syzbot

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WARNING: CPU: 1 PID: 5844 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: 1 UID: 0 PID: 5844 Comm: syz-executor123 Not tainted 6.13.0-rc6-syzkaller-00036-gfbfd64d25c7a #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 18 33 09 fc 48 89 5d 00 b0 01 5b 41 5c 41 5d 41 5e 41 5f 5d e9 4e 8b f3 05 e8 5e ce 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:ffffc90002ec72e8 EFLAGS: 00010093
RAX: ffffffff85fcb5c2 RBX: 0000001161b7a015 RCX: ffff8880227c8000
RDX: 0000000000000000 RSI: 0000001161b7a015 RDI: 0000001161b7a015
RBP: ffffc90002ec73b0 R08: ffffffff85fcb52f R09: fffff520005d8e64
R10: dffffc0000000000 R11: ffffffff85fcb440 R12: 0000001161b7a015
R13: ffff888020b5d150 R14: 1ffff920005d8e76 R15: ffff888025510000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc47f357a8 CR3: 000000000e736000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 drm_crtc_get_last_vbltimestamp drivers/gpu/drm/drm_vblank.c:878 [inline]
 drm_get_last_vbltimestamp drivers/gpu/drm/drm_vblank.c:897 [inline]
 drm_update_vblank_count+0x25d/0x9c0 drivers/gpu/drm/drm_vblank.c:311
 drm_vblank_disable_and_save+0xef/0x3b0 drivers/gpu/drm/drm_vblank.c:480
 drm_crtc_vblank_off+0x34b/0x990 drivers/gpu/drm/drm_vblank.c:1363
 disable_outputs drivers/gpu/drm/drm_atomic_helper.c:1214 [inline]
 drm_atomic_helper_commit_modeset_disables+0xd01/0x1a10 drivers/gpu/drm/drm_atomic_helper.c:1418
 vkms_atomic_commit_tail+0x50/0x200 drivers/gpu/drm/vkms/vkms_drv.c:72
 commit_tail+0x2ab/0x3c0 drivers/gpu/drm/drm_atomic_helper.c:1833
 drm_atomic_helper_commit+0x953/0x9f0 drivers/gpu/drm/drm_atomic_helper.c:2073
 drm_atomic_commit+0x296/0x2f0 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
 drm_client_modeset_commit+0x4a/0x70 drivers/gpu/drm/drm_client_modeset.c:1199
 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:237 [inline]
 drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:264 [inline]
 drm_fb_helper_lastclose+0xbb/0x180 drivers/gpu/drm/drm_fb_helper.c:1975
 drm_fbdev_client_restore+0x34/0x40 drivers/gpu/drm/drm_fbdev_client.c:30
 drm_client_dev_restore+0x134/0x270 drivers/gpu/drm/drm_client_event.c:104
 drm_lastclose drivers/gpu/drm/drm_file.c:396 [inline]
 drm_release+0x335/0x410 drivers/gpu/drm/drm_file.c:429
 __fput+0x23e/0xa50 fs/file_table.c:450
 task_work_run+0x251/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2a/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 0033:0x7f19f35c60f9
Code: Unable to access opcode bytes at 0x7f19f35c60cf.
RSP: 002b:00007ffc47f35848 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f19f35c60f9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007f19f36413b0 R08: ffffffffffffffb8 R09: 00000000000000a0
R10: 00000000000000a0 R11: 0000000000000246 R12: 00007f19f36413b0
R13: 0000000000000000 R14: 00007f19f3641e20 R15: 00007f19f35942d0
 </TASK>