------------[ cut here ]------------
WARNING: CPU: 0 PID: 8284 at drivers/gpu/drm/drm_prime.c:223 drm_prime_destroy_file_private+0x43/0x60 drivers/gpu/drm/drm_prime.c:223
Modules linked in:
CPU: 0 UID: 0 PID: 8284 Comm: syz.1.506 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:drm_prime_destroy_file_private+0x43/0x60 drivers/gpu/drm/drm_prime.c:223
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 21 48 8b 83 90 00 00 00 48 85 c0 75 06 5b e9 93 88 76 fc e8 8e 88 76 fc 90 <0f> 0b 90 5b e9 84 88 76 fc e8 bf 1f de fc eb d8 66 66 2e 0f 1f 84
RSP: 0018:ffffc9000d487cb0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88801360f380 RCX: ffffffff8b5e8b01
RDX: ffff8880246e2480 RSI: ffffffff8545e4c2 RDI: ffff88801360f410
RBP: ffff88801360f000 R08: 0000000000000001 R09: fffff52001a90f76
R10: ffffc9000d487bb7 R11: 0000000000000000 R12: ffff8880440c4000
R13: ffff88801360f2b0 R14: 0000000000000000 R15: ffff88801360f2d8
FS:  0000000000000000(0000) GS:ffff888097810000(0063) knlGS:0000000057e05440
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000000c4137d0 CR3: 0000000027c3f000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 drm_file_free.part.0+0x7ee/0xcd0 drivers/gpu/drm/drm_file.c:269
 drm_file_free drivers/gpu/drm/drm_file.c:237 [inline]
 drm_close_helper.isra.0+0x186/0x1f0 drivers/gpu/drm/drm_file.c:290
 drm_release+0x1ab/0x360 drivers/gpu/drm/drm_file.c:438
 __fput+0x402/0xb70 fs/file_table.c:468
 task_work_run+0x150/0x240 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x130 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 __do_fast_syscall_32+0x240/0x300 arch/x86/entry/syscall_32.c:309
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f53579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ff82aedc EFLAGS: 00000202 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 000000000000001e
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi