a0 (&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
3 locks held by kworker/u9:2/5816:
#0: ffff88803339e948 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc900043dfc90 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff888021320ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x175/0x470 net/bluetooth/hci_sync.c:331
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5167 Comm: syslogd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__unix_dgram_recvmsg+0xd7/0xc30 net/unix/af_unix.c:2559
Code: 84 24 d0 00 00 00 00 00 00 00 48 c1 e8 03 48 c7 84 24 d8 00 00 00 00 00 00 00 48 c7 84 24 e0 00 00 00 00 00 00 00 80 3c 28 00 <0f> 85 46 0a 00 00 44 8b 74 24 04 31 ff 48 8b 83 a0 01 00 00 48 c7
RSP: 0018:ffffc9000416fa38 EFLAGS: 00000246
RAX: 1ffff110065385ac RBX: ffff8880329c2bc0 RCX: 0000000000000000
RDX: ffff88807ccb0000 RSI: ffffffff8a1665a5 RDI: ffff8880329c2d60
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: 00000000000000ff
R13: 0000000000000000 R14: ffffffff903148a0 R15: 00000000000000ff
FS: 00007f61ffe60c80(0000) GS:ffff888124909000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f083a3b42f8 CR3: 000000007cc02000 CR4: 00000000003526f0
Call Trace:
unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2675
sock_recvmsg_nosec net/socket.c:1078 [inline]
sock_recvmsg+0x1f9/0x250 net/socket.c:1100
sock_read_iter+0x2b9/0x3b0 net/socket.c:1170
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0xa98/0xcf0 fs/read_write.c:572
ksys_read+0x1f8/0x250 fs/read_write.c:715
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: 0033:0x7f61fffb0407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffcccf86fb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f61ffe60c80 RCX: 00007f61fffb0407
RDX: 00000000000000ff RSI: 0000559a21636300 RDI: 0000000000000000
RBP: 0000559a216362c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000559a2163633f
R13: 0000000000000000 R14: 0000559a21636300 R15: 00005599f8a0cd98