INFO: task syz.7.1742:11490 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1742      state:D stack:27880 pid:11490 ppid:9620   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5393 [inline]
 __schedule+0x156f/0x4720 kernel/sched/core.c:6722
 schedule+0xbd/0x170 kernel/sched/core.c:6796
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6855
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x689/0xce0 kernel/locking/mutex.c:747
 write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843
 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113
 vfs_write+0x299/0x9a0 fs/read_write.c:582
 ksys_write+0x151/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7d7079fb19
RSP: 002b:00007f7d71621028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7d70a25fa0 RCX: 00007f7d7079fb19
RDX: 0000000000000002 RSI: 0000200000000700 RDI: 0000000000000003
RBP: 00007f7d70837b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7d70a26038 R14: 00007f7d70a25fa0 R15: 00007ffd17a7d238
 </TASK>
INFO: task syz.8.1782:11563 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1782      state:D stack:27880 pid:11563 ppid:11274  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5393 [inline]
 __schedule+0x156f/0x4720 kernel/sched/core.c:6722
 schedule+0xbd/0x170 kernel/sched/core.c:6796
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6855
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x689/0xce0 kernel/locking/mutex.c:747
 nfsd4_write_time+0xae/0x740 fs/nfsd/nfsctl.c:984
 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113
 vfs_write+0x299/0x9a0 fs/read_write.c:582
 ksys_write+0x151/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe9bd59fb19
RSP: 002b:00007fe9be470028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe9bd825fa0 RCX: 00007fe9bd59fb19
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fe9bd637b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe9bd826038 R14: 00007fe9bd825fa0 R15: 00007fff99aecdf8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8e1322e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8e1322e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8e1322e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6669
2 locks held by getty/5542:
 #0: ffff888033b6a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000327e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x43a/0x1400 drivers/tty/n_tty.c:2217
2 locks held by syz-executor/5774:
1 lock held by udevd/5792:
 #0: ffff888022d244c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:801
3 locks held by kworker/u4:19/5935:
 #0: ffff888018c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #0: ffff888018c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #1: ffffc90004c27d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
 #1: ffffc90004c27d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
 #2: ffffffff8e137b80 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4089
3 locks held by syz.1.1502/10836:
 #0: ffff888065c3a5c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
 #1: ffff8880330fe418 (sb_writers#31){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580
 #2: ffffffff8e3e1b88 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843
3 locks held by syz.7.1742/11490:
 #0: ffff88802ceefc48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
 #1: ffff88805d1fc418 (sb_writers#31){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580
 #2: ffffffff8e3e1b88 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843
3 locks held by syz.8.1782/11563:
 #0: ffff8880269d4ac8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
 #1: ffff88807b69c418 (sb_writers#31){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580
 #2: ffffffff8e3e1b88 (nfsd_mutex){+.+.}-{3:3}, at: nfsd4_write_time+0xae/0x740 fs/nfsd/nfsctl.c:984
3 locks held by syz.9.2318/13517:
 #0: ffff88803062e848 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
 #1: ffff888057092418 (sb_writers#31){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580
 #2: ffffffff8e3e1b88 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843
2 locks held by dhcpcd-run-hook/14998:

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf59/0xfa0 kernel/hung_task.c:379
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5935 Comm: kworker/u4:19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:in_lock_functions+0x4/0x20 kernel/locking/spinlock.c:412
Code: 03 38 c1 0f 8c 77 ff ff ff 48 c7 c7 80 3a 26 94 e8 81 c7 76 00 e9 66 ff ff ff cc cc cc cc cc cc cc cc cc cc cc cc f3 0f 1e fa <48> 81 ff 10 90 a1 8a 0f 93 c0 48 81 ff 5f bb a1 8a 0f 92 c1 20 c1
RSP: 0018:ffffc90004c27ac8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff8aa19112 RCX: ffffffff9832a403
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8aa19112
RBP: ffff88801d340000 R08: ffff8880323a803f R09: 1ffff11006475007
R10: dffffc0000000000 R11: ffffed1006475008 R12: ffff88805dbd9400
R13: ffff88805dbd95d8 R14: dffffc0000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcc6091398 CR3: 000000000df32000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 get_lock_parent_ip include/linux/ftrace.h:977 [inline]
 preempt_latency_start kernel/sched/core.c:5839 [inline]
 preempt_count_add+0x91/0x1a0 kernel/sched/core.c:5864
 __raw_spin_lock include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock+0x12/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:791 [inline]
 nsim_dev_trap_report_work+0x190/0xa90 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>