INFO: task syz.3.2115:12726 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2115      state:D stack:24296 pid:12726 tgid:12725 ppid:10779  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 nfsd_nl_version_get_doit+0x17c/0xc40
 genl_family_rcv_msg_doit+0x22a/0x330
 genl_rcv_msg+0x61c/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 ____sys_sendmsg+0x972/0x9f0
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5fc39c799
RSP: 002b:00007fd5fd325028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd5fc615fa0 RCX: 00007fd5fc39c799
RDX: 0000000020048000 RSI: 0000200000000140 RDI: 0000000000000009
RBP: 00007fd5fc432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd5fc616038 R14: 00007fd5fc615fa0 R15: 00007ffee6d9a588
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5636:
 #0: ffff88810efae0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900017782f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by sshd/5802:
6 locks held by kworker/u8:2/5834:
 #0: ffff8881012ae148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc900066cfc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8fbc03d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffff88816dbf6130 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x11b/0x3f0
 #4: ffff88816dbf0250 (&devlink->lock_key#9){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x12d/0x3f0
 #5: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0
3 locks held by kworker/u8:4/5885:
 #0: ffff888176b0a948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc90006a9fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0
2 locks held by syz.2.1418/10347:
 #0: ffffffff8fc3c8b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ea862c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670
2 locks held by syz.3.2115/12726:
 #0: ffffffff8fc3c8b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ea862c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x17c/0xc40
2 locks held by syz.4.2659/14649:
 #0: ffffffff8fc3c8b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ea862c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_get_doit+0x10a/0x5e0
2 locks held by syz.1.3524/17502:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
 #1: ffffffff8e764878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by syz.0.3527/17520:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newroute+0x12b/0x250
2 locks held by syz.8.3535/17540:
 #0: ffff8881bf95e4d8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100
 #1: ffffffff8e764878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17540 Comm: syz.8.3535 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:lock_release+0xa8/0x3d0
Code: 00 0f 85 f7 01 00 00 49 81 3e 20 34 e0 93 0f 84 ea 01 00 00 9c 5b fa 48 c7 c7 a2 24 f1 8d e8 4f 31 0d 0a 65 ff 05 38 e9 7a 11 <c7> 44 24 24 01 00 00 00 83 3d 39 2b 70 0e 00 0f 84 90 01 00 00 41
RSP: 0018:ffffc9000890ef30 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000202 RCX: 0000000000000046
RDX: ffffc9000890f001 RSI: ffffffff8df124a2 RDI: ffffffff8c27ca00
RBP: dffffc0000000000 R08: ffffc9000890f788 R09: 0000000000000000
R10: ffffc9000890f0b8 R11: fffff52001121e19 R12: ffffc9000890f798
R13: ffffffff81767e95 R14: ffffffff8e75e5e0 R15: ffff88816ca7ba80
FS:  00007f493cef06c0(0000) GS:ffff8882a945a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005564d9fefe38 CR3: 0000000110ff6000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 unwind_next_frame+0x1aaa/0x23c0
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 free_unref_folios+0xed5/0x16d0
 folios_put_refs+0x789/0x8d0
 free_pages_and_swap_cache+0x2e7/0x5b0
 tlb_flush_mmu+0x6d3/0xa30
 tlb_finish_mmu+0xf9/0x230
 exit_mmap+0x498/0xa10
 __mmput+0x118/0x430
 exit_mm+0x168/0x220
 do_exit+0x6a2/0x23c0
 do_group_exit+0x21b/0x2d0
 get_signal+0x1284/0x1330
 arch_do_signal_or_restart+0xbc/0x830
 exit_to_user_mode_loop+0x86/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f493bf9c799
Code: Unable to access opcode bytes at 0x7f493bf9c76f.
RSP: 002b:00007f493cef0028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 00000000000000a8 RBX: 00007f493c215fa0 RCX: 00007f493bf9c799
RDX: 0000000000000080 RSI: 0000200000000c40 RDI: 0000000000000004
RBP: 00007f493c032c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f493c216038 R14: 00007f493c215fa0 R15: 00007fffda8273d8
 </TASK>
