One more thing -- this whole cpu_xxxx_map->cpu_xxxx_mask issue only affects s390, s390x and ppc64, correct? The s390[x] architectures unconditionally require "cpu_online_map" to exist in their respective s390[x]_get_smp_cpus() functions. And ppc64 requires the existence of either cpu_present_map or cpu_online_map in its ppc64_paca_init() function. But the other architectures look like they get along without them. Dave