------------[ cut here ]------------ WARNING: CPU: 0 PID: 6533 at drivers/gpu/drm/vkms/vkms_crtc.c:103 vkms_get_vblank_timestamp+0x1cf/0x240 drivers/gpu/drm/vkms/vkms_crtc.c:103 Modules linked in: CPU: 0 PID: 6533 Comm: syz-executor.1 Not tainted 6.4.0-rc2-syzkaller-00238-gcbd6ac3837cd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 RIP: 0010:vkms_get_vblank_timestamp+0x1cf/0x240 drivers/gpu/drm/vkms/vkms_crtc.c:103 Code: b3 70 fc e8 23 bd 60 fc 4c 89 e1 48 ba 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 11 00 75 65 49 89 04 24 eb c4 e8 01 b3 70 fc <0f> 0b eb bb e8 a8 7c c3 fc e9 de fe ff ff e8 de 7c c3 fc e9 78 fe RSP: 0018:ffffc900091e7550 EFLAGS: 00010212 RAX: 0000000000006b4b RBX: 0000003174e7f32c RCX: ffffc90004505000 RDX: 0000000000040000 RSI: ffffffff85138fcf RDI: 0000000000000006 RBP: ffff88801ec4c000 R08: 0000000000000006 R09: 0000003174e7f32c R10: 0000003174e7f32c R11: 0000000000000000 R12: ffffc900091e76b8 R13: 0000003174e7f32c R14: 0000000000004e20 R15: ffffffff85138e00 FS: 0000000000000000(0000) GS:ffff8880b9800000(0063) knlGS:00000000f7efcb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000200d9000 CR3: 000000001931e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: drm_crtc_get_last_vbltimestamp+0x102/0x1a0 drivers/gpu/drm/drm_vblank.c:877 drm_crtc_next_vblank_start+0x186/0x300 drivers/gpu/drm/drm_vblank.c:1012 set_fence_deadline drivers/gpu/drm/drm_atomic_helper.c:1537 [inline] drm_atomic_helper_wait_for_fences+0x1f3/0x840 drivers/gpu/drm/drm_atomic_helper.c:1584 drm_atomic_helper_commit drivers/gpu/drm/drm_atomic_helper.c:2013 [inline] drm_atomic_helper_commit+0x1bd/0x370 drivers/gpu/drm/drm_atomic_helper.c:1985 drm_atomic_commit+0x20a/0x300 drivers/gpu/drm/drm_atomic.c:1503 drm_client_modeset_commit_atomic+0x69b/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1045 drm_client_modeset_commit_locked+0x149/0x580 drivers/gpu/drm/drm_client_modeset.c:1148 pan_display_atomic drivers/gpu/drm/drm_fb_helper.c:1726 [inline] drm_fb_helper_pan_display+0x28f/0x970 drivers/gpu/drm/drm_fb_helper.c:1786 fb_pan_display+0x2fb/0x6c0 drivers/video/fbdev/core/fbmem.c:924 bit_update_start+0x49/0x1f0 drivers/video/fbdev/core/bitblit.c:387 fbcon_modechanged+0x508/0x620 drivers/video/fbdev/core/fbcon.c:2700 fbcon_update_vcs+0x3e/0x50 drivers/video/fbdev/core/fbcon.c:2749 do_fb_ioctl+0x6e2/0x750 drivers/video/fbdev/core/fbmem.c:1127 fb_compat_ioctl+0x5b4/0x670 drivers/video/fbdev/core/fbmem.c:1328 __do_compat_sys_ioctl+0x255/0x2b0 fs/ioctl.c:968 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f43579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7efc5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 0000000000004601 RDX: 0000000020000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 retq 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi