[Bug 111122] 2500U: Graphics corruption on kernel 5.2

https://bugs.freedesktop.org/show_bug.cgi?id=111122

--- Comment #30 from William Bonnaventure william.bonnaventure@gmail.com --- Fixed issue with a BIOS update on Lenovo E485 (v1.54 with AMD 2500U) with Fedora 30 KDE.

I had an issue on previous BIOS that requires a kernel option to boot on all kernels (ivrs_ioapic[32]=00:14.0). After BIOS update, this option is not needed and there is no longer graphic corruption on Kernel 5.2+. This corruption was impacting at least Firefox, dolphin and the Plasma Desktop.

KDE plasma 5.15.5 mesa 19.1.6 xorg-x11-drv-amdgpu 19.0.1 libdrm 2.4.99

As of my observation, the graphic corruption was introduced in the amdgpu driver inside Kernel 5.2 and occurs only when forcing boot with the ivrs_ioapic override.