------------[ cut here ]------------
WARNING: CPU: 0 PID: 7867 at drivers/gpu/drm/vkms/vkms_crtc.c:98 vkms_get_vblank_timestamp+0x183/0x1b0 drivers/gpu/drm/vkms/vkms_crtc.c:98
Modules linked in:
CPU: 0 UID: 0 PID: 7867 Comm: syz.8.432 Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:vkms_get_vblank_timestamp+0x183/0x1b0 drivers/gpu/drm/vkms/vkms_crtc.c:98
Code: 42 80 3c 30 00 74 08 48 89 ef e8 28 41 09 fc 48 89 5d 00 b0 01 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 1e d8 a2 fb 90 <0f> 0b 90 eb e4 89 d9 80 e1 07 38 c1 0f 8c cd fe ff ff 48 89 df e8
RSP: 0018:ffffc90002e474c8 EFLAGS: 00010283
RAX: ffffffff85fc9bc2 RBX: 000000234f873a64 RCX: 0000000000080000
RDX: ffffc90004821000 RSI: 000000000000094b RDI: 000000000000094c
RBP: ffffc90002e47660 R08: ffffffff85fc9b2f R09: 0000000000000000
R10: ffffc90003659000 R11: ffffffff85fc9a40 R12: 000000234f873a64
R13: ffff888143761150 R14: 1ffff920005c8ecc R15: ffff888024a9c000
FS:  00007f22407a26c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f22407a1f98 CR3: 000000002822a000 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+0x229/0x490 drivers/gpu/drm/drm_vblank.c:1012
 set_fence_deadline drivers/gpu/drm/drm_atomic_helper.c:1558 [inline]
 drm_atomic_helper_wait_for_fences+0x277/0x8e0 drivers/gpu/drm/drm_atomic_helper.c:1605
 drm_atomic_helper_commit+0x53a/0x9f0 drivers/gpu/drm/drm_atomic_helper.c:2034
 drm_atomic_commit+0x294/0x2f0 drivers/gpu/drm/drm_atomic.c:1518
 drm_client_modeset_commit_atomic+0x670/0x7d0 drivers/gpu/drm/drm_client_modeset.c:1070
 drm_client_modeset_commit_locked+0xe0/0x520 drivers/gpu/drm/drm_client_modeset.c:1173
 pan_display_atomic drivers/gpu/drm/drm_fb_helper.c:1377 [inline]
 drm_fb_helper_pan_display+0x379/0xc10 drivers/gpu/drm/drm_fb_helper.c:1437
 fb_pan_display+0x3a3/0x680 drivers/video/fbdev/core/fbmem.c:191
 bit_update_start+0x4d/0x1c0 drivers/video/fbdev/core/bitblit.c:381
 fbcon_modechanged+0xb7b/0x1200 drivers/video/fbdev/core/fbcon.c:2686
 do_fb_ioctl+0x71b/0x7b0 drivers/video/fbdev/core/fb_chrdev.c:92
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f223f985d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f22407a2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f223fb75fa0 RCX: 00007f223f985d29
RDX: 0000000020000100 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00007f223fa01b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f223fb75fa0 R15: 00007f223fc9fa28
 </TASK>