diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 23faaa890ffc..429c7014febc 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -293,7 +293,7 @@ static acpi_status __init find_mboard_resource(acpi_handle handle, u32 lvl,
 	return AE_OK;
 }
 
-static int __init is_acpi_reserved(unsigned long start, unsigned long end)
+static int __init is_acpi_reserved(u64 start, u64 end, unsigned not_used)
 {
 	struct resource mcfg_res;
 
@@ -310,6 +310,41 @@ static int __init is_acpi_reserved(unsigned long start, unsigned long end)
 	return mcfg_res.flags;
 }
 
+typedef int (*check_reserved_t)(u64 start, u64 end, unsigned type);
+
+static int __init is_mmconf_reserved(check_reserved_t is_reserved,
+		u64 addr, u64 size, int i,
+		typeof(pci_mmcfg_config[0]) *cfg, int with_e820)
+{
+	u64 old_size = size;
+	int valid = 0;
+
+	while (!is_reserved(addr, addr + size - 1, E820_RESERVED)) {
+		size >>= 1;
+		if (size < (16UL<<20))
+			break;
+	}
+
+	if (size >= (16UL<<20) || size == old_size) {
+		printk(KERN_NOTICE
+		       "PCI: MCFG area at %Lx reserved in %s\n",
+			addr, with_e820?"E820":"ACPI motherboard resources");
+		valid = 1;
+
+		if (old_size != size) {
+			/* update end_bus_number */
+			cfg->end_bus_number = cfg->start_bus_number + ((size>>20) - 1);
+			printk(KERN_NOTICE "PCI: updated MCFG configuration %d: base %lx "
+			       "segment %hu buses %u - %u\n",
+			       i, (unsigned long)cfg->address, cfg->pci_segment,
+			       (unsigned int)cfg->start_bus_number,
+			       (unsigned int)cfg->end_bus_number);
+		}
+	}
+
+	return valid;
+}
+
 static void __init pci_mmcfg_reject_broken(int early)
 {
 	typeof(pci_mmcfg_config[0]) *cfg;
@@ -324,21 +359,22 @@ static void __init pci_mmcfg_reject_broken(int early)
 
 	for (i = 0; i < pci_mmcfg_config_num; i++) {
 		int valid = 0;
-		u32 size = (cfg->end_bus_number + 1) << 20;
+		u64 addr, size;
+
 		cfg = &pci_mmcfg_config[i];
+		addr = cfg->start_bus_number;
+		addr <<= 20;
+		addr += cfg->address;
+		size = cfg->end_bus_number + 1 - cfg->start_bus_number;
+		size <<= 20;
 		printk(KERN_NOTICE "PCI: MCFG configuration %d: base %lx "
 		       "segment %hu buses %u - %u\n",
 		       i, (unsigned long)cfg->address, cfg->pci_segment,
 		       (unsigned int)cfg->start_bus_number,
 		       (unsigned int)cfg->end_bus_number);
 
-		if (!early &&
-		    is_acpi_reserved(cfg->address, cfg->address + size - 1)) {
-			printk(KERN_NOTICE "PCI: MCFG area at %Lx reserved "
-			       "in ACPI motherboard resources\n",
-			       cfg->address);
-			valid = 1;
-		}
+		if (!early)
+			valid = is_mmconf_reserved(is_acpi_reserved, addr, size, i, cfg, 0);
 
 		if (valid)
 			continue;
@@ -347,16 +383,11 @@ static void __init pci_mmcfg_reject_broken(int early)
 			printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %Lx is not"
 			       " reserved in ACPI motherboard resources\n",
 			       cfg->address);
+
 		/* Don't try to do this check unless configuration
 		   type 1 is available. how about type 2 ?*/
-		if (raw_pci_ops && e820_all_mapped(cfg->address,
-						  cfg->address + size - 1,
-						  E820_RESERVED)) {
-			printk(KERN_NOTICE
-			       "PCI: MCFG area at %Lx reserved in E820\n",
-			       cfg->address);
-			valid = 1;
-		}
+		if (raw_pci_ops)
+			valid = is_mmconf_reserved(e820_all_mapped, addr, size, i, cfg, 1);
 
 		if (!valid)
 			goto reject;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index a04498d390c8..cce2f4cb1fbf 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -383,6 +383,7 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 			res->start = base;
 		if (!res->end)
 			res->end = limit + 0xfff;
+		printk(KERN_INFO "PCI: bridge %s io port: [%llx, %llx]\n", pci_name(dev), res->start, res->end);
 	}
 
 	res = child->resource[1];
@@ -394,6 +395,7 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
 		res->start = base;
 		res->end = limit + 0xfffff;
+		printk(KERN_INFO "PCI: bridge %s 32bit mmio: [%llx, %llx]\n", pci_name(dev), res->start, res->end);
 	}
 
 	res = child->resource[2];
@@ -429,6 +431,7 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH;
 		res->start = base;
 		res->end = limit + 0xfffff;
+		printk(KERN_INFO "PCI: bridge %s %sbit mmio pref: [%llx, %llx]\n", pci_name(dev), (res->flags & PCI_PREF_RANGE_TYPE_64)?"64":"32",res->start, res->end);
 	}
 }
 
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 827c0a520e2b..82634a2f1b1d 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -530,6 +530,36 @@ void __ref pci_bus_assign_resources(struct pci_bus *bus)
 }
 EXPORT_SYMBOL(pci_bus_assign_resources);
 
+static void pci_bus_dump_res(struct pci_bus *bus)
+{
+        int i;
+
+        for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
+                struct resource *res = bus->resource[i];
+                if (!res)
+                        continue;
+
+		printk(KERN_INFO "bus: %02x index %x %s: [%llx, %llx]\n", bus->number, i, (res->flags & IORESOURCE_IO)? "io port":"mmio", res->start, res->end);
+        }
+}
+
+static void pci_bus_dump_resources(struct pci_bus *bus)
+{
+	struct pci_bus *b;
+	struct pci_dev *dev;
+
+
+	pci_bus_dump_res(bus);
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		b = dev->subordinate;
+		if (!b)
+			continue;
+
+		pci_bus_dump_resources(b);
+	}
+}
+
 void __init
 pci_assign_unassigned_resources(void)
 {
@@ -545,4 +575,9 @@ pci_assign_unassigned_resources(void)
 		pci_bus_assign_resources(bus);
 		pci_enable_bridges(bus);
 	}
+
+	/* dump the resource on buses */
+	list_for_each_entry(bus, &pci_root_buses, node) {
+		pci_bus_dump_resources(bus);
+	}
 }