INFO: task syz.3.4690:23382 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.4690      state:D stack:25608 pid:23382 tgid:23379 ppid:18951  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 sync_bdevs+0x1ac/0x340
 ksys_sync+0xb9/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0969b8ec29
RSP: 002b:00007f096aa9c038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f0969dd5fa0 RCX: 00007f0969b8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f0969dd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0969dd6038 R14: 00007f0969dd5fa0 R15: 00007ffee8be11a8
 </TASK>
INFO: task syz.3.4690:23384 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.4690      state:D stack:25896 pid:23384 tgid:23379 ppid:18951  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 sync_bdevs+0x1ac/0x340
 ksys_sync+0xb9/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0969b8ec29
RSP: 002b:00007f096aa7b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f0969dd6090 RCX: 00007f0969b8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f0969dd6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0969dd6128 R14: 00007f0969dd6090 R15: 00007ffee8be11a8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e33d320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5676:
 #0: ffff888021ed20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000290e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by udevd/6089:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.3.4690/23382:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.3.4690/23384:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
2 locks held by kworker/u10:33/23663:
1 lock held by syz.8.5491/26217:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26219:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26223:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26226:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26230:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26233:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26234:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.8.5491/26236:
 #0: ffff88810a010358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
5 locks held by syz.2.5601/26668:
1 lock held by syz.7.5604/26673:
 #0: ffff88813663a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140

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

NMI backtrace for cpu 0
CPU: 0 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 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: 26673 Comm: syz.7.5604 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:trace_irq_disable+0x16/0x110
Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 56 53 66 90 65 8b 05 68 2d fa 10 83 f8 08 73 3c 89 c3 c1 e8 06 <48> 8d 3c c5 70 57 c3 8f be 08 00 00 00 e8 48 ec 5d 00 48 0f a3 1d
RSP: 0000:ffffc90006c9f8a8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 2d5b442e60b1bc00
RDX: 0000000000000007 RSI: ffffffff8db9fb03 RDI: ffffffff8b823462
RBP: ffffc90006c9f958 R08: ffffffff8fc35777 R09: 1ffffffff1f86aee
R10: dffffc0000000000 R11: fffffbfff1f86aef R12: dffffc0000000000
R13: ffff88812be00000 R14: 0000000000000a06 R15: 1ffff92000d93f18
FS:  00007f8c01e7d6c0(0000) GS:ffff8881a39fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000ff4000 CR3: 000000011c5b8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 _raw_spin_lock_irqsave+0x82/0xf0
 debug_check_no_obj_freed+0x17a/0x470
 __free_frozen_pages+0x4dd/0xd30
 __folio_put+0x21b/0x2c0
 do_huge_pmd_anonymous_page+0x844/0xb60
 __handle_mm_fault+0x1139/0x5400
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0xa7c/0x1380
 exc_page_fault+0x82/0x100
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f8c00e4ea86
Code: 01 14 00 8b 75 00 ba 03 00 00 00 45 89 e0 49 89 45 00 41 b9 00 00 00 10 b9 01 80 00 00 31 ff c1 e6 06 e8 cd 01 14 00 8b 55 40 <49> 89 07 49 03 55 00 45 85 f6 74 1b 44 89 f3 31 c0 66 0f 1f 84 00
RSP: 002b:00007f8c01e7cfd0 EFLAGS: 00010207
RAX: 00007f8bfeff7000 RBX: 00007f8c011d5fa0 RCX: 00007f8c00f8ec63
RDX: 0000000000100040 RSI: 0000000000200000 RDI: 0000000000000000
RBP: 0000200000000000 R08: 0000000000000004 R09: 0000000010000000
R10: 0000000000008001 R11: 0000000000000246 R12: 0000000000000004
R13: 0000200000000100 R14: 00000000000050d0 R15: 0000200000ff4000
 </TASK>
vkms_vblank_simulate: vblank timer overrun
