------------[ cut here ]------------ WARNING: CPU: 0 PID: 9150 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: 9150 Comm: syz.0.837 Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:vkms_get_vblank_timestamp+0x167/0x1b0 drivers/gpu/drm/vkms/vkms_crtc.c:97 Code: c3 fb e8 ec 83 b1 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 ea b8 c3 fb 90 <0f> 0b 90 eb b5 e8 0f 33 29 fc e9 dc fe ff ff e8 95 33 29 fc e9 14 RSP: 0018:ffffc90004257030 EFLAGS: 00010246 RAX: 0000000000080000 RBX: ffff88814233c028 RCX: ffffc9000d052000 RDX: 0000000000080000 RSI: ffffffff85f769f6 RDI: 0000000000000006 RBP: 00000062f3f407ea R08: 0000000000000006 R09: 00000062f3f407ea R10: 00000062f3f407ea R11: 0000000000000000 R12: ffffc90004257198 R13: 00000062f3f407ea R14: 0000000000004e20 R15: ffffffff85f76890 FS: 00007faf167956c0(0000) GS:ffff8881249e1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000057f000 CR3: 000000007a8fc000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: drm_crtc_get_last_vbltimestamp+0x102/0x1b0 drivers/gpu/drm/drm_vblank.c:878 drm_crtc_next_vblank_start+0x182/0x300 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+0x203/0x830 drivers/gpu/drm/drm_atomic_helper.c:1643 commit_tail+0x83/0x400 drivers/gpu/drm/drm_atomic_helper.c:1857 drm_atomic_helper_commit+0x2fd/0x380 drivers/gpu/drm/drm_atomic_helper.c:2111 drm_atomic_commit+0x231/0x300 drivers/gpu/drm/drm_atomic.c:1518 drm_client_modeset_commit_atomic+0x69d/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1079 drm_client_modeset_commit_locked+0x14d/0x580 drivers/gpu/drm/drm_client_modeset.c:1182 drm_client_modeset_commit+0x4f/0x80 drivers/gpu/drm/drm_client_modeset.c:1208 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:237 [inline] __drm_fb_helper_restore_fbdev_mode_unlocked+0x19f/0x200 drivers/gpu/drm/drm_fb_helper.c:216 drm_fb_helper_set_par+0xd8/0x120 drivers/gpu/drm/drm_fb_helper.c:1359 fb_set_var+0x838/0x11f0 drivers/video/fbdev/core/fbmem.c:312 fbcon_switch+0x4dc/0x14c0 drivers/video/fbdev/core/fbcon.c:2127 redraw_screen+0x2be/0x760 drivers/tty/vt/vt.c:957 fbcon_modechanged+0x456/0x700 drivers/video/fbdev/core/fbcon.c:2691 fbcon_update_vcs+0x42/0x50 drivers/video/fbdev/core/fbcon.c:2736 do_fb_ioctl+0x787/0x7e0 drivers/video/fbdev/core/fb_chrdev.c:92 fb_ioctl+0xe5/0x150 drivers/video/fbdev/core/fb_chrdev.c:169 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faf1598e969 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:00007faf16795038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007faf15bb6080 RCX: 00007faf1598e969 RDX: 0000200000000040 RSI: 0000000000004601 RDI: 000000000000000c RBP: 00007faf15a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007faf15bb6080 R15: 00007ffe85ae74c8