diff --git a/arch/x86_64/kernel/mpparse.c b/arch/x86_64/kernel/mpparse.c
index 61a63be..ed6a558 100644
--- a/arch/x86_64/kernel/mpparse.c
+++ b/arch/x86_64/kernel/mpparse.c
@@ -23,6 +23,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/mc146818rtc.h>
 #include <linux/acpi.h>
+#include <linux/module.h>
 
 #include <asm/smp.h>
 #include <asm/mtrr.h>
@@ -45,7 +46,8 @@
 int apic_version [MAX_APICS];
 unsigned char mp_bus_id_to_type [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
 int mp_bus_id_to_pci_bus [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
-cpumask_t pci_bus_to_cpumask [256] = { [0 ... 255] = CPU_MASK_ALL };
+unsigned char pci_bus_to_node [256];
+EXPORT_SYMBOL(pci_bus_to_node);
 
 static int mp_current_pci_id = 0;
 /* I/O APIC entries */
diff --git a/arch/x86_64/pci/k8-bus.c b/arch/x86_64/pci/k8-bus.c
index 62349c7..7e7d0c2 100644
--- a/arch/x86_64/pci/k8-bus.c
+++ b/arch/x86_64/pci/k8-bus.c
@@ -53,25 +53,11 @@
 				for (j = SECONDARY_LDT_BUS_NUMBER(ldtbus);
 				     j <= SUBORDINATE_LDT_BUS_NUMBER(ldtbus);
 				     j++)
-					pci_bus_to_cpumask[j] =
-						node_to_cpumask(NODE_ID(nid));
+					pci_bus_to_node[j] = NODE_ID(nid);
 			}
 		}
 	}
 
-	/* quick sanity check */
-	printed = 0;
-	for (i = 0; i < 256; i++) {
-		if (cpus_empty(pci_bus_to_cpumask[i])) {
-			pci_bus_to_cpumask[i] = CPU_MASK_ALL;
-			if (printed)
-				continue;
-			printk(KERN_ERR
-			       "k8-bus.c: some busses have empty cpu mask\n");
-			printed = 1;
-		}
-	}
-
 	return 0;
 }
 
diff --git a/include/asm-generic/topology.h b/include/asm-generic/topology.h
index ec96e8b..5d9d70c 100644
--- a/include/asm-generic/topology.h
+++ b/include/asm-generic/topology.h
@@ -41,8 +41,15 @@
 #ifndef node_to_first_cpu
 #define node_to_first_cpu(node)	(0)
 #endif
+#ifndef pcibus_to_node
+#define pcibus_to_node(node)	(-1)
+#endif
+
 #ifndef pcibus_to_cpumask
-#define pcibus_to_cpumask(bus)	(cpu_online_map)
+#define pcibus_to_cpumask(bus)	(pcibus_to_node(bus) == -1 ? \
+					CPU_MASK_ALL : \
+					node_to_cpumask(pcibus_to_node(bus)) \
+				)
 #endif
 
 #endif /* _ASM_GENERIC_TOPOLOGY_H */
diff --git a/include/asm-i386/topology.h b/include/asm-i386/topology.h
index 98f9e68..6d0f675 100644
--- a/include/asm-i386/topology.h
+++ b/include/asm-i386/topology.h
@@ -60,12 +60,8 @@
 	return first_cpu(mask);
 }
 
-/* Returns the number of the node containing PCI bus number 'busnr' */
-static inline cpumask_t __pcibus_to_cpumask(int busnr)
-{
-	return node_to_cpumask(mp_bus_id_to_node[busnr]);
-}
-#define pcibus_to_cpumask(bus)	__pcibus_to_cpumask(bus->number)
+#define pcibus_to_node(bus) mp_bus_id_to_node[(bus)->number]
+#define pcibus_to_cpumask(bus) node_to_cpumask(pcibus_to_node(bus))
 
 /* sched_domains SD_NODE_INIT for NUMAQ machines */
 #define SD_NODE_INIT (struct sched_domain) {		\
diff --git a/include/asm-x86_64/topology.h b/include/asm-x86_64/topology.h
index da21573..8f77e9f 100644
--- a/include/asm-x86_64/topology.h
+++ b/include/asm-x86_64/topology.h
@@ -13,8 +13,8 @@
 extern cpumask_t cpu_online_map;
 
 extern unsigned char cpu_to_node[];
+extern unsigned char pci_bus_to_node[];
 extern cpumask_t     node_to_cpumask[];
-extern cpumask_t pci_bus_to_cpumask[];
 
 #ifdef CONFIG_ACPI_NUMA
 extern int __node_distance(int, int);
@@ -26,16 +26,8 @@
 #define parent_node(node)		(node)
 #define node_to_first_cpu(node) 	(__ffs(node_to_cpumask[node]))
 #define node_to_cpumask(node)		(node_to_cpumask[node])
-
-static inline cpumask_t __pcibus_to_cpumask(int bus)
-{
-	cpumask_t busmask = pci_bus_to_cpumask[bus];
-	cpumask_t online = cpu_online_map;
-	cpumask_t res;
-	cpus_and(res, busmask, online);
-	return res;
-}
-#define pcibus_to_cpumask(bus) __pcibus_to_cpumask(bus->number)
+#define pcibus_to_node(bus)		pci_bus_to_node[(bus)->number]
+#define pcibus_to_cpumask(bus)		node_to_cpumask(pcibus_to_node(bus));
 
 /* sched_domains SD_NODE_INIT for x86_64 machines */
 #define SD_NODE_INIT (struct sched_domain) {		\