Created attachment 141697 [details]
4.19 rc4 boot log (black screen)

AMDGPU fails to initialise the graphics card with mainline kernel 4.19, from
rc1 to rc4, resulting in a black screen on boot.

4.18.8 boots to the desktop without any fatal errors, and functions as
expected.
The regression happened some time before 4.19 rc1 but after the 4.18 release.

Graphics card is:
01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc.
[AMD/ATI] Bonaire XT [Radeon HD 7790/8770 / R7 360 / R9 260/360 OEM]
[1002:665c]

I attempted to bisect it, but I kept hitting another (possibly unrelated) bug
that would cause a panic on boot and thus was unable to.
Attached are the kernel logs from both 4.18.8 and 4.19 rc4.

Running the latest available firmware for this card from the git repo.