INFO: task syz.9.11274:1763 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.11274     state:D stack:26792 pid:1763  tgid:1762  ppid:1164   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 nfsd_nl_threads_get_doit+0x1c0/0x790
 genl_family_rcv_msg_doit+0x233/0x340
 genl_rcv_msg+0x614/0x7a0
 netlink_rcv_skb+0x226/0x4a0
 genl_rcv+0x28/0x40
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 ____sys_sendmsg+0x54e/0x850
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1b1/0x290
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd30cd9ce59
RSP: 002b:00007fd30dce9028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd30d015fa0 RCX: 00007fd30cd9ce59
RDX: 0000000004004990 RSI: 0000200000000040 RDI: 0000000000000006
RBP: 00007fd30ce32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd30d016038 R14: 00007fd30d015fa0 R15: 00007ffd52f583d8
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 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/0x380
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 7329 Comm: dhcpcd-run-hook 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:_raw_spin_unlock_irqrestore+0x47/0x80
Code: f7 e8 ed 4a f1 f5 f7 c3 00 02 00 00 74 05 e8 b0 2f 1d f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 04 61 e2 f5 65 8b 05 9d b2 8b 07 85 c0 74 18 5b 41 5e e9 81 48
RSP: 0018:ffffc90004c978a0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000286 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8c2a8d60 RDI: 0000000000000001
RBP: ffff8881732aacc0 R08: ffffffff9031b4f7 R09: 1ffffffff206369e
R10: dffffc0000000000 R11: fffffbfff206369f R12: ffffffff8bce1830
R13: ffff8881732aacb0 R14: ffffffff9a68d0d8 R15: 1ffff1102e655598
FS:  00007fc0730c0380(0000) GS:ffff8882a9251000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560e54984a18 CR3: 000000000e746000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 debug_object_activate+0x2dd/0x410
 call_rcu+0x43/0x8b0
 kmem_cache_free+0x462/0x650
 tear_down_vmas+0x312/0x520
 exit_mmap+0x4ca/0x9f0
 __mmput+0x118/0x420
 exit_mm+0x221/0x2d0
 do_exit+0x6cd/0x2360
 do_group_exit+0x22d/0x2f0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x221a/0x2240
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc0731faa90
Code: Unable to access opcode bytes at 0x7fc0731faa66.
RSP: 002b:00007ffdf2930bb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000560e5496e910 RCX: 00007fc0731faa90
RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00007ffdf2930ee8 R08: 0000560e5496ec58 R09: aa5beccfda63b370
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdf2930ee0
R13: 00007ffdf2930ef0 R14: 0000560e28058169 R15: 00007fc0733f9a80
 </TASK>
