INFO: task syz.2.1064:9842 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc3-syzkaller-00922-g8f240030794c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1064      state:D stack:26184 pid:9842  tgid:9841  ppid:5842   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 nfsd_nl_rpc_status_get_dumpit+0xd9/0x1280 fs/nfsd/nfsctl.c:1516
 genl_dumpit+0x10b/0x1b0 net/netlink/genetlink.c:1027
 netlink_dump+0x62d/0xe20 net/netlink/af_netlink.c:2309
 __netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2424
 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:2534
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa48dd8e929
RSP: 002b:00007fa48eba1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa48dfb5fa0 RCX: 00007fa48dd8e929
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000006
RBP: 00007fa48de10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa48dfb5fa0 R15: 00007ffe0eca2e48
 </TASK>
INFO: task syz.5.1084:9934 blocked for more than 144 seconds.
      Not tainted 6.16.0-rc3-syzkaller-00922-g8f240030794c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1084      state:D stack:22408 pid:9934  tgid:9932  ppid:8384   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1922
 genl_family_rcv_msg_doit+0x212/0x300 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:2534
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3110b8e929
RSP: 002b:00007f3111a5e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3110db5fa0 RCX: 00007f3110b8e929
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000005
RBP: 00007f3110c10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3110db5fa0 R15: 00007fff89ab87d8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/1:3/1226:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc9000404fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000404fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff888041065240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
2 locks held by getty/5591:
 #0: ffff8880350a10a0 (&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
3 locks held by kworker/1:4/5902:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc9000b3afbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000b3afbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff888079d86240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
2 locks held by syz.1.440/7635:
 #0: ffffffff8f5775f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e41cd48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1922
3 locks held by syz.2.1064/9842:
 #0: ffffffff8f5775f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffff888022b316d0 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2388
 #2: ffffffff8e41cd48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xd9/0x1280 fs/nfsd/nfsctl.c:1516
2 locks held by syz.5.1084/9934:
 #0: ffffffff8f5775f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e41cd48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1922
5 locks held by syz-executor/10236:
 #0: ffff888078b10dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline]
 #0: ffff888078b10dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2717
 #1: ffff888078b100b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5238
 #2: ffffffff8f679628 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2068 [inline]
 #2: ffffffff8f679628 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2560
 #3: ffff88807bb66b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762
 #4: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
 #4: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz.7.1470/11395:
 #0: ffffffff8f5775f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8e41cd48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1922
1 lock held by syz-executor/13359:
 #0: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
1 lock held by syz-executor/13361:
 #0: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
3 locks held by kworker/u8:31/13636:
 #0: ffff88814bd9f148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88814bd9f148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc90002e67bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90002e67bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198
3 locks held by syz.0.2045/13726:
 #0: ffffffff8f512888 (rtnl_mutex){+.+.}-{4:4}, at: bpf_xdp_link_release+0x29/0x550 net/core/dev.c:10268
 #1: ffffffff8f515b08 (bpf_dispatcher_xdp.mutex){+.+.}-{4:4}, at: bpf_dispatcher_change_prog+0x9c/0xc90 kernel/bpf/dispatcher.c:146
 #2: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #2: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc3-syzkaller-00922-g8f240030794c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:470
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13359 Comm: syz-executor Not tainted 6.16.0-rc3-syzkaller-00922-g8f240030794c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:416
Code: fa 78 fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 2c 7c dc fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 f9 80 e1 07 38 c1
RSP: 0018:ffffc9000bd56430 EFLAGS: 00000002
RAX: 0000000000000033 RBX: 0000000000000033 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00000000000003f8 R08: ffff8880247e0237 R09: 1ffff110048fc046
R10: dffffc0000000000 R11: ffffffff85475330 R12: dffffc0000000000
R13: ffffffff99acc8ca R14: ffffffff99dd1920 R15: 0000000000000000
FS:  000055556c7d5500(0000) GS:ffff888125c48000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89878e8710 CR3: 000000007315a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 serial_port_out include/linux/serial_core.h:798 [inline]
 serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3306 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
 serial8250_console_write+0x140d/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456
 console_emit_next_record kernel/printk/printk.c:3138 [inline]
 console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
 _printk+0xcf/0x120 kernel/printk/printk.c:2475
 netdev_info+0x10a/0x160 net/core/dev.c:12605
 __dev_set_promiscuity+0x307/0x740 net/core/dev.c:9309
 __dev_set_rx_mode+0x17c/0x260 net/core/dev.c:-1
 dev_uc_add+0xc8/0x120 net/core/dev_addr_lists.c:693
 macvlan_open+0x446/0x8e0 drivers/net/macvlan.c:647
 __dev_open+0x470/0x880 net/core/dev.c:1683
 __dev_change_flags+0x1ea/0x6d0 net/core/dev.c:9497
 netif_change_flags+0x88/0x1a0 net/core/dev.c:9560
 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3141
 rtnl_changelink net/core/rtnetlink.c:3759 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
 rtnl_newlink+0x160b/0x1c70 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6944
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 __sys_sendto+0x3bd/0x520 net/socket.c:2228
 __do_sys_sendto net/socket.c:2235 [inline]
 __se_sys_sendto net/socket.c:2231 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2231
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f88b6d907bc
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007fffaca7b640 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f88b7ae4620 RCX: 00007f88b6d907bc
RDX: 000000000000002c RSI: 00007f88b7ae4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fffaca7b694 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f88b7ae4670 R15: 0000000000000000
 </TASK>