INFO: task syz.7.4486:15282 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.4486      state:D stack:27888 pid:15282 ppid:12080  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
 write_versions+0x90/0xbb0 fs/nfsd/nfsctl.c:681
 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
 vfs_write+0x2dc/0x9a0 fs/read_write.c:582
 ksys_write+0x14d/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5ed4f9e199
RSP: 002b:00007f5ed5e1f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f5ed5225fa0 RCX: 00007f5ed4f9e199
RDX: 0000000000000015 RSI: 00002000000001c0 RDI: 0000000000000003
RBP: 00007f5ed50358e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ed5226038 R14: 00007f5ed5225fa0 R15: 00007ffd944bbac8
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2e230 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2ea50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2d8a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6669
2 locks held by getty/11802:
 #0: ffff88802f43f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900040fe2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
3 locks held by syz.4.4270/14748:
 #0: ffff888079734368 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
 #1: ffff888055512460 (sb_writers#27){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
 #2: ffffffff8cdccf08 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb3/0xb80 fs/nfsd/nfsctl.c:846
3 locks held by syz.7.4486/15282:
 #0: ffff88801da41768 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
 #1: ffff88804359c460 (sb_writers#27){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
 #2: ffffffff8cdccf08 (nfsd_mutex){+.+.}-{3:3}, at: write_versions+0x90/0xbb0 fs/nfsd/nfsctl.c:681
2 locks held by kworker/u4:8/16192:
 #0: ffff8880b8f3acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538
 #1: ffff8880b8f27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x400/0x740 kernel/sched/psi.c:999
3 locks held by syz.5.5105/16953:
2 locks held by syz.8.5151/17077:
1 lock held by syz.5.5154/17085:
 #0: ffff888025e271d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
 #0: ffff888025e271d8 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x16c/0x2d0 mm/util.c:518
1 lock held by syz.5.5154/17087:
1 lock held by syz.3.5160/17098:
2 locks held by dhcpcd/17100:
 #0: ffff88802837a130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff88802837a130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd40 net/packet/af_packet.c:3285
 #1: ffffffff8cb33578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #1: ffffffff8cb33578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 17077 Comm: syz.8.5151 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4827 [inline]
RIP: 0010:__lock_acquire+0xab4/0x7ea0 kernel/locking/lockdep.c:5121
Code: 3d b0 91 5f 15 00 0f 84 99 00 00 00 45 31 f6 4d 8d a6 c8 00 00 00 4c 89 e0 48 c1 e8 03 42 0f b6 04 00 84 c0 0f 85 24 01 00 00 <45> 0f b6 24 24 45 84 e4 74 3e 0f b6 84 24 88 00 00 00 41 0f b6 cc
RSP: 0018:ffffc900000078c0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffffffff81640f49
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90b33248
RBP: ffffc90000007b08 R08: dffffc0000000000 R09: 1ffffffff2166649
R10: dffffc0000000000 R11: fffffbfff216664a R12: ffffffff904a0308
R13: ffff8880197b2950 R14: ffffffff904a0240 R15: ffff8880197b2950
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8b80fef158 CR3: 000000002c1b5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x63/0x380 lib/debugobjects.c:810
 debug_hrtimer_deactivate kernel/time/hrtimer.c:453 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1719 [inline]
 __hrtimer_run_queues+0x2d8/0xc90 kernel/time/hrtimer.c:1815
 hrtimer_interrupt+0x399/0x980 kernel/time/hrtimer.c:1877
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:check_preemption_disabled+0x2e/0x110 lib/smp_processor_id.c:55
Code: 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 05 11 4b ce 75 65 8b 0d b2 a0 ce 75 f7 c1 ff ff ff 7f 74 1f <65> 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 48 83
RSP: 0018:ffffc900034175c8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8adf6dc0 RDI: ffffffff8adf6d80
RBP: ffffc90003417740 R08: ffffffff8e20d96f R09: 1ffffffff1c41b2d
R10: dffffc0000000000 R11: fffffbfff1c41b2e R12: 1ffff92000682ed0
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
 rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:721
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xe2/0x4a0 kernel/locking/lockdep.c:5761
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 page_ext_get+0x3a/0x2a0 mm/page_ext.c:157
 page_table_check_clear+0x4a/0x6b0 mm/page_table_check.c:71
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 zap_pte_range mm/memory.c:1433 [inline]
 zap_pmd_range mm/memory.c:1572 [inline]
 zap_pud_range mm/memory.c:1601 [inline]
 zap_p4d_range mm/memory.c:1622 [inline]
 unmap_page_range+0x1905/0x25b0 mm/memory.c:1643
 unmap_vmas+0x260/0x390 mm/memory.c:1728
 exit_mmap+0x20d/0x970 mm/mmap.c:3250
 __mmput+0x118/0x3a0 kernel/fork.c:1210
 exit_mm+0x24d/0x350 kernel/exit.c:572
 do_exit+0x958/0x2570 kernel/exit.c:874
 do_group_exit+0x229/0x2e0 kernel/exit.c:1030
 __do_sys_exit_group kernel/exit.c:1041 [inline]
 __se_sys_exit_group kernel/exit.c:1039 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1039
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0af359e199
Code: Unable to access opcode bytes at 0x7f0af359e16f.
RSP: 002b:00007ffeaaefa738 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0af359e199
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffeaaefa79c R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000008c
R13: 00000000000927c0 R14: 000000000009b9da R15: 00007ffeaaefa7f0
 </TASK>