FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 1, space 0, times 1
CPU: 0 UID: 0 PID: 807 Comm: kworker/0:2 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
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:73 [inline]
 should_fail_ex+0x410/0x560 lib/fault-inject.c:174
 should_failslab+0xa8/0x100 mm/failslab.c:46
 slab_pre_alloc_hook mm/slub.c:4638 [inline]
 slab_alloc_node mm/slub.c:4974 [inline]
 __kmalloc_cache_noprof+0xa3/0x600 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 drm_atomic_commit_alloc+0xa9/0x100 drivers/gpu/drm/drm_atomic.c:258
 drm_atomic_helper_dirtyfb+0x129/0xfd0 drivers/gpu/drm/drm_damage_helper.c:128
 drm_fbdev_shmem_helper_fb_dirty+0x160/0x310 drivers/gpu/drm/drm_fbdev_shmem.c:117
 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:339 [inline]
 drm_fb_helper_damage_work+0x84c/0xf20 drivers/gpu/drm/drm_fb_helper.c:365
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
------------[ 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+0x1e1/0x310 drivers/gpu/drm/drm_fbdev_shmem.c:118, CPU#0: kworker/0:2/807
Modules linked in:
CPU: 0 UID: 0 PID: 807 Comm: kworker/0:2 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+0x288/0x310 drivers/gpu/drm/drm_fbdev_shmem.c:118
Code: 29 fc 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 fa 21 9b fc 4d 8b 27 48 89 df 4c 89 f6 4c 89 e2 8b 5c 24 04 89 d9 <67> 48 0f b9 3a 89 d8 e9 f7 fe ff ff 89 d9 80 e1 07 fe c1 38 c1 0f
RSP: 0018:ffffc90004397898 EFLAGS: 00010246
RAX: 1ffff11003ed741a RBX: 00000000fffffff4 RCX: 00000000fffffff4
RDX: ffff88801f47b900 RSI: ffffffff8c79ae40 RDI: ffffffff90861ab0
RBP: ffff88801d294008 R08: 0000000000000dc0 R09: 00000000ffffffff
R10: dffffc0000000000 R11: fffffbfff1dd6087 R12: ffff88801f47b900
R13: dffffc0000000000 R14: ffffffff8c79ae40 R15: ffff88801f6ba0d0
FS:  0000000000000000(0000) GS:ffff88808c2cd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000050a84000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:339 [inline]
 drm_fb_helper_damage_work+0x84c/0xf20 drivers/gpu/drm/drm_fb_helper.c:365
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 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:	29 fc                	sub    %edi,%esp
   2:	4c 89 f8             	mov    %r15,%rax
   5:	48 c1 e8 03          	shr    $0x3,%rax
   9:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
   e:	74 08                	je     0x18
  10:	4c 89 ff             	mov    %r15,%rdi
  13:	e8 fa 21 9b fc       	call   0xfc9b2212
  18:	4d 8b 27             	mov    (%r15),%r12
  1b:	48 89 df             	mov    %rbx,%rdi
  1e:	4c 89 f6             	mov    %r14,%rsi
  21:	4c 89 e2             	mov    %r12,%rdx
  24:	8b 5c 24 04          	mov    0x4(%rsp),%ebx
  28:	89 d9                	mov    %ebx,%ecx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	89 d8                	mov    %ebx,%eax
  31:	e9 f7 fe ff ff       	jmp    0xffffff2d
  36:	89 d9                	mov    %ebx,%ecx
  38:	80 e1 07             	and    $0x7,%cl
  3b:	fe c1                	inc    %cl
  3d:	38 c1                	cmp    %al,%cl
  3f:	0f                   	.byte 0xf