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WARNING: CPU: 1 PID: 5832 at drivers/gpu/drm/vkms/vkms_crtc.c:98 vkms_get_vblank_timestamp+0x185/0x1e0 drivers/gpu/drm/vkms/vkms_crtc.c:98
Modules linked in:
CPU: 1 UID: 0 PID: 5832 Comm: syz-executor166 Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:vkms_get_vblank_timestamp+0x185/0x1e0 drivers/gpu/drm/vkms/vkms_crtc.c:98
Code: d3 fb e8 de 43 c1 fb 48 89 e9 48 ba 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 11 00 75 50 48 89 45 00 eb c0 e8 8c 7c d3 fb 90 <0f> 0b 90 eb b5 e8 a1 94 36 fc e9 dc fe ff ff 48 89 df e8 24 95 36
RSP: 0018:ffffc90003cb7588 EFLAGS: 00010093
RAX: 0000000000000000 RBX: 0000000c999ba7e2 RCX: ffffffff85e6736c
RDX: ffff88802b392440 RSI: ffffffff85e673e4 RDI: 0000000000000006
RBP: ffffc90003cb76b0 R08: 0000000000000006 R09: 0000000c999ba7e2
R10: 0000000c999ba7e2 R11: 0000000000000004 R12: 0000000c999ba7e2
R13: ffff8880256d4000 R14: 0000000000004e20 R15: ffffffff85e67260
FS:  000055557944c380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7dabba04a0 CR3: 00000000789ba000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 drm_crtc_get_last_vbltimestamp+0x103/0x1b0 drivers/gpu/drm/drm_vblank.c:878
 drm_get_last_vbltimestamp drivers/gpu/drm/drm_vblank.c:897 [inline]
 drm_update_vblank_count+0x1b2/0x9d0 drivers/gpu/drm/drm_vblank.c:311
 drm_crtc_accurate_vblank_count+0xc2/0x260 drivers/gpu/drm/drm_vblank.c:424
 drm_crtc_arm_vblank_event+0xfb/0x2b0 drivers/gpu/drm/drm_vblank.c:1107
 vkms_crtc_atomic_flush+0x10b/0x2b0 drivers/gpu/drm/vkms/vkms_crtc.c:253
 drm_atomic_helper_commit_planes+0x61c/0x1000 drivers/gpu/drm/drm_atomic_helper.c:2820
 vkms_atomic_commit_tail+0x5e/0x240 drivers/gpu/drm/vkms/vkms_drv.c:73
 commit_tail+0x284/0x400 drivers/gpu/drm/drm_atomic_helper.c:1833
 drm_atomic_helper_commit+0x2fd/0x380 drivers/gpu/drm/drm_atomic_helper.c:2073
 drm_atomic_commit+0x232/0x300 drivers/gpu/drm/drm_atomic.c:1518
 drm_atomic_helper_set_config+0x14a/0x1a0 drivers/gpu/drm/drm_atomic_helper.c:3273
 drm_mode_setcrtc+0xdfc/0x1db0 drivers/gpu/drm/drm_crtc.c:869
 drm_ioctl_kernel+0x1e6/0x3d0 drivers/gpu/drm/drm_ioctl.c:796
 drm_ioctl+0x5d6/0xc00 drivers/gpu/drm/drm_ioctl.c:893
 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/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7dabb78ca9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffef02884a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000200000000380 RCX: 00007f7dabb78ca9
RDX: 0000200000000300 RSI: 00000000c06864a2 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000000000a0 R09: 00000000000000a0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>