INFO: task syz.9.8013:27368 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.8013      state:D stack:27592 pid:27368 tgid:27367 ppid:23190  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 write_versions+0x95/0xe30
 nfsctl_transaction_write+0x10f/0x160
 vfs_write+0x296/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11dc79e159
RSP: 002b:00007f11dd5ca028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f11dca25fa0 RCX: 00007f11dc79e159
RDX: 0000000000000006 RSI: 00002000000001c0 RDI: 0000000000000003
RBP: 00007f11dc83506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f11dca26038 R14: 00007f11dca25fa0 R15: 00007ffe8998d5a8
 </TASK>
INFO: task syz.9.8013:27371 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.8013      state:D stack:28424 pid:27371 tgid:27367 ppid:23190  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 write_threads+0x39d/0x5a0
 nfsctl_transaction_write+0x10f/0x160
 vfs_write+0x296/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11dc79e159
RSP: 002b:00007f11dd5a9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f11dca26090 RCX: 00007f11dc79e159
RDX: 0000000000000002 RSI: 00002000000002c0 RDI: 0000000000000004
RBP: 00007f11dc83506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f11dca26128 R14: 00007f11dca26090 R15: 00007ffe8998d5a8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5427:
 #0: ffff888177a760a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
4 locks held by kworker/u9:18/11917:
 #0: ffff88812103b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160
 #1: ffff888121024440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0
 #2: ffff888121026058 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0
 #3: ffffffff9a9b8db0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xb7/0x420
5 locks held by kworker/u9:21/11920:
 #0: ffff88812103b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160
 #1: ffff888121024440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0
 #2: ffff888121026058 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0
 #3: ffffffff9a98dc58 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xb7/0x420
 #4: ffffffff8e9fd1a0 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30
2 locks held by syz-executor/23708:
 #0: ffff88811f1b20d8 (&type->s_umount_key#123){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ee8da80 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0
3 locks held by syz.4.7067/24882:
 #0: ffff88811faba2f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320
 #1: ffff888177b80450 (sb_writers#41){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0
 #2: ffffffff8ee8da80 (nfsd_mutex){+.+.}-{4:4}, at: write_threads+0x39d/0x5a0
3 locks held by syz.9.8013/27368:
 #0: ffff8881725134f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320
 #1: ffff888168a8a450 (sb_writers#41){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0
 #2: ffffffff8ee8da80 (nfsd_mutex){+.+.}-{4:4}, at: write_versions+0x95/0xe30
3 locks held by syz.9.8013/27371:
 #0: ffff88816c6decf0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320
 #1: ffff888168a8a450 (sb_writers#41){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0
 #2: ffffffff8ee8da80 (nfsd_mutex){+.+.}-{4:4}, at: write_threads+0x39d/0x5a0

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5525 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:cpuacct_charge+0x1b3/0x320
Code: f3 b3 95 00 4d 8b 65 00 eb 04 4d 8b 24 24 4d 85 e4 0f 84 91 00 00 00 4d 8d ac 24 70 01 00 00 4c 89 e8 48 c1 e8 03 80 3c 28 00 <74> 08 4c 89 ef e8 c3 b3 95 00 4d 8b 6d 00 41 83 fe 08 73 59 41 80
RSP: 0018:ffffc9000451f760 EFLAGS: 00000046
RAX: 1ffffffff1d434ce RBX: 0000000000062473 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8e4ac6af RDI: ffffffff8c4bb580
RBP: dffffc0000000000 R08: ffffffff90575937 R09: 1ffffffff20aeb26
R10: dffffc0000000000 R11: fffffbfff20aeb27 R12: ffffffff8ea1a500
R13: ffffffff8ea1a670 R14: 0000000000000000 R15: 1ffffffff1c9eafa
FS:  000055555a969540(0000) GS:ffff88818d959000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f86589ed158 CR3: 0000000114be2000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 update_se+0x2e9/0x1020
 update_curr+0x6c/0x440
 dequeue_entities+0x1af/0x3bd0
 dequeue_task_fair+0xc1/0x3d0
 __schedule+0x6e1/0x56c0
 schedule+0x164/0x2b0
 do_nanosleep+0x21e/0x6a0
 hrtimer_nanosleep+0x18f/0x3a0
 __se_sys_clock_nanosleep+0x35b/0x3b0
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3a749592d7
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:00007fff5c7aad60 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055555a969540 RCX: 00007f3a749592d7
RDX: 00007fff5c7aada0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff5c7ab280 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007fff5c7aaddc R14: 00007fff5c7aae70 R15: 0000000000000000
 </TASK>
