libnvdimm for 4.13

* Introduce the _flushcache() family of memory copy helpers and use them
   for persistent memory write operations on x86. The _flushcache()
   semantic indicates that the cache is either bypassed for the copy
   operation (movnt) or any lines dirtied by the copy operation are
   written back (clwb, clflushopt, or clflush).
 
 * Extend dax_operations with ->copy_from_iter() and ->flush()
   operations. These operations and other infrastructure updates allow
   all persistent memory specific dax functionality to be pushed into
   libnvdimm and the pmem driver directly. It also allows dax-specific
   sysfs attributes to be linked to a host device, for example:
       /sys/block/pmem0/dax/write_cache
 
 * Add support for the new NVDIMM platform/firmware mechanisms introduced
   in ACPI 6.2 and UEFI 2.7. This support includes the v1.2 namespace
   label format, extensions to the address-range-scrub command set, new
   error injection commands, and a new BTT (block-translation-table)
   layout. These updates support inter-OS and pre-OS compatibility.
 
 * Fix a longstanding memory corruption bug in nfit_test.
 
 * Make the pmem and nvdimm-region 'badblocks' sysfs files poll(2)
   capable.
 
 * Miscellaneous fixes and small updates across libnvdimm and the nfit
   driver.
 
 Acknowledgements that came after the branch was pushed:
 
 commit 6aa734a2f3 "libnvdimm, region, pmem: fix 'badblocks'
   sysfs_get_dirent() reference lifetime"
 Reviewed-by: Toshi Kani <[email protected]>
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Merge tag 'libnvdimm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "libnvdimm updates for the latest ACPI and UEFI specifications. This
  pull request also includes new 'struct dax_operations' enabling to
  undo the abuse of copy_user_nocache() for copy operations to pmem.

  The dax work originally missed 4.12 to address concerns raised by Al.

  Summary:

   - Introduce the _flushcache() family of memory copy helpers and use
     them for persistent memory write operations on x86. The
     _flushcache() semantic indicates that the cache is either bypassed
     for the copy operation (movnt) or any lines dirtied by the copy
     operation are written back (clwb, clflushopt, or clflush).

   - Extend dax_operations with ->copy_from_iter() and ->flush()
     operations. These operations and other infrastructure updates allow
     all persistent memory specific dax functionality to be pushed into
     libnvdimm and the pmem driver directly. It also allows dax-specific
     sysfs attributes to be linked to a host device, for example:
     /sys/block/pmem0/dax/write_cache

   - Add support for the new NVDIMM platform/firmware mechanisms
     introduced in ACPI 6.2 and UEFI 2.7. This support includes the v1.2
     namespace label format, extensions to the address-range-scrub
     command set, new error injection commands, and a new BTT
     (block-translation-table) layout. These updates support inter-OS
     and pre-OS compatibility.

   - Fix a longstanding memory corruption bug in nfit_test.

   - Make the pmem and nvdimm-region 'badblocks' sysfs files poll(2)
     capable.

   - Miscellaneous fixes and small updates across libnvdimm and the nfit
     driver.

  Acknowledgements that came after the branch was pushed: commit
  6aa734a2f3 ("libnvdimm, region, pmem: fix 'badblocks'
  sysfs_get_dirent() reference lifetime") was reviewed by Toshi Kani
  <[email protected]>"

* tag 'libnvdimm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (42 commits)
  libnvdimm, namespace: record 'lbasize' for pmem namespaces
  acpi/nfit: Issue Start ARS to retrieve existing records
  libnvdimm: New ACPI 6.2 DSM functions
  acpi, nfit: Show bus_dsm_mask in sysfs
  libnvdimm, acpi, nfit: Add bus level dsm mask for pass thru.
  acpi, nfit: Enable DSM pass thru for root functions.
  libnvdimm: passthru functions clear to send
  libnvdimm, btt: convert some info messages to warn/err
  libnvdimm, region, pmem: fix 'badblocks' sysfs_get_dirent() reference lifetime
  libnvdimm: fix the clear-error check in nsio_rw_bytes
  libnvdimm, btt: fix btt_rw_page not returning errors
  acpi, nfit: quiet invalid block-aperture-region warnings
  libnvdimm, btt: BTT updates for UEFI 2.7 format
  acpi, nfit: constify *_attribute_group
  libnvdimm, pmem: disable dax flushing when pmem is fronting a volatile region
  libnvdimm, pmem, dax: export a cache control attribute
  dax: convert to bitmask for flags
  dax: remove default copy_from_iter fallback
  libnvdimm, nfit: enable support for volatile ranges
  libnvdimm, pmem: fix persistence warning
  ...

drivers/acpi/nfit/core.c

@@ -20,7 +20,6 @@
 #include <linux/list.h>
 #include <linux/acpi.h>
 #include <linux/sort.h>
-#include <linux/pmem.h>
 #include <linux/io.h>
 #include <linux/nd.h>
 #include <asm/cacheflush.h>
@@ -253,6 +252,8 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
 		cmd_name = nvdimm_bus_cmd_name(cmd);
 		cmd_mask = nd_desc->cmd_mask;
 		dsm_mask = cmd_mask;
+		if (cmd == ND_CMD_CALL)
+			dsm_mask = nd_desc->bus_dsm_mask;
 		desc = nd_cmd_bus_desc(cmd);
 		guid = to_nfit_uuid(NFIT_DEV_BUS);
 		handle = adev->handle;
@@ -927,6 +928,17 @@ static int nfit_mem_init(struct acpi_nfit_desc *acpi_desc)
 	return 0;
 }
 
+static ssize_t bus_dsm_mask_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
+	struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
+
+	return sprintf(buf, "%#lx\n", nd_desc->bus_dsm_mask);
+}
+static struct device_attribute dev_attr_bus_dsm_mask =
+		__ATTR(dsm_mask, 0444, bus_dsm_mask_show, NULL);
+
 static ssize_t revision_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
@@ -1031,7 +1043,7 @@ static ssize_t scrub_store(struct device *dev,
 	if (nd_desc) {
 		struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
 
-		rc = acpi_nfit_ars_rescan(acpi_desc);
+		rc = acpi_nfit_ars_rescan(acpi_desc, 0);
 	}
 	device_unlock(dev);
 	if (rc)
@@ -1063,10 +1075,11 @@ static struct attribute *acpi_nfit_attributes[] = {
 	&dev_attr_revision.attr,
 	&dev_attr_scrub.attr,
 	&dev_attr_hw_error_scrub.attr,
+	&dev_attr_bus_dsm_mask.attr,
 	NULL,
 };
 
-static struct attribute_group acpi_nfit_attribute_group = {
+static const struct attribute_group acpi_nfit_attribute_group = {
 	.name = "nfit",
 	.attrs = acpi_nfit_attributes,
 	.is_visible = nfit_visible,
@@ -1346,7 +1359,7 @@ static umode_t acpi_nfit_dimm_attr_visible(struct kobject *kobj,
 	return a->mode;
 }
 
-static struct attribute_group acpi_nfit_dimm_attribute_group = {
+static const struct attribute_group acpi_nfit_dimm_attribute_group = {
 	.name = "nfit",
 	.attrs = acpi_nfit_dimm_attributes,
 	.is_visible = acpi_nfit_dimm_attr_visible,
@@ -1608,11 +1621,23 @@ static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
 			acpi_desc);
 }
 
+/*
+ * These constants are private because there are no kernel consumers of
+ * these commands.
+ */
+enum nfit_aux_cmds {
+        NFIT_CMD_TRANSLATE_SPA = 5,
+        NFIT_CMD_ARS_INJECT_SET = 7,
+        NFIT_CMD_ARS_INJECT_CLEAR = 8,
+        NFIT_CMD_ARS_INJECT_GET = 9,
+};
+
 static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
 {
 	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
 	const guid_t *guid = to_nfit_uuid(NFIT_DEV_BUS);
 	struct acpi_device *adev;
+	unsigned long dsm_mask;
 	int i;
 
 	nd_desc->cmd_mask = acpi_desc->bus_cmd_force_en;
@@ -1623,6 +1648,20 @@ static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
 	for (i = ND_CMD_ARS_CAP; i <= ND_CMD_CLEAR_ERROR; i++)
 		if (acpi_check_dsm(adev->handle, guid, 1, 1ULL << i))
 			set_bit(i, &nd_desc->cmd_mask);
+	set_bit(ND_CMD_CALL, &nd_desc->cmd_mask);
+
+	dsm_mask =
+		(1 << ND_CMD_ARS_CAP) |
+		(1 << ND_CMD_ARS_START) |
+		(1 << ND_CMD_ARS_STATUS) |
+		(1 << ND_CMD_CLEAR_ERROR) |
+		(1 << NFIT_CMD_TRANSLATE_SPA) |
+		(1 << NFIT_CMD_ARS_INJECT_SET) |
+		(1 << NFIT_CMD_ARS_INJECT_CLEAR) |
+		(1 << NFIT_CMD_ARS_INJECT_GET);
+	for_each_set_bit(i, &dsm_mask, BITS_PER_LONG)
+		if (acpi_check_dsm(adev->handle, guid, 1, 1ULL << i))
+			set_bit(i, &nd_desc->bus_dsm_mask);
 }
 
 static ssize_t range_index_show(struct device *dev,
@@ -1640,7 +1679,7 @@ static struct attribute *acpi_nfit_region_attributes[] = {
 	NULL,
 };
 
-static struct attribute_group acpi_nfit_region_attribute_group = {
+static const struct attribute_group acpi_nfit_region_attribute_group = {
 	.name = "nfit",
 	.attrs = acpi_nfit_region_attributes,
 };
@@ -1663,12 +1702,29 @@ struct nfit_set_info {
 	} mapping[0];
 };
 
+struct nfit_set_info2 {
+	struct nfit_set_info_map2 {
+		u64 region_offset;
+		u32 serial_number;
+		u16 vendor_id;
+		u16 manufacturing_date;
+		u8  manufacturing_location;
+		u8  reserved[31];
+	} mapping[0];
+};
+
 static size_t sizeof_nfit_set_info(int num_mappings)
 {
 	return sizeof(struct nfit_set_info)
 		+ num_mappings * sizeof(struct nfit_set_info_map);
 }
 
+static size_t sizeof_nfit_set_info2(int num_mappings)
+{
+	return sizeof(struct nfit_set_info2)
+		+ num_mappings * sizeof(struct nfit_set_info_map2);
+}
+
 static int cmp_map_compat(const void *m0, const void *m1)
 {
 	const struct nfit_set_info_map *map0 = m0;
@@ -1690,6 +1746,18 @@ static int cmp_map(const void *m0, const void *m1)
 	return 0;
 }
 
+static int cmp_map2(const void *m0, const void *m1)
+{
+	const struct nfit_set_info_map2 *map0 = m0;
+	const struct nfit_set_info_map2 *map1 = m1;
+
+	if (map0->region_offset < map1->region_offset)
+		return -1;
+	else if (map0->region_offset > map1->region_offset)
+		return 1;
+	return 0;
+}
+
 /* Retrieve the nth entry referencing this spa */
 static struct acpi_nfit_memory_map *memdev_from_spa(
 		struct acpi_nfit_desc *acpi_desc, u16 range_index, int n)
@@ -1707,27 +1775,31 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
 		struct nd_region_desc *ndr_desc,
 		struct acpi_nfit_system_address *spa)
 {
-	int i, spa_type = nfit_spa_type(spa);
 	struct device *dev = acpi_desc->dev;
 	struct nd_interleave_set *nd_set;
 	u16 nr = ndr_desc->num_mappings;
+	struct nfit_set_info2 *info2;
 	struct nfit_set_info *info;
-
-	if (spa_type == NFIT_SPA_PM || spa_type == NFIT_SPA_VOLATILE)
-		/* pass */;
-	else
-		return 0;
+	int i;
 
 	nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
 	if (!nd_set)
 		return -ENOMEM;
+	ndr_desc->nd_set = nd_set;
+	guid_copy(&nd_set->type_guid, (guid_t *) spa->range_guid);
 
 	info = devm_kzalloc(dev, sizeof_nfit_set_info(nr), GFP_KERNEL);
 	if (!info)
 		return -ENOMEM;
+
+	info2 = devm_kzalloc(dev, sizeof_nfit_set_info2(nr), GFP_KERNEL);
+	if (!info2)
+		return -ENOMEM;
+
 	for (i = 0; i < nr; i++) {
 		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
 		struct nfit_set_info_map *map = &info->mapping[i];
+		struct nfit_set_info_map2 *map2 = &info2->mapping[i];
 		struct nvdimm *nvdimm = mapping->nvdimm;
 		struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
 		struct acpi_nfit_memory_map *memdev = memdev_from_spa(acpi_desc,
@@ -1740,19 +1812,32 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
 
 		map->region_offset = memdev->region_offset;
 		map->serial_number = nfit_mem->dcr->serial_number;
+
+		map2->region_offset = memdev->region_offset;
+		map2->serial_number = nfit_mem->dcr->serial_number;
+		map2->vendor_id = nfit_mem->dcr->vendor_id;
+		map2->manufacturing_date = nfit_mem->dcr->manufacturing_date;
+		map2->manufacturing_location = nfit_mem->dcr->manufacturing_location;
 	}
 
+	/* v1.1 namespaces */
 	sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
 			cmp_map, NULL);
-	nd_set->cookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
+	nd_set->cookie1 = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
 
-	/* support namespaces created with the wrong sort order */
+	/* v1.2 namespaces */
+	sort(&info2->mapping[0], nr, sizeof(struct nfit_set_info_map2),
+			cmp_map2, NULL);
+	nd_set->cookie2 = nd_fletcher64(info2, sizeof_nfit_set_info2(nr), 0);
+
+	/* support v1.1 namespaces created with the wrong sort order */
 	sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
 			cmp_map_compat, NULL);
 	nd_set->altcookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
 
 	ndr_desc->nd_set = nd_set;
 	devm_kfree(dev, info);
+	devm_kfree(dev, info2);
 
 	return 0;
 }
@@ -1842,8 +1927,7 @@ static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
 		}
 
 		if (rw)
-			memcpy_to_pmem(mmio->addr.aperture + offset,
-					iobuf + copied, c);
+			memcpy_flushcache(mmio->addr.aperture + offset, iobuf + copied, c);
 		else {
 			if (nfit_blk->dimm_flags & NFIT_BLK_READ_FLUSH)
 				mmio_flush_range((void __force *)
@@ -1957,7 +2041,7 @@ static int acpi_nfit_blk_region_enable(struct nvdimm_bus *nvdimm_bus,
 	nfit_blk->bdw_offset = nfit_mem->bdw->offset;
 	mmio = &nfit_blk->mmio[BDW];
 	mmio->addr.base = devm_nvdimm_memremap(dev, nfit_mem->spa_bdw->address,
-                        nfit_mem->spa_bdw->length, ARCH_MEMREMAP_PMEM);
+                        nfit_mem->spa_bdw->length, nd_blk_memremap_flags(ndbr));
 	if (!mmio->addr.base) {
 		dev_dbg(dev, "%s: %s failed to map bdw\n", __func__,
 				nvdimm_name(nvdimm));
@@ -2051,6 +2135,7 @@ static int ars_start(struct acpi_nfit_desc *acpi_desc, struct nfit_spa *nfit_spa
 	memset(&ars_start, 0, sizeof(ars_start));
 	ars_start.address = spa->address;
 	ars_start.length = spa->length;
+	ars_start.flags = acpi_desc->ars_start_flags;
 	if (nfit_spa_type(spa) == NFIT_SPA_PM)
 		ars_start.type = ND_ARS_PERSISTENT;
 	else if (nfit_spa_type(spa) == NFIT_SPA_VOLATILE)
@@ -2077,6 +2162,7 @@ static int ars_continue(struct acpi_nfit_desc *acpi_desc)
 	ars_start.address = ars_status->restart_address;
 	ars_start.length = ars_status->restart_length;
 	ars_start.type = ars_status->type;
+	ars_start.flags = acpi_desc->ars_start_flags;
 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_START, &ars_start,
 			sizeof(ars_start), &cmd_rc);
 	if (rc < 0)
@@ -2179,7 +2265,7 @@ static int acpi_nfit_init_mapping(struct acpi_nfit_desc *acpi_desc,
 	struct acpi_nfit_system_address *spa = nfit_spa->spa;
 	struct nd_blk_region_desc *ndbr_desc;
 	struct nfit_mem *nfit_mem;
-	int blk_valid = 0;
+	int blk_valid = 0, rc;
 
 	if (!nvdimm) {
 		dev_err(acpi_desc->dev, "spa%d dimm: %#x not found\n",
@@ -2211,6 +2297,9 @@ static int acpi_nfit_init_mapping(struct acpi_nfit_desc *acpi_desc,
 		ndbr_desc = to_blk_region_desc(ndr_desc);
 		ndbr_desc->enable = acpi_nfit_blk_region_enable;
 		ndbr_desc->do_io = acpi_desc->blk_do_io;
+		rc = acpi_nfit_init_interleave_set(acpi_desc, ndr_desc, spa);
+		if (rc)
+			return rc;
 		nfit_spa->nd_region = nvdimm_blk_region_create(acpi_desc->nvdimm_bus,
 				ndr_desc);
 		if (!nfit_spa->nd_region)
@@ -2229,6 +2318,13 @@ static bool nfit_spa_is_virtual(struct acpi_nfit_system_address *spa)
 		nfit_spa_type(spa) == NFIT_SPA_PCD);
 }
 
+static bool nfit_spa_is_volatile(struct acpi_nfit_system_address *spa)
+{
+	return (nfit_spa_type(spa) == NFIT_SPA_VDISK ||
+		nfit_spa_type(spa) == NFIT_SPA_VCD   ||
+		nfit_spa_type(spa) == NFIT_SPA_VOLATILE);
+}
+
 static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc,
 		struct nfit_spa *nfit_spa)
 {
@@ -2303,7 +2399,7 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc,
 				ndr_desc);
 		if (!nfit_spa->nd_region)
 			rc = -ENOMEM;
-	} else if (nfit_spa_type(spa) == NFIT_SPA_VOLATILE) {
+	} else if (nfit_spa_is_volatile(spa)) {
 		nfit_spa->nd_region = nvdimm_volatile_region_create(nvdimm_bus,
 				ndr_desc);
 		if (!nfit_spa->nd_region)
@@ -2595,6 +2691,7 @@ static void acpi_nfit_scrub(struct work_struct *work)
 	list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
 		acpi_nfit_async_scrub(acpi_desc, nfit_spa);
 	acpi_desc->scrub_count++;
+	acpi_desc->ars_start_flags = 0;
 	if (acpi_desc->scrub_count_state)
 		sysfs_notify_dirent(acpi_desc->scrub_count_state);
 	mutex_unlock(&acpi_desc->init_mutex);
@@ -2613,6 +2710,7 @@ static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
 				return rc;
 		}
 
+	acpi_desc->ars_start_flags = 0;
 	if (!acpi_desc->cancel)
 		queue_work(nfit_wq, &acpi_desc->work);
 	return 0;
@@ -2817,7 +2915,7 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
 	return 0;
 }
 
-int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc)
+int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc, u8 flags)
 {
 	struct device *dev = acpi_desc->dev;
 	struct nfit_spa *nfit_spa;
@@ -2839,6 +2937,7 @@ int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc)
 
 		nfit_spa->ars_required = 1;
 	}
+	acpi_desc->ars_start_flags = flags;
 	queue_work(nfit_wq, &acpi_desc->work);
 	dev_dbg(dev, "%s: ars_scan triggered\n", __func__);
 	mutex_unlock(&acpi_desc->init_mutex);
@@ -2967,7 +3066,7 @@ static int acpi_nfit_remove(struct acpi_device *adev)
 	return 0;
 }
 
-void __acpi_nfit_notify(struct device *dev, acpi_handle handle, u32 event)
+static void acpi_nfit_update_notify(struct device *dev, acpi_handle handle)
 {
 	struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(dev);
 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
@@ -2975,11 +3074,6 @@ void __acpi_nfit_notify(struct device *dev, acpi_handle handle, u32 event)
 	acpi_status status;
 	int ret;
 
-	dev_dbg(dev, "%s: event: %d\n", __func__, event);
-
-	if (event != NFIT_NOTIFY_UPDATE)
-		return;
-
 	if (!dev->driver) {
 		/* dev->driver may be null if we're being removed */
 		dev_dbg(dev, "%s: no driver found for dev\n", __func__);
@@ -3016,6 +3110,29 @@ void __acpi_nfit_notify(struct device *dev, acpi_handle handle, u32 event)
 		dev_err(dev, "Invalid _FIT\n");
 	kfree(buf.pointer);
 }
+
+static void acpi_nfit_uc_error_notify(struct device *dev, acpi_handle handle)
+{
+	struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(dev);
+	u8 flags = (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON) ?
+			0 : ND_ARS_RETURN_PREV_DATA;
+
+	acpi_nfit_ars_rescan(acpi_desc, flags);
+}
+
+void __acpi_nfit_notify(struct device *dev, acpi_handle handle, u32 event)
+{
+	dev_dbg(dev, "%s: event: 0x%x\n", __func__, event);
+
+	switch (event) {
+	case NFIT_NOTIFY_UPDATE:
+		return acpi_nfit_update_notify(dev, handle);
+	case NFIT_NOTIFY_UC_MEMORY_ERROR:
+		return acpi_nfit_uc_error_notify(dev, handle);
+	default:
+		return;
+	}
+}
 EXPORT_SYMBOL_GPL(__acpi_nfit_notify);
 
 static void acpi_nfit_notify(struct acpi_device *adev, u32 event)

drivers/acpi/nfit/mce.c

@@ -79,7 +79,7 @@ static int nfit_handle_mce(struct notifier_block *nb, unsigned long val,
 			 * already in progress, just let that be the last
 			 * authoritative one
 			 */
-			acpi_nfit_ars_rescan(acpi_desc);
+			acpi_nfit_ars_rescan(acpi_desc, 0);
 		}
 		break;
 	}

drivers/acpi/nfit/nfit.h

@@ -79,6 +79,7 @@ enum {
 
 enum nfit_root_notifiers {
 	NFIT_NOTIFY_UPDATE = 0x80,
+	NFIT_NOTIFY_UC_MEMORY_ERROR = 0x81,
 };
 
 enum nfit_dimm_notifiers {
@@ -154,6 +155,7 @@ struct acpi_nfit_desc {
 	struct list_head idts;
 	struct nvdimm_bus *nvdimm_bus;
 	struct device *dev;
+	u8 ars_start_flags;
 	struct nd_cmd_ars_status *ars_status;
 	size_t ars_status_size;
 	struct work_struct work;
@@ -206,7 +208,7 @@ struct nfit_blk {
 
 extern struct list_head acpi_descs;
 extern struct mutex acpi_desc_lock;
-int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc);
+int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc, u8 flags);
 
 #ifdef CONFIG_X86_MCE
 void nfit_mce_register(void);