------------[ 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+0x2e8/0x5a0 drivers/gpu/drm/drm_vblank.c:1318, CPU#2: kworker/2:2/1462 Modules linked in: CPU: 2 UID: 0 PID: 1462 Comm: kworker/2:2 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: events drm_fb_helper_damage_work RIP: 0010:drm_wait_one_vblank+0x2ee/0x5a0 drivers/gpu/drm/drm_vblank.c:1318 Code: 4c 8b 6d 50 4d 85 ed 0f 84 01 02 00 00 e8 aa fe 6b fc 48 89 ef e8 b2 20 92 00 48 89 c6 48 8d 3d e8 c9 40 0b 44 89 e1 4c 89 ea <67> 48 0f b9 3a e9 55 fe ff ff e8 83 fe 6b fc 48 89 ef e8 0b fd 25 RSP: 0018:ffffc9000c15fa10 EFLAGS: 00010293 RAX: ffffffff8c221840 RBX: ffff8880441c8000 RCX: 0000000000000000 RDX: ffffffff8c201220 RSI: ffffffff8c221840 RDI: ffffffff909326b0 RBP: ffff888025c96000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: ffff888023ac54b0 R12: 0000000000000000 R13: ffffffff8c201220 R14: 1ffff9200182bf45 R15: 0000000000008c97 FS: 0000000000000000(0000) GS:ffff8880978fa000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000003021bffc CR3: 0000000050a9a000 CR4: 0000000000352ef0 DR0: 000000006000003f DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: drm_client_modeset_wait_for_vblank+0xef/0x120 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+0x167/0x650 drivers/gpu/drm/drm_fb_helper.c:372 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 ---------------- Code disassembly (best guess): 0: 4c 8b 6d 50 mov 0x50(%rbp),%r13 4: 4d 85 ed test %r13,%r13 7: 0f 84 01 02 00 00 je 0x20e d: e8 aa fe 6b fc call 0xfc6bfebc 12: 48 89 ef mov %rbp,%rdi 15: e8 b2 20 92 00 call 0x9220cc 1a: 48 89 c6 mov %rax,%rsi 1d: 48 8d 3d e8 c9 40 0b lea 0xb40c9e8(%rip),%rdi # 0xb40ca0c 24: 44 89 e1 mov %r12d,%ecx 27: 4c 89 ea mov %r13,%rdx * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: e9 55 fe ff ff jmp 0xfffffe89 34: e8 83 fe 6b fc call 0xfc6bfebc 39: 48 89 ef mov %rbp,%rdi 3c: e8 .byte 0xe8 3d: 0b fd or %ebp,%edi 3f: 25 .byte 0x25