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faux_driver vkms: [drm] vblank wait timed out on crtc 0
WARNING: drivers/gpu/drm/drm_vblank.c:1318 at drm_wait_one_vblank+0x2e8/0x5a0 drivers/gpu/drm/drm_vblank.c:1318, CPU#2: kworker/2:4/6027
Modules linked in:
CPU: 2 UID: 0 PID: 6027 Comm: kworker/2:4 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events drm_fb_helper_damage_work
RIP: 0010:drm_wait_one_vblank+0x2ee/0x5a0 drivers/gpu/drm/drm_vblank.c:1318
Code: 4c 8b 6d 50 4d 85 ed 0f 84 01 02 00 00 e8 0a 5b 6a fc 48 89 ef e8 c2 1e 92 00 48 89 c6 48 8d 3d 38 39 3e 0b 44 89 e1 4c 89 ea <67> 48 0f b9 3a e9 55 fe ff ff e8 e3 5a 6a fc 48 89 ef e8 5b 3e 26
RSP: 0018:ffffc9000404fa10 EFLAGS: 00010293
RAX: ffffffff8c221640 RBX: ffff888103756000 RCX: 0000000000000000
RDX: ffffffff8c201020 RSI: ffffffff8c221640 RDI: ffffffff9092c4b0
RBP: ffff888102f41000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880387354b0 R12: 0000000000000000
R13: ffffffff8c201020 R14: 1ffff92000809f45 R15: 000000000000564a
FS:  0000000000000000(0000) GS:ffff8880d6af5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000012c0 CR3: 0000000058595000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 drm_client_modeset_wait_for_vblank+0xef/0x120 drivers/gpu/drm/drm_client_modeset.c:1330
 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:334 [inline]
 drm_fb_helper_damage_work+0xbe/0x5e0 drivers/gpu/drm/drm_fb_helper.c:369
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
----------------
Code disassembly (best guess):
   0:	4c 8b 6d 50          	mov    0x50(%rbp),%r13
   4:	4d 85 ed             	test   %r13,%r13
   7:	0f 84 01 02 00 00    	je     0x20e
   d:	e8 0a 5b 6a fc       	call   0xfc6a5b1c
  12:	48 89 ef             	mov    %rbp,%rdi
  15:	e8 c2 1e 92 00       	call   0x921edc
  1a:	48 89 c6             	mov    %rax,%rsi
  1d:	48 8d 3d 38 39 3e 0b 	lea    0xb3e3938(%rip),%rdi        # 0xb3e395c
  24:	44 89 e1             	mov    %r12d,%ecx
  27:	4c 89 ea             	mov    %r13,%rdx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 55 fe ff ff       	jmp    0xfffffe89
  34:	e8 e3 5a 6a fc       	call   0xfc6a5b1c
  39:	48 89 ef             	mov    %rbp,%rdi
  3c:	e8                   	.byte 0xe8
  3d:	5b                   	pop    %rbx
  3e:	3e                   	ds
  3f:	26                   	es