------------[ cut here ]------------
WARNING: CPU: 0 PID: 7040 at drivers/gpu/drm/vkms/vkms_crtc.c:97 vkms_get_vblank_timestamp+0x137/0x160 drivers/gpu/drm/vkms/vkms_crtc.c:97
Modules linked in:
CPU: 0 UID: 0 PID: 7040 Comm: syz.4.301 Not tainted 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:vkms_get_vblank_timestamp+0x137/0x160 drivers/gpu/drm/vkms/vkms_crtc.c:97
Code: 42 80 3c 28 00 74 08 48 89 df e8 74 40 3d fc 4c 89 33 b0 01 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 da 4a db fb 90 <0f> 0b 90 eb e3 44 89 e1 80 e1 07 38 c1 0f 8c ff fe ff ff 4c 89 e7
RSP: 0018:ffffc900034569a8 EFLAGS: 00010283
RAX: ffffffff85e48576 RBX: ffffc90003456b20 RCX: 0000000000080000
RDX: ffffc9000cb4b000 RSI: 0000000000001618 RDI: 0000000000001619
RBP: 1ffff9200068ad64 R08: ffffffff8f7ed977 R09: 1ffffffff1efdb2e
R10: dffffc0000000000 R11: ffffffff85e48440 R12: 00000028016b7529
R13: dffffc0000000000 R14: ffff8881423f4028 R15: 00000028016b7529
FS:  0000000000000000(0000) GS:ffff8881260cb000(0063) knlGS:00000000f50a6b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00007f7688d79018 CR3: 00000000282d4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 drm_crtc_get_last_vbltimestamp drivers/gpu/drm/drm_vblank.c:878 [inline]
 drm_crtc_next_vblank_start+0x223/0x470 drivers/gpu/drm/drm_vblank.c:1012
 set_fence_deadline drivers/gpu/drm/drm_atomic_helper.c:1596 [inline]
 drm_atomic_helper_wait_for_fences+0x265/0x8c0 drivers/gpu/drm/drm_atomic_helper.c:1643
 commit_tail+0x79/0x3a0 drivers/gpu/drm/drm_atomic_helper.c:1857
 drm_atomic_helper_commit+0xa6b/0xb10 drivers/gpu/drm/drm_atomic_helper.c:2111
 drm_atomic_commit+0x25f/0x2c0 drivers/gpu/drm/drm_atomic.c:1518
 drm_client_modeset_commit_atomic+0x620/0x760 drivers/gpu/drm/drm_client_modeset.c:1079
 drm_client_modeset_commit_locked+0xcb/0x4d0 drivers/gpu/drm/drm_client_modeset.c:1182
 drm_client_modeset_commit+0x4a/0x70 drivers/gpu/drm/drm_client_modeset.c:1208
 __drm_fb_helper_restore_fbdev_mode_unlocked+0x9d/0x1b0 drivers/gpu/drm/drm_fb_helper.c:237
 drm_fb_helper_set_par+0xaf/0x100 drivers/gpu/drm/drm_fb_helper.c:1359
 fb_set_var+0x818/0xf60 drivers/video/fbdev/core/fbmem.c:312
 fbcon_switch+0x759/0x1fc0 drivers/video/fbdev/core/fbcon.c:2127
 redraw_screen+0x56a/0xe90 drivers/tty/vt/vt.c:957
 vc_do_resize+0x122d/0x1770 drivers/tty/vt/vt.c:1272
 vc_resize include/linux/vt_kern.h:49 [inline]
 fbcon_modechanged+0x70e/0x11b0 drivers/video/fbdev/core/fbcon.c:2680
 do_fb_ioctl+0x6fd/0x750 drivers/video/fbdev/core/fb_chrdev.c:92
 fb_compat_ioctl+0x2f4/0x780 drivers/video/fbdev/core/fb_chrdev.c:293
 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:947 [inline]
 __ia32_compat_sys_ioctl+0x551/0x840 fs/ioctl.c:947
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f86539
Code: 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 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f50a655c EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000000004601
RDX: 0000000080000380 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   4:	10 07                	adc    %al,(%rdi)
   6:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   a:	10 08                	adc    %cl,(%rax)
   c:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  20:	00 51 52             	add    %dl,0x52(%rcx)
  23:	55                   	push   %rbp
  24:	89 e5                	mov    %esp,%ebp
  26:	0f 34                	sysenter
  28:	cd 80                	int    $0x80
* 2a:	5d                   	pop    %rbp <-- trapping instruction
  2b:	5a                   	pop    %rdx
  2c:	59                   	pop    %rcx
  2d:	c3                   	ret
  2e:	90                   	nop
  2f:	90                   	nop
  30:	90                   	nop
  31:	90                   	nop
  32:	90                   	nop
  33:	90                   	nop
  34:	90                   	nop
  35:	90                   	nop
  36:	90                   	nop
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop