Thanks for helping me on this. I got the card specifically to render in Blender and I don't wish to use Windows.
Steps to reproduce:
1. Install driver as specified here:
2. Run blender from terminal like this:
blender --debug-value 256
3. Change to Cycles mode
4. In the Render tab, scroll to bottom, expand Debug, Tick 'Split Kernel', under OpenCL flags for Kernel select 'Split', for Device select 'All'.
5. Open Blender User Preferences, System, Cycles compute device OpenCL - Vega 10 XT [Radeon RX Vega 64] Save User Settings.
Our verification team was unable to reproduce the issue. Please make sure that ROCm component required for running OpenCL applications is installed correctly [i.e. installing “rocm-amdgpu-pro” and setting “LLVM_BIN” path].
I reinstalled Ubuntu 17.04 and just installed Rocm from the instructiona on GitHub and the split kernel worked!
However, when I switched to viewport preview, it didn’t work and Blender crashed.
Should I try also installing the 17.30 stack within the rocm kernel?
You don't require that AMDGPU RPO component on ROCm driver itself. You can try ROCm OpenCL runtime from here: GitHub - RadeonOpenCompute/ROCm-OpenCL-Runtime: ROCm OpenOpenCL Runtime . If you see any issue, please report to the same GitHub page.
Btw, may I assume that Blender is working fine for other opencl kernels?
I'm afraid I don't know about other opencl kernels. The above method was the only way I could get the Blender User Preferences to see the card.