INFO: task syz.4.3340:13128 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3340 state:D stack:27256 pid:13128 tgid:13127 ppid:5843 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
nfsd_nl_rpc_status_get_dumpit+0xb6/0x1170 fs/nfsd/nfsctl.c:1516
genl_dumpit+0x122/0x230 net/netlink/genetlink.c:1027
netlink_dump+0x539/0xd30 net/netlink/af_netlink.c:2327
__netlink_dump_start+0x6d6/0x990 net/netlink/af_netlink.c:2442
genl_family_rcv_msg_dumpit+0x1e2/0x2e0 net/netlink/genetlink.c:1076
genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline]
genl_rcv_msg+0x46e/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+0x5a7/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg net/socket.c:729 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2614
___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
__sys_sendmsg+0x16d/0x220 net/socket.c:2700
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8135d8eba9
RSP: 002b:00007f8136c23038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8135fd5fa0 RCX: 00007f8135d8eba9
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000003
RBP: 00007f8135e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8135fd6038 R14: 00007f8135fd5fa0 R15: 00007ffedd9b9148
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c15a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c15a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c15a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5604:
#0: ffff88814cf1d0a0 (&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
3 locks held by kworker/1:6/6018:
2 locks held by syz.0.2152/10433:
#0: ffffffff90428590 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9dabe8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629
3 locks held by syz.4.3340/13128:
#0: ffffffff90428590 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff888034bc96d8 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0x150/0x990 net/netlink/af_netlink.c:2406
#2: ffffffff8e9dabe8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xb6/0x1170 fs/nfsd/nfsctl.c:1516
2 locks held by syz.6.3783/14116:
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: deactivate_super fs/super.c:506 [inline]
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503
#1: ffffffff8e9dabe8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596
2 locks held by syz.7.3803/14165:
#0: ffffffff90428590 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9dabe8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919
1 lock held by syz.3.3922/14439:
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121
2 locks held by syz.2.3955/14510:
#0: ffffffff903850c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff903850c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433
#1: ffffffff8e5ccb38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
3 locks held by syz.8.4256/15226:
#0: ffff88805d7e8dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:499
#1: ffff88805d7e80b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x3ae/0x11d0 net/bluetooth/hci_sync.c:5282
#2: ffffffff905ed7e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2094 [inline]
#2: ffffffff905ed7e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x260 net/bluetooth/hci_conn.c:2599
1 lock held by syz.9.4361/15443:
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807f98c0e0 (&type->s_umount_key#81){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121
3 locks held by syz.0.4431/15590:
#0: ffff88805d568dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:499
#1: ffff88805d5680b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x3ae/0x11d0 net/bluetooth/hci_sync.c:5282
#2: ffffffff905ed7e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2094 [inline]
#2: ffffffff905ed7e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x260 net/bluetooth/hci_conn.c:2599
1 lock held by dhcpcd-run-hook/18407:
=============================================
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 08/18/2025
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:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 18413 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:copy_process+0x1b8f/0x7690 kernel/fork.c:2079
Code: 03 80 3c 02 00 0f 85 53 5a 00 00 49 8d bf 58 07 00 00 48 b8 00 00 00 00 00 fc ff df 49 c7 87 50 07 00 00 00 00 00 00 48 89 fa <48> c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 16 5a 00 00 49 8d
RSP: 0018:ffffc900035cfb40 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff888022342b60 RCX: 0000000000000000
RDX: ffff888022342b98 RSI: 0000000000000001 RDI: ffff888022342b98
RBP: ffffc900035cfca8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888022342e10
R13: ffff888022342a48 R14: 0000000001200000 R15: ffff888022342440
FS: 00007f34dfebec80(0000) GS:ffff8881246b5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f34e01227e8 CR3: 000000004c8e1000 CR4: 00000000003526f0
Call Trace:
kernel_clone+0xfc/0x930 kernel/fork.c:2605
__do_sys_clone+0xce/0x120 kernel/fork.c:2748
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f34e0058636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffe6423b8c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffe6423b8c8 RCX: 00007f34e0058636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055a5efa9f810 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f34dfebef50 R11: 0000000000000246 R12: 000055a5efaa1d40
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000