------------[ cut here ]------------ faux_driver vkms: [drm] vblank wait timed out on crtc 0 WARNING: drivers/gpu/drm/drm_vblank.c:1329 at drm_crtc_wait_one_vblank+0x3d5/0x590 drivers/gpu/drm/drm_vblank.c:1329, CPU#1: kworker/1:4/5626 Modules linked in: CPU: 1 UID: 0 PID: 5626 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events drm_fb_helper_damage_work RIP: 0010:drm_crtc_wait_one_vblank+0x53c/0x590 drivers/gpu/drm/drm_vblank.c:1329 Code: e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ef e8 94 fd c8 fc 4d 8b 7d 00 48 89 df 4c 89 e6 4c 89 fa 44 89 f1 <67> 48 0f b9 3a 48 8b 3c 24 44 89 f6 e8 13 f4 ff ff b8 92 ff ff ff RSP: 0018:ffffc90004a37920 EFLAGS: 00010246 RAX: 1ffff11004b6ca00 RBX: ffffffff8f96f7d0 RCX: 0000000000000000 RDX: ffffffff8bc18d60 RSI: ffffffff8bc35ae0 RDI: ffffffff8f96f7d0 RBP: ffffc90004a37a08 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1f1751f R12: ffffffff8bc35ae0 R13: ffff888025b65000 R14: 0000000000000000 R15: ffffffff8bc18d60 FS: 0000000000000000(0000) GS:ffff888125ff4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe4d452e000 CR3: 0000000042480000 CR4: 00000000003526f0 Call Trace: drm_client_modeset_wait_for_vblank+0xc5/0xf0 drivers/gpu/drm/drm_client_modeset.c:1331 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:237 [inline] drm_fb_helper_damage_work+0x131/0x720 drivers/gpu/drm/drm_fb_helper.c:275 process_one_work+0x98b/0x1630 kernel/workqueue.c:3318 process_scheduled_works kernel/workqueue.c:3401 [inline] worker_thread+0xb49/0x1140 kernel/workqueue.c:3482 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: e8 03 48 b9 00 call 0xb94808 5: 00 00 add %al,(%rax) 7: 00 00 add %al,(%rax) 9: fc cld a: ff lcall (bad) b: df 80 3c 08 00 74 filds 0x7400083c(%rax) 11: 08 4c 89 ef or %cl,-0x11(%rcx,%rcx,4) 15: e8 94 fd c8 fc call 0xfcc8fdae 1a: 4d 8b 7d 00 mov 0x0(%r13),%r15 1e: 48 89 df mov %rbx,%rdi 21: 4c 89 e6 mov %r12,%rsi 24: 4c 89 fa mov %r15,%rdx 27: 44 89 f1 mov %r14d,%ecx * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 48 8b 3c 24 mov (%rsp),%rdi 33: 44 89 f6 mov %r14d,%esi 36: e8 13 f4 ff ff call 0xfffff44e 3b: b8 92 ff ff ff mov $0xffffff92,%eax