INFO: task syz.7.8137:5576 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.8137 state:D stack:26848 pid:5576 tgid:5575 ppid:28126 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
nfsd_nl_listener_get_doit+0x10a/0x5e0 fs/nfsd/nfsctl.c:2036
genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
____sys_sendmsg+0x505/0x820 net/socket.c:2592
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe8d238f749
RSP: 002b:00007fe8d3291038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fe8d25e5fa0 RCX: 00007fe8d238f749
RDX: 0000000004000000 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007fe8d2413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe8d25e6038 R14: 00007fe8d25e5fa0 R15: 00007ffe020c9688
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5590:
#0: ffff88814c9d90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/5816:
2 locks held by syz.4.7347/2270:
#0: ffffffff8f379eb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2379a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1886
2 locks held by syz.7.8137/5576:
#0: ffffffff8f379eb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2379a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_get_doit+0x10a/0x5e0 fs/nfsd/nfsctl.c:2036
=============================================
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_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5816 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:__bfs kernel/locking/lockdep.c:1753 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1822/0x2cf0 kernel/locking/lockdep.c:5237
Code: 00 0f 83 8a 01 00 00 4e 8b 24 fd 80 78 88 95 ff c0 25 ff 0f 00 00 89 05 dc ed ea 13 4d 85 e4 0f 84 b2 01 00 00 49 8b 44 24 10 <48> 85 c0 0f 84 1c 0d 00 00 8b 0d c7 ed ea 13 39 48 5c 0f 84 67 ff
RSP: 0018:ffffc9000400f690 EFLAGS: 00000082
RAX: ffffffff932a69e8 RBX: 00000000000003dd RCX: ffffffff96255f58
RDX: ffffffff9624e1c8 RSI: ffff888078c248f8 RDI: 00000000000003dd
RBP: 28d2364f1b18a3d4 R08: ffffc9000400f658 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff819e5cf0 R12: ffffffff96255f58
R13: ffff888078c248f8 R14: ffff888078c23d00 R15: 0000000000000355
FS: 0000000000000000(0000) GS:ffff888125f1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa945517d60 CR3: 000000000dd3a000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162
lock_timer_base kernel/time/timer.c:1004 [inline]
__mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085
queue_delayed_work_on+0x11a/0x1d0 kernel/workqueue.c:2555
psi_task_change+0x118/0x340 kernel/sched/psi.c:922
psi_enqueue kernel/sched/stats.h:166 [inline]
enqueue_task+0x3e3/0x4c0 kernel/sched/core.c:2096
activate_task kernel/sched/core.c:2135 [inline]
ttwu_do_activate+0x1dc/0x860 kernel/sched/core.c:3631
ttwu_queue kernel/sched/core.c:3894 [inline]
try_to_wake_up+0x721/0x12b0 kernel/sched/core.c:4218
autoremove_wake_function+0x17/0x100 kernel/sched/wait.c:403
__wake_up_common kernel/sched/wait.c:108 [inline]
__wake_up_common_lock+0x137/0x1f0 kernel/sched/wait.c:125
pipe_release+0x171/0x330 fs/pipe.c:737
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x694/0x22f0 kernel/exit.c:971
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
__do_sys_exit_group kernel/exit.c:1123 [inline]
__se_sys_exit_group kernel/exit.c:1121 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121
x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa94478f749
Code: Unable to access opcode bytes at 0x7fa94478f71f.
RSP: 002b:00007ffd968a5ad8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fa944830661 RCX: 00007fa94478f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007fa94483067f R08: 00007ffd968a3875 R09: 0000000000000004
R10: 000000000000000b R11: 0000000000000246 R12: 0000000000000068
R13: 0000000000000004 R14: 00007ffd968a5bfc R15: 00007ffd968a5c90