------------[ cut here ]------------
WARNING: CPU: 1 PID: 16843 at drivers/gpu/drm/vkms/vkms_crtc.c:103 vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
Modules linked in:
CPU: 1 PID: 16843 Comm: syz-executor.4 Tainted: G    B              6.8.0-rc5-syzkaller-g9abbc24128bc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
lr : vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
sp : ffff8000a3e97090
x29: ffff8000a3e97090 x28: ffff0000c8f42880 x27: 0000000000000000
x26: 1ffff000147d2e20 x25: 1ffff000147d2e44 x24: 0000000000000000
x23: ffff0000c90b8000 x22: dfff800000000000 x21: 0000011715bae5a0
x20: 0000011715bae5a0 x19: ffff8000a3e97220 x18: 0000000000000000
x17: 0000000000000000 x16: ffff80008ac976c0 x15: 0000000000000002
x14: 1fffe0001987f1a1 x13: 0000000000000000 x12: ffff800099e5a000
x11: 0000000000040000 x10: 0000000000001022 x9 : ffff800097be9000
x8 : 0000000000001023 x7 : 0000000000000000 x6 : ffff800099e5a000
x5 : ffff0000cc3f8d18 x4 : ffff0000cc3f8cd8 x3 : 0000000000000000
x2 : ffff8000a3e97220 x1 : 0000011715bae5a0 x0 : 0000011715bae5a0
Call trace:
 vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
 drm_crtc_get_last_vbltimestamp drivers/gpu/drm/drm_vblank.c:867 [inline]
 drm_crtc_next_vblank_start+0x1d4/0x3e0 drivers/gpu/drm/drm_vblank.c:1002
 set_fence_deadline drivers/gpu/drm/drm_atomic_helper.c:1557 [inline]
 drm_atomic_helper_wait_for_fences+0x200/0x7c4 drivers/gpu/drm/drm_atomic_helper.c:1604
 drm_atomic_helper_commit+0x4d0/0x8d4 drivers/gpu/drm/drm_atomic_helper.c:2033
 drm_atomic_commit+0x24c/0x2a0 drivers/gpu/drm/drm_atomic.c:1514
 drm_client_modeset_commit_atomic+0x5a4/0x730 drivers/gpu/drm/drm_client_modeset.c:1051
 drm_client_modeset_commit_locked+0xd0/0x4a8 drivers/gpu/drm/drm_client_modeset.c:1154
 drm_client_modeset_commit+0x50/0x7c drivers/gpu/drm/drm_client_modeset.c:1180
 __drm_fb_helper_restore_fbdev_mode_unlocked+0xd4/0x178 drivers/gpu/drm/drm_fb_helper.c:251
 drm_fb_helper_set_par+0xc4/0x110 drivers/gpu/drm/drm_fb_helper.c:1344
 fb_set_var+0x6b8/0xce4 drivers/video/fbdev/core/fbmem.c:312
 do_fb_ioctl+0x748/0xd24 drivers/video/fbdev/core/fb_chrdev.c:90
 fb_ioctl+0xec/0x134 drivers/video/fbdev/core/fb_chrdev.c:169
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
irq event stamp: 0
hardirqs last  enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<ffff8000801b57f4>] copy_process+0x1318/0x3478 kernel/fork.c:2441
softirqs last  enabled at (0): [<ffff8000801b581c>] copy_process+0x1340/0x3478 kernel/fork.c:2442
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace 0000000000000000 ]---