diff -Nru a/arch/ppc64/kernel/smp.c b/arch/ppc64/kernel/smp.c
--- a/arch/ppc64/kernel/smp.c	Tue Jul 27 13:44:45 2004
+++ b/arch/ppc64/kernel/smp.c	Tue Jul 27 13:44:45 2004
@@ -422,7 +422,11 @@
 	}
 
 	maxcpus = ireg[num_addr_cell + num_size_cell];
-	/* DRENG need to account for threads here too */
+
+	/* Double maxcpus for processors which have SMT capability */
+	if (cur_cpu_spec->cpu_features & CPU_FTR_SMT)
+		maxcpus *= 2;
+
 
 	if (maxcpus > NR_CPUS) {
 		printk(KERN_WARNING