------------[ cut here ]------------ faux_driver vkms: [drm] vblank wait timed out on crtc 0 WARNING: drivers/gpu/drm/drm_vblank.c:1320 at drm_crtc_wait_one_vblank+0x357/0x500 drivers/gpu/drm/drm_vblank.c:1320, CPU#1: kworker/1:1/44 Modules linked in: CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: events drm_fb_helper_damage_work RIP: 0010:drm_crtc_wait_one_vblank+0x4b6/0x500 drivers/gpu/drm/drm_vblank.c:1320 Code: e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ef e8 2a 7a c0 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 79 f6 ff ff b8 92 ff ff ff RSP: 0018:ffffc90000b47920 EFLAGS: 00010246 RAX: 1ffff11004cb4000 RBX: ffffffff903eabd0 RCX: 0000000000000000 RDX: ffffffff8c5262c0 RSI: ffffffff8c541e60 RDI: ffffffff903eabd0 RBP: ffffc90000b47a08 R08: ffffffff903342b7 R09: 1ffffffff2066856 R10: dffffc0000000000 R11: fffffbfff2066857 R12: ffffffff8c541e60 R13: ffff8880265a0000 R14: 0000000000000000 R15: ffffffff8c5262c0 FS: 0000000000000000(0000) GS:ffff888125115000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2245de8600 CR3: 0000000064ea0000 CR4: 00000000003526f0 DR0: 0000000000000008 DR1: 0000000000000007 DR2: 0000000000000004 DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000400 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:236 [inline] drm_fb_helper_damage_work+0x134/0x750 drivers/gpu/drm/drm_fb_helper.c:274 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 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 2a 7a c0 fc call 0xfcc07a44 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 79 f6 ff ff call 0xfffff6b4 3b: b8 92 ff ff ff mov $0xffffff92,%eax