INFO: task syz.3.421:7452 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.421       state:D stack:25296 pid:7452  tgid:7450  ppid:7244   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1360
 nfsd_nl_rpc_status_get_dumpit+0xdf/0x1290
 genl_dumpit+0x10b/0x1b0
 netlink_dump+0x6e4/0xe90
 __netlink_dump_start+0x5cb/0x7e0
 genl_family_rcv_msg_dumpit+0x1e7/0x2c0
 genl_rcv_msg+0x5da/0x790
 netlink_rcv_skb+0x208/0x470
 genl_rcv+0x28/0x40
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f153b78ebe9
RSP: 002b:00007f153c5c1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f153b9c6090 RCX: 00007f153b78ebe9
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000008
RBP: 00007f153b811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f153b9c6128 R14: 00007f153b9c6090 R15: 00007ffca7377b48
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ea0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5672:
 #0: ffff88810ce0a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
3 locks held by kworker/u8:4/5915:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000451fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8e13f800 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570
2 locks held by syz.1.407/7358:
 #0: ffffffff8f59d470 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8e418588 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960
3 locks held by syz.3.421/7452:
 #0: ffffffff8f59d470 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffff88803b92d6d0 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0
 #2: ffffffff8e418588 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdf/0x1290
1 lock held by syz.5.512/7877:
 #0: ffff888024434260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28e/0xb50
1 lock held by syz.5.523/7911:
 #0: ffff8880287ac260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28e/0xb50
1 lock held by syz.4.525/7916:
 #0: ffff8880287ab7a0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28e/0xb50
3 locks held by syz.7.1523/11442:

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

NMI backtrace for cpu 1
CPU: 1 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11442 Comm: syz.7.1523 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:native_apic_msr_write+0x39/0x50
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 cc cc cc cc cc f3 0f 1e fa 89 f6 31 d2 e9 92 65 8e 03 66
RSP: 0018:ffffc90000007e50 EFLAGS: 00000046
RAX: 00000000000001e5 RBX: ffff88804b023900 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 00000000000001e5 RDI: 0000000000000838
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81ae033e
R10: 0000000000000003 R11: ffffffff81703490 R12: 0000000010000a10
R13: dffffc0000000000 R14: 00000000000001e5 R15: 0000000000000020
FS:  00007fe8184896c0(0000) GS:ffff8880b861c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560ee55a1f10 CR3: 000000003fd8e000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lapic_next_event+0x11/0x20
 clockevents_program_event+0x1cf/0x360
 hrtimer_interrupt+0x620/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__local_bh_enable_ip+0x135/0x1c0
Code: 8b e8 9f 7a f4 09 65 66 8b 05 4f 58 1b 11 66 85 c0 75 5a bf 01 00 00 00 e8 58 15 0b 00 e8 e3 6d 42 00 fb 65 8b 05 2b 58 1b 11 <85> c0 75 05 e8 e2 de ae ff 48 c7 04 24 0e 36 e0 45 4b c7 04 37 00
RSP: 0018:ffffc90002a0f920 EFLAGS: 00000282
RAX: 0000000080000000 RBX: 0000000000000200 RCX: 158cb12e90862000
RDX: 0000000000000000 RSI: ffffffff8d9b6a5f RDI: ffffffff8be33300
RBP: ffffc90002a0f9b0 R08: ffffffff8fa38037 R09: 1ffffffff1f47006
R10: dffffc0000000000 R11: fffffbfff1f47007 R12: ffffffff89a280d7
R13: ffffc90002446030 R14: dffffc0000000000 R15: 1ffff92000541f24
 bpf_test_run+0x376/0x7b0
 bpf_prog_test_run_skb+0xb30/0x1560
 bpf_prog_test_run+0x2c7/0x340
 __sys_bpf+0x581/0x870
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe81758ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe818489038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fe8177c6090 RCX: 00007fe81758ebe9
RDX: 0000000000000050 RSI: 0000200000000340 RDI: 000000000000000a
RBP: 00007fe817611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe8177c6128 R14: 00007fe8177c6090 R15: 00007fff3e9f52f8
 </TASK>
