Troubleshooting Ubuntu 20 and a fresh install of Amd drivers

I've been quite late to this discussion and I want to address a few points:

• Regarding Windows 10 set-up being 'easier' than Ubuntu - I think this is largely due to the monopoly that Microsoft still holds in the desktop space. As a result the collective community all focus their efforts on Windows installations - other operating systems are an afterthought.
• I think AMD has just had to make do with limited resources compared with their competition in Intel and Nvidia. Given the aforementioned point about Windows being the dominant OS, it makes sense that they focus their efforts there. Anything else is secondary.
• While Nvidia on Linux 'works well', it only does so if you're willing to accept closed-source proprietary drivers. For a lot of end-users' perspective this is acceptable: thus the vast majority of what few Linux systems there are are running with Nvidia GPUs (and I assume under proprietary drivers for at least recent GPU generations because who would pay the Nvidia premium only for it to be crippled by the lack of mode-setting in the open-source drivers?) In contrast I feel AMD is a much better example in the open-source driver space, even if it's only due to economic reasons (by allowing the community to contribute they effectively increase their developer resources). Besides, with Nvidia already dominating with their CUDA ecosystem, AMD can't really afford to compete with a proprietary system unless it's already compelling enough to draw existing CUDA users away.
• Current AMD driver releases for Linux are only designed for Ubuntu kernel 5.4.x. If running a recent point release of Ubuntu 20.04, this may mean getting updated to kernel 5.8.x. Should just be a matter of removing the 'hwe' (hardware enablement kernel meta-packages) and reverting to the original 5.4.x kernel releases that 20.04 originally came with.
• With assistance from MountKidd a few weeks back, I determined that 20.40 drivers don't work beyond Ubuntu kernel 5.4.0-54. 20.45 drivers do, however, as already mentioned, they replaced PAL-based OpenCL with ROCr (while 'legacy' OpenCL remains available for GPU generations before Vega).

That last point is a sticking point for me. While I can run Fiji with amdgpu-pro 20.45 and legacy OpenCL, Vega with amdgpu-pro 20.45 and ROCr-based OpenCL breaks all GPU processing for me. Not just for Einstein but for any BOINC-related processing. So I'm staying with amdgpu-pro 20.40 (and PAL-based OpenCL) for the time being, which also means I'm stuck on an older kernel. I've reported this to the AMD community and I understand it's been recorded as an issue in the developers' internal system, but I haven't seen any update as yet. My hope is that the next driver release may allow both BOINC GPU processing again even if it's with ROCr-based OpenCL (which I have not had any success with at all to date, even installing separately from amdgpu-pro).

Is anyone actually successfully running BOINC GPU processing under 20.45 drivers with ROCr-based OpenCL?

Thanks for the feedback. That's very interesting that you are successful with Navi 10. I understand Ellesmere would be running on 'legacy' OpenCL, but Navi 10 would be running via ROCr. Have you noticed any significant change in run-times between PAL- and ROCr-based OpenCL? I wonder if you would still be running without apparent issue with only ROCr and Navi 10 installed.

BTW, kernel 5.8 was only introduced with Ubuntu 20.04.2, though you can always switch to kernel 5.4, as I have. I would advise against disabling updates even on Linux - there's a valid place for them.

For me, when I attempt to run ROCr-based OpenCL on Vega 20, I get immediate task errors a few seconds after starting. BOINC can recognise ROCr-based OpenCL, but generates this error for every Einstein GPU task:

Couldn't create OpenCL command queue (error: -6)!

I wonder if there's something odd where ROCr support for Navi 10 is working better than Vega 20.