INFO: task syz.4.964:10366 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.964 state:D stack:26864 pid:10366 tgid:10365 ppid:5855 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760
nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fae73f8f6c9
RSP: 002b:00007fae74f01038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fae741e5fa0 RCX: 00007fae73f8f6c9
RDX: 0000000020048000 RSI: 0000200000000000 RDI: 0000000000000003
RBP: 00007fae74011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fae741e6038 R14: 00007fae741e5fa0 R15: 00007fffcb03c658
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c4720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c4720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c4720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5570:
#0: ffff88814dae50a0 (&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/0x14f0 drivers/tty/n_tty.c:2222
5 locks held by kworker/u8:11/8947:
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:646 [inline]
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:631
#1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:220 [inline]
#1: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: __schedule+0x1861/0x5de0 kernel/sched/core.c:6923
#2: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: psi_enqueue kernel/sched/stats.h:166 [inline]
#2: ffff8880b8424088 (psi_seq){-.-.}-{0:0}, at: enqueue_task+0x20e/0x4e0 kernel/sched/core.c:2094
#3: ffffffff9acf9db0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x14c/0x4c0 lib/debugobjects.c:818
#4: ffffffff8e281ac8 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
2 locks held by syz.3.961/10333:
#0: ffffffff9018b190 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ee168 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
2 locks held by syz.4.964/10366:
#0: ffffffff9018b190 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ee168 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1880
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
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]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf3f/0x1170 kernel/hung_task.c:495
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5840 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:mark_lock+0x99/0x610 kernel/locking/lockdep.c:4774
Code: a0 49 a8 95 4c 89 ea 48 23 50 60 b8 01 00 00 00 74 7f 48 8b 54 24 68 65 48 2b 15 fa e3 08 12 0f 85 e8 04 00 00 48 8d 65 d8 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc f6 46 22 03 74 8d 41 bd
RSP: 0018:ffffc900040afab8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000008
RDX: 0000000000000000 RSI: ffff888034d2d430 RDI: ffff888034d2c900
RBP: ffffc900040afad8 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888034d2d430
R13: 0000000000000100 R14: 0000000000000000 R15: ffff888034d2c900
FS: 000055556ef60500(0000) GS:ffff888124b08000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f700b9b4198 CR3: 0000000073d6e000 CR4: 00000000003526f0
Call Trace:
mark_usage kernel/locking/lockdep.c:4674 [inline]
__lock_acquire+0x3e9/0x1c90 kernel/locking/lockdep.c:5191
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
__debug_object_init+0xec/0x3d0 lib/debugobjects.c:741
debug_hrtimer_init_on_stack kernel/time/hrtimer.c:432 [inline]
debug_setup_on_stack kernel/time/hrtimer.c:470 [inline]
hrtimer_setup_sleeper_on_stack kernel/time/hrtimer.c:2083 [inline]
hrtimer_nanosleep+0xa0/0x380 kernel/time/hrtimer.c:2161
common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1352
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1398 [inline]
__se_sys_clock_nanosleep kernel/time/posix-timers.c:1375 [inline]
__x64_sys_clock_nanosleep+0x34d/0x4a0 kernel/time/posix-timers.c:1375
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff3e01c1f43
Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 1e 66 1f 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10
RSP: 002b:00007ffc105f0478 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff3e01c1f43
RDX: 00007ffc105f0490 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000023ae0 R09: 00007ff3e0fff000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc105f08e0
R13: 0000000000000004 R14: 00007ffc105f04cc R15: 00007ffc105f0560