INFO: task rcu_tasks_kthre:11 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:rcu_tasks_kthre state:D stack:25360 pid: 11 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
do_wait_for_common+0x295/0x460 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
__synchronize_srcu+0x2b5/0x350 kernel/rcu/srcutree.c:930
rcu_tasks_wait_gp+0x43b/0x8e0 kernel/rcu/tasks.h:327
rcu_tasks_kthread+0x2c1/0x640 kernel/rcu/tasks.h:226
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8d11efa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3953:
#0: ffff88814c92a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:18/6479:
2 locks held by kworker/0:32/8163:
#0: ffff888017872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
#1: ffffc90003bdfd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by syz-executor/29191:
#0: ffff88805d43d3f0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1020 net/bluetooth/hci_core.c:1755
#1: ffff88805d43c478 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x408/0x1020 net/bluetooth/hci_core.c:1800
#2: ffffffff8e3b2e48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1519 [inline]
#2: ffffffff8e3b2e48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
3 locks held by syz-executor/30444:
#0: ffff888073d9d3f0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1020 net/bluetooth/hci_core.c:1755
#1: ffff888073d9c478 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x408/0x1020 net/bluetooth/hci_core.c:1800
#2: ffffffff8e3b2e48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1519 [inline]
#2: ffffffff8e3b2e48 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
2 locks held by kworker/1:41/415:
2 locks held by syz.6.7177/1967:
#0: ffffffff8d16c808 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
#1: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
2 locks held by syz.6.7455/3032:
1 lock held by syz.5.7488/3170:
#0: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#0: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
1 lock held by dhcpcd/3174:
#0: ffff888081c8e120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1744 [inline]
#0: ffff888081c8e120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xd60 net/packet/af_packet.c:3246
=============================================
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 10/07/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe1b/0xe60 kernel/hung_task.c:369
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3170 Comm: syz.5.7488 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:preempt_count_add+0x11c/0x190 kernel/sched/core.c:5504
Code: 7a ff ff ff 48 c7 c7 80 b4 2a 8a 48 c7 c6 c0 b4 2a 8a e8 17 71 6b 08 89 df 0f 0b e9 5e ff ff ff 48 c7 c1 80 cf 14 97 80 e1 07 <80> c1 03 38 c1 0f 8c 00 ff ff ff 89 fb 48 c7 c7 80 cf 14 97 e8 6b
RSP: 0018:ffffc9000305f428 EFLAGS: 00000246
RAX: 0000000000000004 RBX: 00007f3872f2e559 RCX: ffffffff9714cf00
RDX: ffffc9000305ff00 RSI: ffffffff8a7a4ba0 RDI: 0000000000000001
RBP: 000000000001f301 R08: ffffc9000305ff58 R09: 000000000000000e
R10: dffffc0000000000 R11: fffff5200060bea5 R12: ffff888019d85940
R13: 1ffff110033b0bd8 R14: 00007f3872f2e559 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c5225094b0 CR3: 000000002d486000 CR4: 00000000003506e0
DR0: 0000200000000800 DR1: 0000200000000980 DR2: 0000000000000002
DR3: 0000000000000002 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
is_module_text_address+0x17/0x140 kernel/module.c:4779
kernel_text_address kernel/extable.c:145 [inline]
__kernel_text_address+0x84/0x100 kernel/extable.c:105
unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
save_stack+0x121/0x230 mm/page_owner.c:119
__reset_page_owner+0x51/0x180 mm/page_owner.c:140
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1340 [inline]
free_pcp_prepare mm/page_alloc.c:1391 [inline]
free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
__vunmap+0x8e0/0xa80 mm/vmalloc.c:2628
kcov_put kernel/kcov.c:422 [inline]
kcov_close+0x27/0x50 kernel/kcov.c:524
__fput+0x212/0x8c0 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x635/0x2110 kernel/exit.c:890
do_group_exit+0x12c/0x2f0 kernel/exit.c:1004
get_signal+0x7eb/0x12e0 kernel/signal.c:2913
arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:157 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
__syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3872f2e559
Code: Unable to access opcode bytes at RIP 0x7f3872f2e52f.
RSP: 002b:00007f3871185028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000003 RBX: 00007f38731b4fa0 RCX: 00007f3872f2e559
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000640
RBP: 00007f3872fc5b20 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f38731b5038 R14: 00007f38731b4fa0 R15: 00007fff69559008