------------[ cut here ]------------ faux_driver vkms: [drm] vblank wait timed out on crtc 0 WARNING: drivers/gpu/drm/drm_vblank.c:1318 at drm_wait_one_vblank+0x39a/0x5c0 drivers/gpu/drm/drm_vblank.c:1318, CPU#1: kworker/1:2/828 Modules linked in: CPU: 1 UID: 0 PID: 828 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events drm_fb_helper_damage_work RIP: 0010:drm_wait_one_vblank+0x587/0x5c0 drivers/gpu/drm/drm_vblank.c:1318 Code: 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ef e8 ba cb f6 fc 4d 8b 7d 00 48 89 df 4c 89 e6 4c 89 fa 8b 4c 24 04 <67> 48 0f b9 3a e9 d5 fc ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 0f RSP: 0018:ffffc90004157860 EFLAGS: 00010246 RAX: 1ffff11028175400 RBX: ffffffff8ee5b070 RCX: 0000000000000000 RDX: ffffffff8b569b80 RSI: ffffffff8b584ca0 RDI: ffffffff8ee5b070 RBP: ffffc90004157948 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1db66ef R12: ffffffff8b584ca0 R13: ffff888140baa000 R14: 1ffff9200082af10 R15: ffffffff8b569b80 FS: 0000000000000000(0000) GS:ffff888126def000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fce674dbf98 CR3: 000000000d3a8000 CR4: 00000000003526f0 Call Trace: drm_client_modeset_wait_for_vblank+0xc5/0xf0 drivers/gpu/drm/drm_client_modeset.c:1330 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:334 [inline] drm_fb_helper_damage_work+0xc9/0x650 drivers/gpu/drm/drm_fb_helper.c:369 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 7: fc ff df a: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) e: 74 08 je 0x18 10: 4c 89 ef mov %r13,%rdi 13: e8 ba cb f6 fc call 0xfcf6cbd2 18: 4d 8b 7d 00 mov 0x0(%r13),%r15 1c: 48 89 df mov %rbx,%rdi 1f: 4c 89 e6 mov %r12,%rsi 22: 4c 89 fa mov %r15,%rdx 25: 8b 4c 24 04 mov 0x4(%rsp),%ecx * 29: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2e: e9 d5 fc ff ff jmp 0xfffffd08 33: 44 89 f9 mov %r15d,%ecx 36: 80 e1 07 and $0x7,%cl 39: 80 c1 03 add $0x3,%cl 3c: 38 c1 cmp %al,%cl 3e: 0f .byte 0xf