Newer Open MPI is using a new set of PMIx variables to query for HWLOC topology. It distinguished at HWLOC major versions as HWLOC v2.x XMLs is not backwards compatible.
Created attachment 13346 [details] Export HWLOC version-specific PMIx vars with topology Fix
Created attachment 13408 [details] [19.05 and upper] Export HWLOC version-specific PMIx vars with topology The same patch, but for Slurm versions 19.05 and upper.