8 files changed, 178 insertions, 278 deletions

diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index cfd1b132b8e3..6ac273832f28 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -10,9 +10,6 @@
 struct pci_root_info {
 	struct acpi_device *bridge;
 	char name[16];
-	unsigned int res_num;
-	struct resource *res;
-	resource_size_t *res_offset;
 	struct pci_sysdata sd;
 #ifdef	CONFIG_PCI_MMCONFIG
 	bool mcfg_added;
@@ -218,130 +215,41 @@ static void teardown_mcfg_map(struct pci_root_info *info)
 }
 #endif
 
-static acpi_status resource_to_addr(struct acpi_resource *resource,
-				    struct acpi_resource_address64 *addr)
-{
-	acpi_status status;
-	struct acpi_resource_memory24 *memory24;
-	struct acpi_resource_memory32 *memory32;
-	struct acpi_resource_fixed_memory32 *fixed_memory32;
-
-	memset(addr, 0, sizeof(*addr));
-	switch (resource->type) {
-	case ACPI_RESOURCE_TYPE_MEMORY24:
-		memory24 = &resource->data.memory24;
-		addr->resource_type = ACPI_MEMORY_RANGE;
-		addr->minimum = memory24->minimum;
-		addr->address_length = memory24->address_length;
-		addr->maximum = addr->minimum + addr->address_length - 1;
-		return AE_OK;
-	case ACPI_RESOURCE_TYPE_MEMORY32:
-		memory32 = &resource->data.memory32;
-		addr->resource_type = ACPI_MEMORY_RANGE;
-		addr->minimum = memory32->minimum;
-		addr->address_length = memory32->address_length;
-		addr->maximum = addr->minimum + addr->address_length - 1;
-		return AE_OK;
-	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
-		fixed_memory32 = &resource->data.fixed_memory32;
-		addr->resource_type = ACPI_MEMORY_RANGE;
-		addr->minimum = fixed_memory32->address;
-		addr->address_length = fixed_memory32->address_length;
-		addr->maximum = addr->minimum + addr->address_length - 1;
-		return AE_OK;
-	case ACPI_RESOURCE_TYPE_ADDRESS16:
-	case ACPI_RESOURCE_TYPE_ADDRESS32:
-	case ACPI_RESOURCE_TYPE_ADDRESS64:
-		status = acpi_resource_to_address64(resource, addr);
-		if (ACPI_SUCCESS(status) &&
-		    (addr->resource_type == ACPI_MEMORY_RANGE ||
-		    addr->resource_type == ACPI_IO_RANGE) &&
-		    addr->address_length > 0) {
-			return AE_OK;
-		}
-		break;
-	}
-	return AE_ERROR;
-}
-
-static acpi_status count_resource(struct acpi_resource *acpi_res, void *data)
+static void validate_resources(struct device *dev, struct list_head *crs_res,
+			       unsigned long type)
 {
-	struct pci_root_info *info = data;
-	struct acpi_resource_address64 addr;
-	acpi_status status;
-
-	status = resource_to_addr(acpi_res, &addr);
-	if (ACPI_SUCCESS(status))
-		info->res_num++;
-	return AE_OK;
-}
-
-static acpi_status setup_resource(struct acpi_resource *acpi_res, void *data)
-{
-	struct pci_root_info *info = data;
-	struct resource *res;
-	struct acpi_resource_address64 addr;
-	acpi_status status;
-	unsigned long flags;
-	u64 start, orig_end, end;
-
-	status = resource_to_addr(acpi_res, &addr);
-	if (!ACPI_SUCCESS(status))
-		return AE_OK;
-
-	if (addr.resource_type == ACPI_MEMORY_RANGE) {
-		flags = IORESOURCE_MEM;
-		if (addr.info.mem.caching == ACPI_PREFETCHABLE_MEMORY)
-			flags |= IORESOURCE_PREFETCH;
-	} else if (addr.resource_type == ACPI_IO_RANGE) {
-		flags = IORESOURCE_IO;
-	} else
-		return AE_OK;
-
-	start = addr.minimum + addr.translation_offset;
-	orig_end = end = addr.maximum + addr.translation_offset;
-
-	/* Exclude non-addressable range or non-addressable portion of range */
-	end = min(end, (u64)iomem_resource.end);
-	if (end <= start) {
-		dev_info(&info->bridge->dev,
-			"host bridge window [%#llx-%#llx] "
-			"(ignored, not CPU addressable)\n", start, orig_end);
-		return AE_OK;
-	} else if (orig_end != end) {
-		dev_info(&info->bridge->dev,
-			"host bridge window [%#llx-%#llx] "
-			"([%#llx-%#llx] ignored, not CPU addressable)\n", 
-			start, orig_end, end + 1, orig_end);
-	}
+	LIST_HEAD(list);
+	struct resource *res1, *res2, *root = NULL;
+	struct resource_entry *tmp, *entry, *entry2;
 
-	res = &info->res[info->res_num];
-	res->name = info->name;
-	res->flags = flags;
-	res->start = start;
-	res->end = end;
-	info->res_offset[info->res_num] = addr.translation_offset;
-	info->res_num++;
+	BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
+	root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
 
-	if (!pci_use_crs)
-		dev_printk(KERN_DEBUG, &info->bridge->dev,
-			   "host bridge window %pR (ignored)\n", res);
+	list_splice_init(crs_res, &list);
+	resource_list_for_each_entry_safe(entry, tmp, &list) {
+		bool free = false;
+		resource_size_t end;
 
-	return AE_OK;
-}
-
-static void coalesce_windows(struct pci_root_info *info, unsigned long type)
-{
-	int i, j;
-	struct resource *res1, *res2;
-
-	for (i = 0; i < info->res_num; i++) {
-		res1 = &info->res[i];
+		res1 = entry->res;
 		if (!(res1->flags & type))
-			continue;
+			goto next;
+
+		/* Exclude non-addressable range or non-addressable portion */
+		end = min(res1->end, root->end);
+		if (end <= res1->start) {
+			dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
+				 res1);
+			free = true;
+			goto next;
+		} else if (res1->end != end) {
+			dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
+				 res1, (unsigned long long)end + 1,
+				 (unsigned long long)res1->end);
+			res1->end = end;
+		}
 
-		for (j = i + 1; j < info->res_num; j++) {
-			res2 = &info->res[j];
+		resource_list_for_each_entry(entry2, crs_res) {
+			res2 = entry2->res;
 			if (!(res2->flags & type))
 				continue;
 
@@ -353,118 +261,92 @@ static void coalesce_windows(struct pci_root_info *info, unsigned long type)
 			if (resource_overlaps(res1, res2)) {
 				res2->start = min(res1->start, res2->start);
 				res2->end = max(res1->end, res2->end);
-				dev_info(&info->bridge->dev,
-					 "host bridge window expanded to %pR; %pR ignored\n",
+				dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
 					 res2, res1);
-				res1->flags = 0;
+				free = true;
+				goto next;
 			}
 		}
+
+next:
+		resource_list_del(entry);
+		if (free)
+			resource_list_free_entry(entry);
+		else
+			resource_list_add_tail(entry, crs_res);
 	}
 }
 
 static void add_resources(struct pci_root_info *info,
-			  struct list_head *resources)
+			  struct list_head *resources,
+			  struct list_head *crs_res)
 {
-	int i;
-	struct resource *res, *root, *conflict;
-
-	coalesce_windows(info, IORESOURCE_MEM);
-	coalesce_windows(info, IORESOURCE_IO);
+	struct resource_entry *entry, *tmp;
+	struct resource *res, *conflict, *root = NULL;
 
-	for (i = 0; i < info->res_num; i++) {
-		res = &info->res[i];
+	validate_resources(&info->bridge->dev, crs_res, IORESOURCE_MEM);
+	validate_resources(&info->bridge->dev, crs_res, IORESOURCE_IO);
 
+	resource_list_for_each_entry_safe(entry, tmp, crs_res) {
+		res = entry->res;
 		if (res->flags & IORESOURCE_MEM)
 			root = &iomem_resource;
 		else if (res->flags & IORESOURCE_IO)
 			root = &ioport_resource;
 		else
-			continue;
+			BUG_ON(res);
 
 		conflict = insert_resource_conflict(root, res);
-		if (conflict)
+		if (conflict) {
 			dev_info(&info->bridge->dev,
 				 "ignoring host bridge window %pR (conflicts with %s %pR)\n",
 				 res, conflict->name, conflict);
-		else
-			pci_add_resource_offset(resources, res,
-					info->res_offset[i]);
+			resource_list_destroy_entry(entry);
+		}
 	}
-}
 
-static void free_pci_root_info_res(struct pci_root_info *info)
-{
-	kfree(info->res);
-	info->res = NULL;
-	kfree(info->res_offset);
-	info->res_offset = NULL;
-	info->res_num = 0;
+	list_splice_tail(crs_res, resources);
 }
 
-static void __release_pci_root_info(struct pci_root_info *info)
+static void release_pci_root_info(struct pci_host_bridge *bridge)
 {
-	int i;
 	struct resource *res;
+	struct resource_entry *entry;
+	struct pci_root_info *info = bridge->release_data;
 
-	for (i = 0; i < info->res_num; i++) {
-		res = &info->res[i];
-
-		if (!res->parent)
-			continue;
-
-		if (!(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
-			continue;
-
-		release_resource(res);
+	resource_list_for_each_entry(entry, &bridge->windows) {
+		res = entry->res;
+		if (res->parent &&
+		    (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+			release_resource(res);
 	}
 
-	free_pci_root_info_res(info);
-
 	teardown_mcfg_map(info);
-
 	kfree(info);
 }
 
-static void release_pci_root_info(struct pci_host_bridge *bridge)
-{
-	struct pci_root_info *info = bridge->release_data;
-
-	__release_pci_root_info(info);
-}
-
 static void probe_pci_root_info(struct pci_root_info *info,
 				struct acpi_device *device,
-				int busnum, int domain)
+				int busnum, int domain,
+				struct list_head *list)
 {
-	size_t size;
+	int ret;
+	struct resource_entry *entry;
 
 	sprintf(info->name, "PCI Bus %04x:%02x", domain, busnum);
 	info->bridge = device;
-
-	info->res_num = 0;
-	acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_resource,
-				info);
-	if (!info->res_num)
-		return;
-
-	size = sizeof(*info->res) * info->res_num;
-	info->res = kzalloc_node(size, GFP_KERNEL, info->sd.node);
-	if (!info->res) {
-		info->res_num = 0;
-		return;
-	}
-
-	size = sizeof(*info->res_offset) * info->res_num;
-	info->res_num = 0;
-	info->res_offset = kzalloc_node(size, GFP_KERNEL, info->sd.node);
-	if (!info->res_offset) {
-		kfree(info->res);
-		info->res = NULL;
-		return;
-	}
-
-	acpi_walk_resources(device->handle, METHOD_NAME__CRS, setup_resource,
-				info);
+	ret = acpi_dev_get_resources(device, list,
+				     acpi_dev_filter_resource_type_cb,
+				     (void *)(IORESOURCE_IO | IORESOURCE_MEM));
+	if (ret < 0)
+		dev_warn(&device->dev,
+			 "failed to parse _CRS method, error code %d\n", ret);
+	else if (ret == 0)
+		dev_dbg(&device->dev,
+			"no IO and memory resources present in _CRS\n");
+	else
+		resource_list_for_each_entry(entry, list)
+			entry->res->name = info->name;
 }
 
 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
@@ -473,6 +355,8 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 	struct pci_root_info *info;
 	int domain = root->segment;
 	int busnum = root->secondary.start;
+	struct resource_entry *res_entry;
+	LIST_HEAD(crs_res);
 	LIST_HEAD(resources);
 	struct pci_bus *bus;
 	struct pci_sysdata *sd;
@@ -520,18 +404,22 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 		memcpy(bus->sysdata, sd, sizeof(*sd));
 		kfree(info);
 	} else {
-		probe_pci_root_info(info, device, busnum, domain);
-
 		/* insert busn res at first */
 		pci_add_resource(&resources,  &root->secondary);
+
 		/*
 		 * _CRS with no apertures is normal, so only fall back to
 		 * defaults or native bridge info if we're ignoring _CRS.
 		 */
-		if (pci_use_crs)
-			add_resources(info, &resources);
-		else {
-			free_pci_root_info_res(info);
+		probe_pci_root_info(info, device, busnum, domain, &crs_res);
+		if (pci_use_crs) {
+			add_resources(info, &resources, &crs_res);
+		} else {
+			resource_list_for_each_entry(res_entry, &crs_res)
+				dev_printk(KERN_DEBUG, &device->dev,
+					   "host bridge window %pR (ignored)\n",
+					   res_entry->res);
+			resource_list_free(&crs_res);
 			x86_pci_root_bus_resources(busnum, &resources);
 		}
 
@@ -546,8 +434,9 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 				to_pci_host_bridge(bus->bridge),
 				release_pci_root_info, info);
 		} else {
-			pci_free_resource_list(&resources);
-			__release_pci_root_info(info);
+			resource_list_free(&resources);
+			teardown_mcfg_map(info);
+			kfree(info);
 		}
 	}
 
diff --git a/arch/x86/pci/bus_numa.c b/arch/x86/pci/bus_numa.c
index f3a2cfc14125..7bcf06a7cd12 100644
--- a/arch/x86/pci/bus_numa.c
+++ b/arch/x86/pci/bus_numa.c
@@ -31,7 +31,7 @@ void x86_pci_root_bus_resources(int bus, struct list_head *resources)
 {
 	struct pci_root_info *info = x86_find_pci_root_info(bus);
 	struct pci_root_res *root_res;
-	struct pci_host_bridge_window *window;
+	struct resource_entry *window;
 	bool found = false;
 
 	if (!info)
@@ -41,7 +41,7 @@ void x86_pci_root_bus_resources(int bus, struct list_head *resources)
 	       bus);
 
 	/* already added by acpi ? */
-	list_for_each_entry(window, resources, list)
+	resource_list_for_each_entry(window, resources)
 		if (window->res->flags & IORESOURCE_BUS) {
 			found = true;
 			break;
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 7b20bccf3648..3d2612b68694 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -448,6 +448,22 @@ static const struct dmi_system_id pciprobe_dmi_table[] __initconst = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "ftServer"),
 		},
 	},
+        {
+                .callback = set_scan_all,
+                .ident = "Stratus/NEC ftServer",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Express5800/R32"),
+                },
+        },
+        {
+                .callback = set_scan_all,
+                .ident = "Stratus/NEC ftServer",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Express5800/R31"),
+                },
+        },
 	{}
 };
 
@@ -497,6 +513,31 @@ void __init pcibios_set_cache_line_size(void)
 	}
 }
 
+/*
+ * Some device drivers assume dev->irq won't change after calling
+ * pci_disable_device(). So delay releasing of IRQ resource to driver
+ * unbinding time. Otherwise it will break PM subsystem and drivers
+ * like xen-pciback etc.
+ */
+static int pci_irq_notifier(struct notifier_block *nb, unsigned long action,
+			    void *data)
+{
+	struct pci_dev *dev = to_pci_dev(data);
+
+	if (action != BUS_NOTIFY_UNBOUND_DRIVER)
+		return NOTIFY_DONE;
+
+	if (pcibios_disable_irq)
+		pcibios_disable_irq(dev);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block pci_irq_nb = {
+	.notifier_call = pci_irq_notifier,
+	.priority = INT_MIN,
+};
+
 int __init pcibios_init(void)
 {
 	if (!raw_pci_ops) {
@@ -509,6 +550,9 @@ int __init pcibios_init(void)
 
 	if (pci_bf_sort >= pci_force_bf)
 		pci_sort_breadthfirst();
+
+	bus_register_notifier(&pci_bus_type, &pci_irq_nb);
+
 	return 0;
 }
 
@@ -667,12 +711,6 @@ int pcibios_enable_device(struct pci_dev *dev, int mask)
 	return 0;
 }
 
-void pcibios_disable_device (struct pci_dev *dev)
-{
-	if (!pci_dev_msi_enabled(dev) && pcibios_disable_irq)
-		pcibios_disable_irq(dev);
-}
-
 int pci_ext_cfg_avail(void)
 {
 	if (raw_pci_ext_ops)
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 9b18ef315a55..349c0d32cc0b 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -216,7 +216,7 @@ static void pcibios_allocate_bridge_resources(struct pci_dev *dev)
 			continue;
 		if (r->parent)	/* Already allocated */
 			continue;
-		if (!r->start || pci_claim_resource(dev, idx) < 0) {
+		if (!r->start || pci_claim_bridge_resource(dev, idx) < 0) {
 			/*
 			 * Something is wrong with the region.
 			 * Invalidate the resource to prevent
diff --git a/arch/x86/pci/intel_mid_pci.c b/arch/x86/pci/intel_mid_pci.c
index 44b9271580b5..efb849323c74 100644
--- a/arch/x86/pci/intel_mid_pci.c
+++ b/arch/x86/pci/intel_mid_pci.c
@@ -234,10 +234,10 @@ static int intel_mid_pci_irq_enable(struct pci_dev *dev)
 
 static void intel_mid_pci_irq_disable(struct pci_dev *dev)
 {
-	if (!mp_should_keep_irq(&dev->dev) && dev->irq_managed &&
-	    dev->irq > 0) {
+	if (dev->irq_managed && dev->irq > 0) {
 		mp_unmap_irq(dev->irq);
 		dev->irq_managed = 0;
+		dev->irq = 0;
 	}
 }
 
@@ -293,7 +293,6 @@ static void mrst_power_off_unused_dev(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0801, mrst_power_off_unused_dev);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0809, mrst_power_off_unused_dev);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x080C, mrst_power_off_unused_dev);
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0812, mrst_power_off_unused_dev);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0815, mrst_power_off_unused_dev);
 
 /*
diff --git a/arch/x86/pci/irq.c b/arch/x86/pci/irq.c
index 5dc6ca5e1741..e71b3dbd87b8 100644
--- a/arch/x86/pci/irq.c
+++ b/arch/x86/pci/irq.c
@@ -1256,22 +1256,9 @@ static int pirq_enable_irq(struct pci_dev *dev)
 	return 0;
 }
 
-bool mp_should_keep_irq(struct device *dev)
-{
-	if (dev->power.is_prepared)
-		return true;
-#ifdef CONFIG_PM
-	if (dev->power.runtime_status == RPM_SUSPENDING)
-		return true;
-#endif
-
-	return false;
-}
-
 static void pirq_disable_irq(struct pci_dev *dev)
 {
-	if (io_apic_assign_pci_irqs && !mp_should_keep_irq(&dev->dev) &&
-	    dev->irq_managed && dev->irq) {
+	if (io_apic_assign_pci_irqs && dev->irq_managed && dev->irq) {
 		mp_unmap_irq(dev->irq);
 		dev->irq = 0;
 		dev->irq_managed = 0;
diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 326198a4434e..dd30b7e08bc2 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -397,12 +397,12 @@ static acpi_status check_mcfg_resource(struct acpi_resource *res, void *data)
 
 	status = acpi_resource_to_address64(res, &address);
 	if (ACPI_FAILURE(status) ||
-	   (address.address_length <= 0) ||
+	   (address.address.address_length <= 0) ||
 	   (address.resource_type != ACPI_MEMORY_RANGE))
 		return AE_OK;
 
-	if ((mcfg_res->start >= address.minimum) &&
-	    (mcfg_res->end < (address.minimum + address.address_length))) {
+	if ((mcfg_res->start >= address.address.minimum) &&
+	    (mcfg_res->end < (address.address.minimum + address.address.address_length))) {
 		mcfg_res->flags = 1;
 		return AE_CTRL_TERMINATE;
 	}
@@ -610,6 +610,32 @@ static int __init pci_parse_mcfg(struct acpi_table_header *header)
 	return 0;
 }
 
+#ifdef CONFIG_ACPI_APEI
+extern int (*arch_apei_filter_addr)(int (*func)(__u64 start, __u64 size,
+				     void *data), void *data);
+
+static int pci_mmcfg_for_each_region(int (*func)(__u64 start, __u64 size,
+				     void *data), void *data)
+{
+	struct pci_mmcfg_region *cfg;
+	int rc;
+
+	if (list_empty(&pci_mmcfg_list))
+		return 0;
+
+	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
+		rc = func(cfg->res.start, resource_size(&cfg->res), data);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+#define set_apei_filter() (arch_apei_filter_addr = pci_mmcfg_for_each_region)
+#else
+#define set_apei_filter()
+#endif
+
 static void __init __pci_mmcfg_init(int early)
 {
 	pci_mmcfg_reject_broken(early);
@@ -644,6 +670,8 @@ void __init pci_mmcfg_early_init(void)
 		else
 			acpi_sfi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
 		__pci_mmcfg_init(1);
+
+		set_apei_filter();
 	}
 }
 
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index c489ef2c1a39..d22f4b5bbc04 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -298,12 +298,16 @@ static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 			map_irq.entry_nr = nvec;
 		} else if (type == PCI_CAP_ID_MSIX) {
 			int pos;
+			unsigned long flags;
 			u32 table_offset, bir;
 
 			pos = dev->msix_cap;
 			pci_read_config_dword(dev, pos + PCI_MSIX_TABLE,
 					      &table_offset);
 			bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR);
+			flags = pci_resource_flags(dev, bir);
+			if (!flags || (flags & IORESOURCE_UNSET))
+				return -EINVAL;
 
 			map_irq.table_base = pci_resource_start(dev, bir);
 			map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
@@ -458,6 +462,7 @@ int __init pci_xen_hvm_init(void)
 	 * just how GSIs get registered.
 	 */
 	__acpi_register_gsi = acpi_register_gsi_xen_hvm;
+	__acpi_unregister_gsi = NULL;
 #endif
 
 #ifdef CONFIG_PCI_MSI
@@ -471,52 +476,6 @@ int __init pci_xen_hvm_init(void)
 }
 
 #ifdef CONFIG_XEN_DOM0
-static __init void xen_setup_acpi_sci(void)
-{
-	int rc;
-	int trigger, polarity;
-	int gsi = acpi_sci_override_gsi;
-	int irq = -1;
-	int gsi_override = -1;
-
-	if (!gsi)
-		return;
-
-	rc = acpi_get_override_irq(gsi, &trigger, &polarity);
-	if (rc) {
-		printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi"
-				" sci, rc=%d\n", rc);
-		return;
-	}
-	trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
-	polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
-
-	printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d "
-			"polarity=%d\n", gsi, trigger, polarity);
-
-	/* Before we bind the GSI to a Linux IRQ, check whether
-	 * we need to override it with bus_irq (IRQ) value. Usually for
-	 * IRQs below IRQ_LEGACY_IRQ this holds IRQ == GSI, as so:
-	 *  ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level)
-	 * but there are oddballs where the IRQ != GSI:
-	 *  ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level)
-	 * which ends up being: gsi_to_irq[9] == 20
-	 * (which is what acpi_gsi_to_irq ends up calling when starting the
-	 * the ACPI interpreter and keels over since IRQ 9 has not been
-	 * setup as we had setup IRQ 20 for it).
-	 */
-	if (acpi_gsi_to_irq(gsi, &irq) == 0) {
-		/* Use the provided value if it's valid. */
-		if (irq >= 0)
-			gsi_override = irq;
-	}
-
-	gsi = xen_register_gsi(gsi, gsi_override, trigger, polarity);
-	printk(KERN_INFO "xen: acpi sci %d\n", gsi);
-
-	return;
-}
-
 int __init pci_xen_initial_domain(void)
 {
 	int irq;
@@ -527,8 +486,8 @@ int __init pci_xen_initial_domain(void)
 	x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs;
 	pci_msi_ignore_mask = 1;
 #endif
-	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
+	__acpi_unregister_gsi = NULL;
 	/* Pre-allocate legacy irqs */
 	for (irq = 0; irq < nr_legacy_irqs(); irq++) {
 		int trigger, polarity;