INFO: task syz.5.2026:14064 blocked for more than 143 seconds.
Not tainted 6.13.0-rc2-syzkaller-00031-gf92f4749861b #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2026 state:D stack:25552 pid:14064 tgid:14063 ppid:6750 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5369 [inline]
__schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
__schedule_loop kernel/sched/core.c:6833 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6848
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
__mutex_lock_common kernel/locking/mutex.c:665 [inline]
__mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735
nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964
genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347
netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891
sock_sendmsg_nosec net/socket.c:711 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:726
____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
___sys_sendmsg net/socket.c:2637 [inline]
__sys_sendmsg+0x269/0x350 net/socket.c:2669
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcff4d7ff19
RSP: 002b:00007fcff5b99058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fcff4f45fa0 RCX: 00007fcff4d7ff19
RDX: 0000000024000100 RSI: 0000000020001740 RDI: 0000000000000003
RBP: 00007fcff4df3cc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcff4f45fa0 R15: 00007ffea05df6f8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744
1 lock held by dhcpcd/5485:
2 locks held by getty/5571:
#0: ffff88814d3770a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000330b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
5 locks held by kworker/0:4/5898:
3 locks held by kworker/u9:0/10236:
#0: ffff8880435a6948 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff8880435a6948 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310
#1: ffffc9000c03fd00 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc9000c03fd00 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310
#2: ffff888034cecd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_open net/bluetooth/hci_core.c:410 [inline]
#2: ffff888034cecd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_power_on+0x1bf/0x6b0 net/bluetooth/hci_core.c:941
2 locks held by syz.8.2022/14053:
#0: ffffffff8fd01950 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ebff248 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964
2 locks held by syz.5.2026/14064:
#0: ffffffff8fd01950 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ebff248 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964
2 locks held by syz.9.2501/16632:
#0: ffff8880246fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline]
#0: ffff8880246fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:335 [inline]
#0: ffff8880246fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline]
#0: ffff8880246fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0x5c/0x200 drivers/tty/tty_ldisc.c:780
#1: ffff8880246ff0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:295 [inline]
#1: ffff8880246ff0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:337 [inline]
#1: ffff8880246ff0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline]
#1: ffff8880246ff0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0x80/0x200 drivers/tty/tty_ldisc.c:780
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc2-syzkaller-00031-gf92f4749861b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
watchdog+0xff6/0x1040 kernel/hung_task.c:397
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5944 Comm: kworker/u8:8 Not tainted 6.13.0-rc2-syzkaller-00031-gf92f4749861b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound kfree_rcu_work
RIP: 0010:debug_object_active_state+0x16e/0x360 lib/debugobjects.c:1048
Code: 8d b4 c9 80 d8 53 9a 48 8d bc c9 88 d8 53 9a 48 89 7c 24 18 e8 83 51 02 07 48 89 44 24 10 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 f7 e8 78 8e 42 fd 48 89 1c 24 4d 8b 3e 45 31 f6 eb 06
RSP: 0018:ffffc90004597940 EFLAGS: 00000046
RAX: 1ffffffff34c167f RBX: 1ffff920008b2f2c RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90004597820
RBP: ffffc90004597a40 R08: 0000000000000003 R09: fffff520008b2f04
R10: dffffc0000000000 R11: fffff520008b2f04 R12: dffffc0000000000
R13: ffff8880570cec80 R14: ffffffff9a60b3f8 R15: ffffc90004597990
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdc096d2f8 CR3: 000000000e736000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
debug_rcu_head_unqueue kernel/rcu/rcu.h:233 [inline]
debug_rcu_bhead_unqueue kernel/rcu/tree.c:3301 [inline]
kvfree_rcu_bulk+0xc5/0x4e0 kernel/rcu/tree.c:3378
kfree_rcu_work+0x44b/0x500 kernel/rcu/tree.c:3464
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244