3) with CONFIG_NUMA set, there are undefined symbols building modules:

scripts/modpost vmlinux drivers/md/dm-mod.o drivers/net/e1000/e1000.o drivers/net/eepro100.o drivers/md/md.o drivers/net/mii.o fs/xfs/xfs.o
*** Warning: cpu_info__per_cpu [fs/xfs/xfs.ko] undefined!
*** Warning: cpu_info__per_cpu [drivers/md/md.ko] undefined!
*** Warning: cpu_to_node_map [drivers/md/md.ko] undefined!

exporting them in ia64_ksyms.c fixes the problem.