I have run into two bugs on PPC64 on 2.6.32 kernel.
BUG #1: No Socket information in lstopo output:
Machine (3654MB) + L2 #0 (4096KB)
L1 #0 (64KB) + Core #0
PU #0 (phys=0)
PU #1 (phys=1)
L1 #1 (64KB) + Core #1
PU #2 (phys=2)
PU #3 (phys=3)
Fixed in the latest version (tried hwloc-1.1a1r2301.tar.gz)
On some PPC64, kernel 2.6.32 I have crash when running
$ lstopo a.txt
Segmentation fault (core dumped)
$ gdb /usr/local/bin/lstopo core.8771
Program terminated with signal 11, Segmentation fault.
#0 0x00000000100060b4 in .merge ()
It appears only on some PPC64 boxes.
This issue is also gone with in the latest version (tried hwloc-1.1a1r2301.tar.gz)
I wonder if you are aware of these problems. let me know if you need more details.