Bug#1022806: linux-image-5.10.0-19-amd64: amggpu unbootable problem persists

[Felix Miata <mrmazda@earthlink.net>]

Oland [Radeon HD 8570 / R5 430 OEM R7 240/340 Radeon 520 OEM]
    vendor: Dell driver: radeon v: kernel arch: GCN-1 pcie: speed: 2.5 GT/s
    lanes: 8 ports: active: DP-1,DVI-I-1 empty: none bus-ID: 01:00.0
    chip-ID: 1002:6611

Same failure as in my previous comment #45 about GCN2. In Bullseye in both PCs,
workaround is to omit 'plymouth.enable=0 radeon.si_support=1' from linu line in
Grub, which absent installation of radeon DDX, forces use of modesetting DIX
instead of amdgpu DDX, which was working just fine until
linux-image-5.10.0-19-amd64 was installed. The resulting change in display output
names requires the xrandr script locating all the displays to be rewritten. On
this one I've not as yet attempted installation of backport kernel.
-- 
Evolution as taught in public schools is, like religion,
	based on faith, not based on science.

 Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!

Felix Miata