node 0: slabs: 623, objs: 9968, free: 3
  node 1: slabs: 776, objs: 12416, free: 65
------------[ cut here ]------------
virtio-pci 0000:00:01.0: [drm] Dirty helper failed: ret=-12
WARNING: drivers/gpu/drm/drm_fbdev_shmem.c:118 at drm_fbdev_shmem_helper_fb_dirty+0x28d/0x350 drivers/gpu/drm/drm_fbdev_shmem.c:118, CPU#2: kworker/2:1/63
Modules linked in:
CPU: 2 UID: 0 PID: 63 Comm: kworker/2:1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: events drm_fb_helper_damage_work
RIP: 0010:drm_fbdev_shmem_helper_fb_dirty+0x292/0x350 drivers/gpu/drm/drm_fbdev_shmem.c:118
Code: 85 b5 00 00 00 4c 8b 65 50 4d 85 e4 74 51 e8 55 fc 24 fc 48 89 ef e8 8d 92 90 00 48 89 c6 48 8d 3d 43 e1 8b 0c 89 d9 4c 89 e2 <67> 48 0f b9 3a e9 41 ff ff ff e8 bf 11 9e fc e9 cb fd ff ff 48 89
RSP: 0018:ffffc90000d17b38 EFLAGS: 00010293
RAX: ffffffff8c925240 RBX: 00000000fffffff4 RCX: 00000000fffffff4
RDX: ffff88802465d000 RSI: ffffffff8c925240 RDI: ffffffff92750210
RBP: ffff8880248120d0 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000fffffff4 R11: 000000000000774b R12: ffff88802465d000
R13: ffffffff85eb98c0 R14: ffff888027744936 R15: ffff888027744934
FS:  0000000000000000(0000) GS:ffff8880d469e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7dfcc64ff8 CR3: 000000005400e000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 drm_fb_helper_fb_dirty drivers/gpu/drm/clients/drm_fbdev_helper.c:310 [inline]
 drm_fb_helper_damage_work+0x4c8/0xab0 drivers/gpu/drm/clients/drm_fbdev_helper.c:336
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3495
 process_scheduled_works kernel/workqueue.c:3578 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3659
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	85 b5 00 00 00 4c    	test   %esi,0x4c000000(%rbp)
   6:	8b 65 50             	mov    0x50(%rbp),%esp
   9:	4d 85 e4             	test   %r12,%r12
   c:	74 51                	je     0x5f
   e:	e8 55 fc 24 fc       	call   0xfc24fc68
  13:	48 89 ef             	mov    %rbp,%rdi
  16:	e8 8d 92 90 00       	call   0x9092a8
  1b:	48 89 c6             	mov    %rax,%rsi
  1e:	48 8d 3d 43 e1 8b 0c 	lea    0xc8be143(%rip),%rdi        # 0xc8be168
  25:	89 d9                	mov    %ebx,%ecx
  27:	4c 89 e2             	mov    %r12,%rdx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 41 ff ff ff       	jmp    0xffffff75
  34:	e8 bf 11 9e fc       	call   0xfc9e11f8
  39:	e9 cb fd ff ff       	jmp    0xfffffe09
  3e:	48                   	rex.W
  3f:	89                   	.byte 0x89