Because 256 causes overflows in some code that stores them in 8 bit fields and the x86 APIC architecture cannot handle more than 255 anyways. Signed-off-by: Andi Kleen <ak@xxxxxxx> --- arch/x86_64/Kconfig | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) Index: linux/arch/x86_64/Kconfig =================================================================== --- linux.orig/arch/x86_64/Kconfig +++ linux/arch/x86_64/Kconfig @@ -323,7 +323,7 @@ config HAVE_ARCH_EARLY_PFN_TO_NID config NR_CPUS int "Maximum number of CPUs (2-256)" - range 2 256 + range 2 255 depends on SMP default "8" help - : send the line "unsubscribe linux-x86_64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
