gistfile1.txt

[   20.427731] ------------[ cut here ]------------
[   20.437426] driver forgot to call drm_crtc_vblank_off()
[   20.447663] WARNING: CPU: 1 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:892 drm_atomic_helper_commit_modeset_disables+0x3b8/0x3e0
[   20.464858] Modules linked in: uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core sun8i_codec_analog lima videodev media sun8i_codec sun4i_i2s 
gpio_keys snd_soc_simple_card snd_soc_simple_card_utils
[   20.495611] CPU: 1 PID: 31 Comm: kworker/1:1 Not tainted 4.15.0-rc2-ARCH+ #49
[   20.508348] Hardware name: Pinebook (DT)
[   20.517858] Workqueue: events drm_mode_rmfb_work_fn
[   20.528350] task: 0000000099a238b8 task.stack: 0000000064e5cef2
[   20.540011] pstate: 00000005 (nzcv daif -PAN -UAO)
[   20.550569] pc : drm_atomic_helper_commit_modeset_disables+0x3b8/0x3e0
[   20.562919] lr : drm_atomic_helper_commit_modeset_disables+0x3b8/0x3e0
[   20.575144] sp : ffff00000a6fbc00
[   20.584120] x29: ffff00000a6fbc00 x28: ffff000008e14ec8 
[   20.595197] x27: ffff800077e2dc00 x26: 0000000000000030 
[   20.606183] x25: 0000000000000000 x24: ffff000009132728 
[   20.617084] x23: ffff0000090a89d8 x22: ffff8000780a0000 
[   20.627899] x21: ffff8000780a5028 x20: 0000000000000000 
[   20.638612] x19: ffff800077c6e380 x18: 0000000000000010 
[   20.649294] x17: 0000ffffa0499970 x16: ffff00000813c148 
[   20.659977] x15: 0000000000000001 x14: ffff000008db3180 
[   20.670497] x13: 0000000000000000 x12: 0000000000000000 
[   20.680841] x11: ffff000009399b40 x10: ffff00000873bf08 
[   20.691147] x9 : 0000000000000020 x8 : 0000000000000015 
[   20.701386] x7 : 0000000000000001 x6 : 0000000000001e65 
[   20.711581] x5 : 0000000000000000 x4 : 0000000000000000 
[   20.721605] x3 : 0000000000000000 x2 : ffff80007bf7b440 
[   20.731612] x1 : 0000800072bfa000 x0 : 000000000000002b 
[   20.741612] Call trace:
[   20.748698]  drm_atomic_helper_commit_modeset_disables+0x3b8/0x3e0
[   20.759511]  drm_atomic_helper_commit_tail+0x28/0x78
[   20.769058]  commit_tail+0x7c/0x80
[   20.777000]  drm_atomic_helper_commit+0xe0/0x160
[   20.786179]  drm_atomic_commit+0x5c/0x68
[   20.794601]  drm_framebuffer_remove+0x2d0/0x3f8
[   20.803667]  drm_mode_rmfb_work_fn+0x68/0x90
[   20.812492]  process_one_work+0x19c/0x3f0
[   20.821084]  worker_thread+0x54/0x440
[   20.829281]  kthread+0x134/0x138
[   20.836978]  ret_from_fork+0x10/0x1c
[   20.845026] ---[ end trace 58680511897c1280 ]---

Got the following from just released arch build for regular pine64 (which boots fine was has no hdmi output)
[ 618.664808] driver forgot to call drm_crtc_vblank_off()
[ 618.670169] WARNING: CPU: 0 PID: 357 at drivers/gpu/drm/drm_atomic_helper.c:892 drm_atomic_helper_commit_modeset_disables+0x3b8/0x3e0
[ 618.682147] Modules linked in: r8723bs(C) cfg80211 rfkill lima snd_soc_hdmi_codec dw_hdmi_i2s_audio sun4i_i2s sun8i_codec sun8i_codec_analog snd_soc_simple_card snd_soc_simple_card_utils