INFO: task syz.4.14918:13228 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.14918 state:D stack:24120 pid:13228 tgid:13226 ppid:2153 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x14ea/0x5050 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
nfsd_nl_version_get_doit+0x17c/0xc40 fs/nfsd/nfsctl.c:1811
genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x232/0x4b0 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+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa68/0xad0 net/socket.c:2592
___sys_sendmsg+0x2a5/0x360 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+0x1bd/0x2a0 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fda3eb9aeb9
RSP: 002b:00007fda3fa54028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fda3ee15fa0 RCX: 00007fda3eb9aeb9
RDX: 0000000020044042 RSI: 0000200000000780 RDI: 000000000000000c
RBP: 00007fda3ec08c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fda3ee16038 R14: 00007fda3ee15fa0 R15: 00007ffedb92b678
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5583:
#0: ffff8880347300a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:8/3747:
1 lock held by udevd/6127:
#0: ffff888024fd3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962
2 locks held by syz.0.13863/8589:
#0: ffffffff8fa1a230 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e8793e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x16c0 fs/nfsd/nfsctl.c:1886
2 locks held by syz.4.14918/13228:
#0: ffffffff8fa1a230 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e8793e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x17c/0xc40 fs/nfsd/nfsctl.c:1811
1 lock held by dhcpcd-run-hook/19668:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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:161 [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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 19669 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:__lock_acquire+0x6c8/0x2cf0 kernel/locking/lockdep.c:5207
Code: 00 00 4c 8b 74 24 08 4c 89 f7 4c 89 ee ba 08 00 00 00 e8 3b 44 00 00 31 ed 85 c0 0f 84 6d 0d 00 00 83 3d ba bc 5d 18 00 75 13 <48> 63 44 24 18 48 0f a3 05 cb 2c 5a 12 0f 83 8a 1e 00 00 49 8b 9e
RSP: 0000:ffffc9000e067878 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff888027b29e80 RCX: ffffffff939c06f0
RDX: 0000000000000008 RSI: ffff888027b2a9d8 RDI: ffff888027b29e80
RBP: 0000000000000000 R08: ffffffff8212d6ff R09: ffffffff8e690fe0
R10: dffffc0000000000 R11: fffff940002b8ec1 R12: 00000000000000a8
R13: ffff888027b2a9d8 R14: ffff888027b29e80 R15: ffff888027b2a9b0
FS: 00007f8a9f97dc80(0000) GS:ffff8881256f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ebaaf6ebd8 CR3: 00000000806c4000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
mmu_notifier_invalidate_range_start include/linux/mmu_notifier.h:436 [inline]
wp_page_copy mm/memory.c:3753 [inline]
do_wp_page+0x3b00/0x5990 mm/memory.c:4183
handle_pte_fault mm/memory.c:6292 [inline]
__handle_mm_fault mm/memory.c:6414 [inline]
handle_mm_fault+0x1520/0x32a0 mm/memory.c:6583
do_user_addr_fault+0xa73/0x1360 arch/x86/mm/fault.c:1334
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f8a9fadffd6
Code: 1d 87 e2 13 00 48 39 5f 08 0f 84 fe 00 00 00 42 0f b7 34 72 48 3b 35 31 72 13 00 48 89 f0 0f 83 80 00 00 00 48 89 f9 83 c0 01 <48> 89 5f 08 48 c1 e9 0c 4a 33 8c f2 80 00 00 00 48 89 0f 4a 89 bc
RSP: 002b:00007ffe9a71f590 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 234aa1d3bb01653e RCX: 000055ebaaf6ebd0
RDX: 000055ebaaf67010 RSI: 0000000000000000 RDI: 000055ebaaf6ebd0
RBP: 000055ebaaf6ebc0 R08: 0000000000000410 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: ffffffffffffff88
R13: 0000000000000002 R14: 000000000000003f R15: 00007f8a9fc17ac0