[CRTC:35:crtc-0] vblank wait timed out WARNING: drivers/gpu/drm/drm_atomic_helper.c:1920 at drm_atomic_helper_wait_for_vblanks.part.0+0x738/0x8a0 drivers/gpu/drm/drm_atomic_helper.c:1920, CPU#3: kworker/3:4/6441 Modules linked in: CPU: 3 UID: 0 PID: 6441 Comm: kworker/3:4 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 04/01/2014 Workqueue: events drm_fb_helper_damage_work RIP: 0010:drm_atomic_helper_wait_for_vblanks.part.0+0x73e/0x8a0 drivers/gpu/drm/drm_atomic_helper.c:1920 Code: 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 04 01 84 c0 74 08 3c 03 0f 8e 44 01 00 00 48 8d 3d 58 0b 32 0b 8b b3 d8 00 00 00 <67> 48 0f b9 3a e9 e1 fc ff ff e8 93 df 75 fc e9 7c fe ff ff e8 19 RSP: 0000:ffffc90004e3f688 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888044019318 RCX: 1ffff1100880327e RDX: ffff8880250e7480 RSI: 0000000000000023 RDI: ffffffff90c27630 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff888023fbe500 FS: 0000000000000000(0000) GS:ffff8880976e3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000008001d000 CR3: 000000005b351000 CR4: 0000000000352ef0 Call Trace: drm_atomic_helper_wait_for_vblanks drivers/gpu/drm/drm_atomic_helper.c:1894 [inline] drm_atomic_helper_commit_tail+0xff/0x130 drivers/gpu/drm/drm_atomic_helper.c:1996 commit_tail+0x338/0x430 drivers/gpu/drm/drm_atomic_helper.c:2073 drm_atomic_helper_commit+0x303/0x380 drivers/gpu/drm/drm_atomic_helper.c:2311 drm_atomic_commit+0x230/0x300 drivers/gpu/drm/drm_atomic.c:1743 drm_atomic_helper_dirtyfb+0x603/0x790 drivers/gpu/drm/drm_damage_helper.c:183 drm_fbdev_shmem_helper_fb_dirty+0x1cc/0x310 drivers/gpu/drm/drm_fbdev_shmem.c:117 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:346 [inline] drm_fb_helper_damage_work+0x348/0x640 drivers/gpu/drm/drm_fb_helper.c:372 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 fc add %bh,%ah 4: ff lcall (bad) 5: df 48 89 fisttps -0x77(%rax) 8: f9 stc 9: 48 c1 e9 03 shr $0x3,%rcx d: 0f b6 04 01 movzbl (%rcx,%rax,1),%eax 11: 84 c0 test %al,%al 13: 74 08 je 0x1d 15: 3c 03 cmp $0x3,%al 17: 0f 8e 44 01 00 00 jle 0x161 1d: 48 8d 3d 58 0b 32 0b lea 0xb320b58(%rip),%rdi # 0xb320b7c 24: 8b b3 d8 00 00 00 mov 0xd8(%rbx),%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: e9 e1 fc ff ff jmp 0xfffffd15 34: e8 93 df 75 fc call 0xfc75dfcc 39: e9 7c fe ff ff jmp 0xfffffeba 3e: e8 .byte 0xe8 3f: 19 .byte 0x19