------------[ cut here ]------------
WARNING: CPU: 0 PID: 16733 at drivers/gpu/drm/vkms/vkms_crtc.c:97 vkms_get_vblank_timestamp+0x167/0x1b0 drivers/gpu/drm/vkms/vkms_crtc.c:97
Modules linked in:
CPU: 0 UID: 0 PID: 16733 Comm: syz.5.2923 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:vkms_get_vblank_timestamp+0x167/0x1b0 drivers/gpu/drm/vkms/vkms_crtc.c:97
Code: ac fb e8 5c 7c 99 fb 4c 89 e1 48 ba 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 11 00 75 43 49 89 04 24 eb c0 e8 3a 1c ac fb 90 <0f> 0b 90 eb b5 e8 cf 83 12 fc e9 dc fe ff ff e8 55 84 12 fc e9 14
RSP: 0018:ffffc9000cf174b8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888146eec028 RCX: ffffffff860f820e
RDX: ffff888058a10000 RSI: ffffffff860f8286 RDI: 0000000000000006
RBP: 000000c94802b8c0 R08: 0000000000000006 R09: 000000c94802b8c0
R10: 000000c94802b8c0 R11: 0000000000000000 R12: ffffc9000cf17620
R13: 000000c94802b8c0 R14: 0000000000004e20 R15: ffffffff860f8120
FS:  0000000000000000(0000) GS:ffff8881246b2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000002fc030 CR3: 0000000064cf0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 drm_crtc_get_last_vbltimestamp+0x105/0x1b0 drivers/gpu/drm/drm_vblank.c:879
 drm_crtc_next_vblank_start+0x182/0x300 drivers/gpu/drm/drm_vblank.c:1013
 set_fence_deadline drivers/gpu/drm/drm_atomic_helper.c:1711 [inline]
 drm_atomic_helper_wait_for_fences+0x203/0x830 drivers/gpu/drm/drm_atomic_helper.c:1758
 drm_atomic_helper_commit+0x1cf/0x380 drivers/gpu/drm/drm_atomic_helper.c:2187
 drm_atomic_commit+0x234/0x300 drivers/gpu/drm/drm_atomic.c:1577
 drm_client_modeset_commit_atomic+0x69d/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1103
 drm_client_modeset_commit_locked+0x14d/0x580 drivers/gpu/drm/drm_client_modeset.c:1206
 drm_client_modeset_commit+0x4f/0x80 drivers/gpu/drm/drm_client_modeset.c:1232
 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:238 [inline]
 __drm_fb_helper_restore_fbdev_mode_unlocked+0x19f/0x200 drivers/gpu/drm/drm_fb_helper.c:217
 drm_fbdev_client_restore+0x2c/0x40 drivers/gpu/drm/clients/drm_fbdev_client.c:31
 drm_client_dev_restore+0x1f6/0x2a0 drivers/gpu/drm/drm_client_event.c:117
 drm_lastclose drivers/gpu/drm/drm_file.c:408 [inline]
 drm_release+0x2c4/0x360 drivers/gpu/drm/drm_file.c:441
 __fput+0x402/0xb70 fs/file_table.c:468
 task_work_run+0x150/0x240 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x86f/0x2bf0 kernel/exit.c:961
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:40
 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_syscall_64+0x41c/0x4e0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f4a18eec9
Code: Unable to access opcode bytes at 0x7f9f4a18ee9f.
RSP: 002b:00007f9f4af5d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f9f4a3e6098 RCX: 00007f9f4a18eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f9f4a3e6098
RBP: 00007f9f4a3e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9f4a3e6128 R14: 00007fff962710b0 R15: 00007fff96271198
 </TASK>