INFO: task syz.8.2038:14633 blocked for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.2038      state:D stack:27088 pid:14633 tgid:14631 ppid:13680  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x16dc/0x5500 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607
 rt_mutex_slowlock_block+0x55c/0x680 kernel/locking/rtmutex.c:1670
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
 __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
 rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
 __rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
 __mutex_lock_common kernel/locking/rtmutex_api.c:560 [inline]
 mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:578
 nfsd_nl_listener_get_doit+0x11a/0x6a0 fs/nfsd/nfsctl.c:2114
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x565/0x870 net/socket.c:2684
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0x1b7/0x290 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f164102de99
RSP: 002b:00007f163f286028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f16412b5fa0 RCX: 00007f164102de99
RDX: 0000000004000080 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007f16410c3eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f16412b6038 R14: 00007f16412b5fa0 R15: 00007ffc6f91dfb8
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/37:
 #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/1:1/43:
 #0: ffff888021e8a138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff888021e8a138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc90000b47c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc90000b47c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffff888029f0a210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
 #2: ffff888029f0a210 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4cf0 drivers/usb/core/hub.c:5899
 #3: ffff88805ff2a210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
 #3: ffff88805ff2a210 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
 #4: ffff88803a28c1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
 #4: ffff88803a28c1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
3 locks held by kworker/0:1H/71:
 #0: ffff88813ff1b538 ((wq_completion)events_highpri){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88813ff1b538 ((wq_completion)events_highpri){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc9000154fc40 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc9000154fc40 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffffffff8f50da18 (clients_lock#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #2: ffffffff8f50da18 (clients_lock#2){+.+.}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:620 [inline]
 #2: ffffffff8f50da18 (clients_lock#2){+.+.}-{3:3}, at: client_use_ptr+0x4d/0xa90 sound/core/seq/seq_clientmgr.c:118
2 locks held by kworker/u8:12/3019:
 #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc9000e977c40 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc9000e977c40 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
2 locks held by kworker/u8:15/3514:
 #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc9000f3b7c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc9000f3b7c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
2 locks held by klogd/4953:
1 lock held by udevd/4964:
2 locks held by getty/5354:
 #0: ffff888035f540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:2/9516:
 #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc90003cdfc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc90003cdfc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffff88806de3f280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
5 locks held by kworker/u8:31/10763:
 #0: ffff8880600ef138 ((wq_completion)wg-kex-wg2#18){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff8880600ef138 ((wq_completion)wg-kex-wg2#18){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc900058ffc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc900058ffc40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffff8880356297b8 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x12e/0x810 drivers/net/wireguard/noise.c:529
 #3: ffff88805dd183f8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x13f/0x810 drivers/net/wireguard/noise.c:530
 #4: ffff8880b8636d10 ((crngs.lock)){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #4: ffff8880b8636d10 ((crngs.lock)){+.+.}-{3:3}, at: crng_make_state+0x158/0x5d0 drivers/char/random.c:358
3 locks held by syz.0.1912/13429:
 #0: ffff88802bc74328 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259
 #1: ffff888055464500 (sb_writers#20){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
 #1: ffff888055464500 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
 #2: ffffffff8e4e9538 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xb5/0xd20 fs/nfsd/nfsctl.c:860
2 locks held by syz-executor/13744:
 #0: ffff8880342680d0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff8880342680d0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
 #0: ffff8880342680d0 (&type->s_umount_key#83){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
 #1: ffffffff8e4e9538 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
2 locks held by syz-executor/13752:
 #0: ffff8880443a80d0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
 #0: ffff8880443a80d0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
 #0: ffff8880443a80d0 (&type->s_umount_key#83){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
 #1: ffffffff8e4e9538 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
3 locks held by kworker/1:6/13932:
 #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc9000e507c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc9000e507c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffff888020b9b280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
4 locks held by udevd/14034:
 #0: ffff888034da03d8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xa5/0xcb0 fs/seq_file.c:183
 #1: ffff88803b297878 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5d/0x420 fs/kernfs/file.c:165
 #2: ffff88805e298b48 (kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
 #2: ffff88805e298b48 (kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:166
 #3: ffff88805ff2a210 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1107 [inline]
 #3: ffff88805ff2a210 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
2 locks held by syz.8.2038/14633:
 #0: ffffffff8f623220 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8e4e9538 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_get_doit+0x11a/0x6a0 fs/nfsd/nfsctl.c:2114
16 locks held by kworker/u8:3/14773:
3 locks held by kworker/u8:9/14776:
 #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff88813ff5c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #1: ffffc9000486fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffffc9000486fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
 #2: ffff8880a74e08d8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6884 [inline]
 #2: ffff8880a74e08d8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420 net/wireless/core.c:524
6 locks held by kworker/u8:24/14782:
3 locks held by syz.6.2415/15973:
 #0: ffff8880379dab28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259
 #1: ffff888039688500 (sb_writers#20){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
 #1: ffff888039688500 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
 #2: ffffffff8e4e9538 (nfsd_mutex){+.+.}-{4:4}, at: write_versions+0x95/0xe30 fs/nfsd/nfsctl.c:701
9 locks held by syz-executor/16074:
4 locks held by syz.7.2507/16599:
2 locks held by modprobe/16607:
1 lock held by sed/16609:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17 Comm: pr/legacy Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:401
Code: e8 ee b8 6f fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 9f 2b d9 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000167a28 EFLAGS: 00000202
RAX: 1ffffffff33c9500 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff855611b0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff99e4ad40 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125d41000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe6fc6a5008 CR3: 000000003d440000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000cbe6 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:128 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
 wait_for_lsr+0x190/0x300 drivers/tty/serial/8250/8250_port.c:1982
 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3235 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3318 [inline]
 serial8250_console_write+0x12a2/0x1b40 drivers/tty/serial/8250/8250_port.c:3385
 console_emit_next_record kernel/printk/printk.c:3163 [inline]
 console_flush_one_record+0x642/0xb50 kernel/printk/printk.c:3269
 legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>