INFO: task syz.3.2618:15789 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2618      state:D stack:27112 pid:15789 tgid:15788 ppid:10533  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 nfsd_nl_listener_set_doit+0x141/0x1670
 genl_family_rcv_msg_doit+0x22a/0x330
 genl_rcv_msg+0x61c/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x75c/0x8e0
 netlink_sendmsg+0x813/0xb40
 ____sys_sendmsg+0x972/0x9f0
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8dfd79cdd9
RSP: 002b:00007f8dfe5c6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8dfda15fa0 RCX: 00007f8dfd79cdd9
RDX: 0000000004000000 RSI: 0000200000000100 RDI: 0000000000000004
RBP: 00007f8dfd832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8dfda16038 R14: 00007f8dfda15fa0 R15: 00007ffddce3d0b8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by syslogd/5041:
 #0: ffff88812103aea0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150
 #1: ffff888121024588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
2 locks held by getty/5439:
 #0: ffff8881125630a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
2 locks held by syz.1.1086/10002:
 #0: ffffffff8fe3f0e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ec8aca0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670
2 locks held by syz.3.2618/15789:
 #0: ffffffff8fe3f0e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ec8aca0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670
2 locks held by syz.2.4264/21907:
 #0: ffffffff8fe3f0e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8e7f9ae8 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xfc/0x2c0

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

NMI backtrace for cpu 1
CPU: 1 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/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 5598 Comm: syz-executor 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:dequeue_entities+0xa24/0x3aa0
Code: 3c 24 48 89 d8 48 c1 e8 03 80 3c 28 00 74 08 48 89 df e8 5f 68 99 00 49 89 5f 48 4d 8d 77 50 4c 89 f0 48 c1 e8 03 80 3c 28 00 <74> 08 4c 89 f7 e8 42 68 99 00 49 89 1e 4c 8b 74 24 20 4d 8d 65 10
RSP: 0018:ffffc900047cf578 EFLAGS: 00000046
RAX: 1ffff1102d02277a RBX: ffff888168113bc8 RCX: ffff888168113b00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888168113bd0
RBP: dffffc0000000000 R08: ffff888102af819c R09: 1ffffffff206163e
R10: dffffc0000000000 R11: fffffbfff206163f R12: ffff88812103ba78
R13: ffff88812103af00 R14: ffff888168113bd0 R15: ffff888168113b80
FS:  000055558fa71540(0000) GS:ffff88818dc8d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33e10ff8 CR3: 0000000102f20000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 pick_next_entity+0xcc8/0xe90
 pick_task_fair+0xca/0x260
 pick_next_task_fair+0x173/0x1ab0
 __pick_next_task+0xe6/0x480
 __schedule+0x974/0x5680
 schedule+0x164/0x360
 do_nanosleep+0x1c2/0x620
 hrtimer_nanosleep+0x18f/0x3a0
 __se_sys_clock_nanosleep+0x35b/0x3b0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f672d557f57
Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fffc4334bd0 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055558fa71540 RCX: 00007f672d557f57
RDX: 00007fffc4334c10 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fffc43350f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007fffc4334c4c R14: 00007fffc4334ce0 R15: 0000000000000000
 </TASK>
