INFO: task syz.0.19451:27552 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.19451     state:D stack:28200 pid:27552 tgid:27550 ppid:5667   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1840/0x57a0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c5/0x1590
 kvm_vm_ioctl_set_mem_attributes+0x33c/0x1600
 kvm_vm_ioctl+0xb33/0xd30
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd90fb9de99
RSP: 002b:00007fd910a53028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd90fe26090 RCX: 00007fd90fb9de99
RDX: 00002000000000c0 RSI: 000000004020aed2 RDI: 000000000000000b
RBP: 00007fd90fc33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd90fe26128 R14: 00007fd90fe26090 R15: 00007fff582eba68
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8eb61600 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5444:
 #0: ffff8881026f00a0 (&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/0x1380
1 lock held by sshd/5603:
1 lock held by syz-executor/5672:
 #0: ffff888110b74ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0
1 lock held by syz.0.19451/27551:
1 lock held by syz.0.19451/27552:
 #0: ffff88810abe00a0 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vm_ioctl_set_mem_attributes+0x33c/0x1600
2 locks held by kworker/1:3/27967:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
 #1: ffffc90007c5fc40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0
2 locks held by syz.3.20731/32008:
 #0: ffff888118b50ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0
 #1: ffffffff8eb67928 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by kvm-nx-lpage-re/32010:
 #0: ffffffff8eb67928 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by syz.2.20733/32014:
 #0: ffffffff8eb677f8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 kthread+0x389/0x470
 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: 32010 Comm: kvm-nx-lpage-re 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:kasan_check_range+0x97/0x2c0
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 9e 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd
RSP: 0018:ffffc9000174f978 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff82259a2e
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9054d130
RBP: ffffea000072aa40 R08: ffffffff9054d137 R09: 1ffffffff20a9a26
R10: dffffc0000000000 R11: fffffbfff20a9a26 R12: 0000000000000001
R13: 1ffffd40000e5549 R14: fffffbfff20a9a27 R15: 1ffffffff20a9a26
FS:  0000000000000000(0000) GS:ffff88818d9c9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd17f122000 CR3: 000000010f205000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000001 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 trace_mm_page_free+0x2e/0x160
 __free_frozen_pages+0x135/0xd20
 vfree+0x1fd/0x330
 kcov_close+0x28/0x50
 __fput+0x418/0xa50
 task_work_run+0x1d9/0x270
 do_exit+0x73a/0x2360
 vhost_task_fn+0x47f/0x4b0
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
