Comment 4 for bug 1111878

OK, so I pushed a branch that should resolve the key error problem. I was not able to actually recreate your failure, however, so I am really only taking a best guess based on the code and the error. So as asked above, could you please provide the contents of /proc/cpuinfo:

cat /proc/cpuinfo > cpuinfo.txt

and tell me more about the system you're running this on and encountering the error.