INFO: task syz.5.2054:11223 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2054      state:D stack:27200 pid:11223 tgid:11222 ppid:10979  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 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: 0033:0x7f29c039ce59
RSP: 002b:00007f29c1221028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f29c0615fa0 RCX: 00007f29c039ce59
RDX: 0000000004004990 RSI: 0000200000000040 RDI: 0000000000000003
RBP: 00007f29c0432e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f29c0616038 R14: 00007f29c0615fa0 R15: 00007ffcdc323ba8
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/1:0/24:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #1: ffffc900001e7c40 ((perf_sched_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #2: ffffffff8ea23f80 (perf_sched_mutex){+.+.}-{4:4}, at: perf_sched_delayed+0x18/0x70
 #3: ffffffff8e7e75f0 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_disable+0x12/0x20
 #4: ffff88823c624440 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xc9/0x320
1 lock held by khungtaskd/35:
 #0: ffffffff8e959c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5437:
 #0: ffff888111baf0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034762e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
2 locks held by syz.0.1805/10607:
 #0: ffffffff8fe5bae8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ec8eaa0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2b9/0xc30
2 locks held by syz.5.2054/11223:
 #0: ffffffff8fe5bae8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8ec8eaa0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790
3 locks held by syz.2.2851/13168:
 #0: ffffffff8fe5bae8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffff888011fc26e8 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xf4/0x7b0
 #2: ffffffff8ec8eaa0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_get_reqs_dumpit+0xf7/0xc40
1 lock held by syz-executor/14502:
3 locks held by syz.7.3838/15863:
 #0: ffffffff9a5098b8 (&pmus_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x2c/0x60
 #1: ffffffff8ea23f80 (perf_sched_mutex){+.+.}-{4:4}, at: account_event+0x753/0x870
 #2: ffffffff8e95ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770

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

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: 14502 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:check_preemption_disabled+0x29/0xe0
Code: 90 55 41 57 41 56 53 65 8b 05 f7 cd 8b 07 65 8b 0d ec cd 8b 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d e9 09 e3 02 00 cc 9c <59> f7 c1 00 02 00 00 74 ea 65 4c 8b 3d 9e cd 8b 07 41 f6 47 2f 04
RSP: 0018:ffffc900044ffca0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000287 RCX: 0000000080000000
RDX: 0000000000000004 RSI: ffffffff8dffacef RDI: ffffffff8c2a9f80
RBP: dffffc0000000000 R08: ffffffff821b739f R09: 0000000000000000
R10: 0000000000000000 R11: ffff8881b63f29f8 R12: ffff8881b63f29f8
R13: ffffffff821b739f R14: ffff8881b63f29f8 R15: ffff8881a9fb3b80
FS:  0000555585ede500(0000) GS:ffff8882a9224000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1362615fac CR3: 00000001acb1c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 lock_release+0xa1/0x3c0
 strncpy_from_user+0x31/0x2c0
 do_getname+0x77/0x250
 do_sys_openat2+0xcc/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f77f5d68e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffd2c35e548 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000555585ede500 RCX: 00007f9f77f5d68e
RDX: 0000000000000000 RSI: 00007ffd2c35e6b0 RDI: ffffffffffffff9c
RBP: 00007ffd2c35e6b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd2c35f7a0
R13: 00007f9f780322ca R14: 0000555585ede4e8 R15: 0000000000000007
 </TASK>
