INFO: task syz.6.12367:1038 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.12367 state:D stack:26120 pid:1038 tgid:1037 ppid:32549 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5263 [inline]
__schedule+0x1836/0x4ed0 kernel/sched/core.c:6871
__schedule_loop kernel/sched/core.c:6953 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6968
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7025
__mutex_lock_common kernel/locking/mutex.c:686 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:770
nfsd_nl_rpc_status_get_dumpit+0xdf/0x1290 fs/nfsd/nfsctl.c:1477
genl_dumpit+0x10b/0x1b0 net/netlink/genetlink.c:1027
netlink_dump+0x6e4/0xe90 net/netlink/af_netlink.c:2325
__netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2440
genl_family_rcv_msg_dumpit+0x1e7/0x2c0 net/netlink/genetlink.c:1076
genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline]
genl_rcv_msg+0x5da/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:746
____sys_sendmsg+0x505/0x870 net/socket.c:2634
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2688
__sys_sendmsg net/socket.c:2720 [inline]
__do_sys_sendmsg net/socket.c:2725 [inline]
__se_sys_sendmsg net/socket.c:2723 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2723
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6850f8f6c9
RSP: 002b:00007f6851d53038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f68511e5fa0 RCX: 00007f6850f8f6c9
RDX: 0000000000000800 RSI: 0000200000000180 RDI: 0000000000000003
RBP: 00007f6851011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f68511e6038 R14: 00007f68511e5fa0 R15: 00007ffe6eda81a8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by udevd/5202:
2 locks held by getty/5592:
#0: ffff88814d8070a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.2.8258/24435:
#0: ffffffff8f340a30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e22ae68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1880
5 locks held by kworker/u8:2/31263:
#0: ffff8880b873a3d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
#1: ffff8880b8724248 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#2: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
#2: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479
#3: ffffffff99a846f8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
#4: ffffffff8df3d740 (rcu_read_lock){....}-{1:3}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
3 locks held by syz.6.12367/1038:
#0: ffffffff8f340a30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff88802bd586f0 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404
#2: ffffffff8e22ae68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdf/0x1290 fs/nfsd/nfsctl.c:1477
1 lock held by kworker/u8:8/3318:
3 locks held by kworker/u8:11/6946:
#0: ffff8880b873a3d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
#1: ffff8880b8724248 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff8880b8725d98 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
#2: ffff8880b8725d98 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085
=============================================
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+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 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+0xfb5/0x1000 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 83 f1 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 63 0f 0d 00 f3 0f 1e fa fb f4 58 f1 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: d3da4cc697e0f200 RBX: ffffffff81979497 RCX: d3da4cc697e0f200
RDX: 0000000000000001 RSI: ffffffff8d78e538 RDI: ffffffff8bbf8160
RBP: ffffc90000197f10 R08: ffff8880b873339b R09: 1ffff110170e6673
R10: dffffc0000000000 R11: ffffed10170e6674 R12: ffffffff8f7de470
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039dcb70
FS: 0000000000000000(0000) GS:ffff888125fbc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557cb705c8 CR3: 000000007796c000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147