I cannot find the code branch from “src/topology-x86.c “which can support for 32-bit APIC ID and CPUID leaf 0xb of Intel’s new processors.
So I think current hwLoc cannot support for latest Intel CPU with x2APIC.
Linux kernel 2.6.30 or following version already supports this hardware feature
and uses CPUID leaf 0xb to recognize the topology for more than 1024 logical processors in SGI’s super computer.
I think hwloc could also support this.
The following docs from Intel give details about x2APIC:
or <<Intel® 64 Architecture Processor Topology Enumeration>>