Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:

 - NFIT parsing regression fixes from Linda.  The nvdimm hot-add
   implementation merged in 4.4-rc1 interpreted the specification in a
   way that breaks actual HPE platforms.  We are also closing the loop
   with the ACPI Working Group to get this clarification added to the
   spec.

 - Andy pointed out that his laptop without nvdimm resources is loading
   the e820-nvdimm module by default, fix that up to only load the
   module when an e820-type-12 range is present.

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  nfit: Adjust for different _FIT and NFIT headers
  nfit: Fix the check for a successful NFIT merge
  nfit: Account for table size length variation
  libnvdimm, e820: skip module loading when no type-12
diff --git a/arch/x86/kernel/pmem.c b/arch/x86/kernel/pmem.c
index 4f00b63..14415af 100644
--- a/arch/x86/kernel/pmem.c
+++ b/arch/x86/kernel/pmem.c
@@ -4,10 +4,22 @@
  */
 #include <linux/platform_device.h>
 #include <linux/module.h>
+#include <linux/ioport.h>
+
+static int found(u64 start, u64 end, void *data)
+{
+	return 1;
+}
 
 static __init int register_e820_pmem(void)
 {
+	char *pmem = "Persistent Memory (legacy)";
 	struct platform_device *pdev;
+	int rc;
+
+	rc = walk_iomem_res(pmem, IORESOURCE_MEM, 0, -1, NULL, found);
+	if (rc <= 0)
+		return 0;
 
 	/*
 	 * See drivers/nvdimm/e820.c for the implementation, this is
diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index f7dab53..e7ed39b 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -233,11 +233,12 @@
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_system_address *spa)
 {
+	size_t length = min_t(size_t, sizeof(*spa), spa->header.length);
 	struct device *dev = acpi_desc->dev;
 	struct nfit_spa *nfit_spa;
 
 	list_for_each_entry(nfit_spa, &prev->spas, list) {
-		if (memcmp(nfit_spa->spa, spa, sizeof(*spa)) == 0) {
+		if (memcmp(nfit_spa->spa, spa, length) == 0) {
 			list_move_tail(&nfit_spa->list, &acpi_desc->spas);
 			return true;
 		}
@@ -259,11 +260,12 @@
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_memory_map *memdev)
 {
+	size_t length = min_t(size_t, sizeof(*memdev), memdev->header.length);
 	struct device *dev = acpi_desc->dev;
 	struct nfit_memdev *nfit_memdev;
 
 	list_for_each_entry(nfit_memdev, &prev->memdevs, list)
-		if (memcmp(nfit_memdev->memdev, memdev, sizeof(*memdev)) == 0) {
+		if (memcmp(nfit_memdev->memdev, memdev, length) == 0) {
 			list_move_tail(&nfit_memdev->list, &acpi_desc->memdevs);
 			return true;
 		}
@@ -284,11 +286,12 @@
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_control_region *dcr)
 {
+	size_t length = min_t(size_t, sizeof(*dcr), dcr->header.length);
 	struct device *dev = acpi_desc->dev;
 	struct nfit_dcr *nfit_dcr;
 
 	list_for_each_entry(nfit_dcr, &prev->dcrs, list)
-		if (memcmp(nfit_dcr->dcr, dcr, sizeof(*dcr)) == 0) {
+		if (memcmp(nfit_dcr->dcr, dcr, length) == 0) {
 			list_move_tail(&nfit_dcr->list, &acpi_desc->dcrs);
 			return true;
 		}
@@ -308,11 +311,12 @@
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_data_region *bdw)
 {
+	size_t length = min_t(size_t, sizeof(*bdw), bdw->header.length);
 	struct device *dev = acpi_desc->dev;
 	struct nfit_bdw *nfit_bdw;
 
 	list_for_each_entry(nfit_bdw, &prev->bdws, list)
-		if (memcmp(nfit_bdw->bdw, bdw, sizeof(*bdw)) == 0) {
+		if (memcmp(nfit_bdw->bdw, bdw, length) == 0) {
 			list_move_tail(&nfit_bdw->list, &acpi_desc->bdws);
 			return true;
 		}
@@ -332,11 +336,12 @@
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_interleave *idt)
 {
+	size_t length = min_t(size_t, sizeof(*idt), idt->header.length);
 	struct device *dev = acpi_desc->dev;
 	struct nfit_idt *nfit_idt;
 
 	list_for_each_entry(nfit_idt, &prev->idts, list)
-		if (memcmp(nfit_idt->idt, idt, sizeof(*idt)) == 0) {
+		if (memcmp(nfit_idt->idt, idt, length) == 0) {
 			list_move_tail(&nfit_idt->list, &acpi_desc->idts);
 			return true;
 		}
@@ -356,11 +361,12 @@
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_flush_address *flush)
 {
+	size_t length = min_t(size_t, sizeof(*flush), flush->header.length);
 	struct device *dev = acpi_desc->dev;
 	struct nfit_flush *nfit_flush;
 
 	list_for_each_entry(nfit_flush, &prev->flushes, list)
-		if (memcmp(nfit_flush->flush, flush, sizeof(*flush)) == 0) {
+		if (memcmp(nfit_flush->flush, flush, length) == 0) {
 			list_move_tail(&nfit_flush->list, &acpi_desc->flushes);
 			return true;
 		}
@@ -655,7 +661,7 @@
 	struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
 	struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
 
-	return sprintf(buf, "%d\n", acpi_desc->nfit->header.revision);
+	return sprintf(buf, "%d\n", acpi_desc->acpi_header.revision);
 }
 static DEVICE_ATTR_RO(revision);
 
@@ -1652,7 +1658,6 @@
 
 	data = (u8 *) acpi_desc->nfit;
 	end = data + sz;
-	data += sizeof(struct acpi_table_nfit);
 	while (!IS_ERR_OR_NULL(data))
 		data = add_table(acpi_desc, &prev, data, end);
 
@@ -1748,13 +1753,29 @@
 		return PTR_ERR(acpi_desc);
 	}
 
-	acpi_desc->nfit = (struct acpi_table_nfit *) tbl;
+	/*
+	 * Save the acpi header for later and then skip it,
+	 * making nfit point to the first nfit table header.
+	 */
+	acpi_desc->acpi_header = *tbl;
+	acpi_desc->nfit = (void *) tbl + sizeof(struct acpi_table_nfit);
+	sz -= sizeof(struct acpi_table_nfit);
 
 	/* Evaluate _FIT and override with that if present */
 	status = acpi_evaluate_object(adev->handle, "_FIT", NULL, &buf);
 	if (ACPI_SUCCESS(status) && buf.length > 0) {
-		acpi_desc->nfit = (struct acpi_table_nfit *)buf.pointer;
-		sz = buf.length;
+		union acpi_object *obj;
+		/*
+		 * Adjust for the acpi_object header of the _FIT
+		 */
+		obj = buf.pointer;
+		if (obj->type == ACPI_TYPE_BUFFER) {
+			acpi_desc->nfit =
+				(struct acpi_nfit_header *)obj->buffer.pointer;
+			sz = obj->buffer.length;
+		} else
+			dev_dbg(dev, "%s invalid type %d, ignoring _FIT\n",
+				 __func__, (int) obj->type);
 	}
 
 	rc = acpi_nfit_init(acpi_desc, sz);
@@ -1777,7 +1798,8 @@
 {
 	struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(&adev->dev);
 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
-	struct acpi_table_nfit *nfit_saved;
+	struct acpi_nfit_header *nfit_saved;
+	union acpi_object *obj;
 	struct device *dev = &adev->dev;
 	acpi_status status;
 	int ret;
@@ -1808,12 +1830,19 @@
 	}
 
 	nfit_saved = acpi_desc->nfit;
-	acpi_desc->nfit = (struct acpi_table_nfit *)buf.pointer;
-	ret = acpi_nfit_init(acpi_desc, buf.length);
-	if (!ret) {
-		/* Merge failed, restore old nfit, and exit */
-		acpi_desc->nfit = nfit_saved;
-		dev_err(dev, "failed to merge updated NFIT\n");
+	obj = buf.pointer;
+	if (obj->type == ACPI_TYPE_BUFFER) {
+		acpi_desc->nfit =
+			(struct acpi_nfit_header *)obj->buffer.pointer;
+		ret = acpi_nfit_init(acpi_desc, obj->buffer.length);
+		if (ret) {
+			/* Merge failed, restore old nfit, and exit */
+			acpi_desc->nfit = nfit_saved;
+			dev_err(dev, "failed to merge updated NFIT\n");
+		}
+	} else {
+		/* Bad _FIT, restore old nfit */
+		dev_err(dev, "Invalid _FIT\n");
 	}
 	kfree(buf.pointer);
 
diff --git a/drivers/acpi/nfit.h b/drivers/acpi/nfit.h
index 2ea5c07..3d549a3 100644
--- a/drivers/acpi/nfit.h
+++ b/drivers/acpi/nfit.h
@@ -96,7 +96,8 @@
 
 struct acpi_nfit_desc {
 	struct nvdimm_bus_descriptor nd_desc;
-	struct acpi_table_nfit *nfit;
+	struct acpi_table_header acpi_header;
+	struct acpi_nfit_header *nfit;
 	struct mutex spa_map_mutex;
 	struct mutex init_mutex;
 	struct list_head spa_maps;
diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index 40ab447..51cf825 100644
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -420,8 +420,7 @@
 
 static int nfit_test0_alloc(struct nfit_test *t)
 {
-	size_t nfit_size = sizeof(struct acpi_table_nfit)
-			+ sizeof(struct acpi_nfit_system_address) * NUM_SPA
+	size_t nfit_size = sizeof(struct acpi_nfit_system_address) * NUM_SPA
 			+ sizeof(struct acpi_nfit_memory_map) * NUM_MEM
 			+ sizeof(struct acpi_nfit_control_region) * NUM_DCR
 			+ sizeof(struct acpi_nfit_data_region) * NUM_BDW
@@ -471,8 +470,7 @@
 
 static int nfit_test1_alloc(struct nfit_test *t)
 {
-	size_t nfit_size = sizeof(struct acpi_table_nfit)
-		+ sizeof(struct acpi_nfit_system_address)
+	size_t nfit_size = sizeof(struct acpi_nfit_system_address)
 		+ sizeof(struct acpi_nfit_memory_map)
 		+ sizeof(struct acpi_nfit_control_region);
 
@@ -488,39 +486,24 @@
 	return 0;
 }
 
-static void nfit_test_init_header(struct acpi_table_nfit *nfit, size_t size)
-{
-	memcpy(nfit->header.signature, ACPI_SIG_NFIT, 4);
-	nfit->header.length = size;
-	nfit->header.revision = 1;
-	memcpy(nfit->header.oem_id, "LIBND", 6);
-	memcpy(nfit->header.oem_table_id, "TEST", 5);
-	nfit->header.oem_revision = 1;
-	memcpy(nfit->header.asl_compiler_id, "TST", 4);
-	nfit->header.asl_compiler_revision = 1;
-}
-
 static void nfit_test0_setup(struct nfit_test *t)
 {
 	struct nvdimm_bus_descriptor *nd_desc;
 	struct acpi_nfit_desc *acpi_desc;
 	struct acpi_nfit_memory_map *memdev;
 	void *nfit_buf = t->nfit_buf;
-	size_t size = t->nfit_size;
 	struct acpi_nfit_system_address *spa;
 	struct acpi_nfit_control_region *dcr;
 	struct acpi_nfit_data_region *bdw;
 	struct acpi_nfit_flush_address *flush;
 	unsigned int offset;
 
-	nfit_test_init_header(nfit_buf, size);
-
 	/*
 	 * spa0 (interleave first half of dimm0 and dimm1, note storage
 	 * does not actually alias the related block-data-window
 	 * regions)
 	 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit);
+	spa = nfit_buf;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_PM), 16);
@@ -533,7 +516,7 @@
 	 * does not actually alias the related block-data-window
 	 * regions)
 	 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa);
+	spa = nfit_buf + sizeof(*spa);
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_PM), 16);
@@ -542,7 +525,7 @@
 	spa->length = SPA1_SIZE;
 
 	/* spa2 (dcr0) dimm0 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 2;
+	spa = nfit_buf + sizeof(*spa) * 2;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_DCR), 16);
@@ -551,7 +534,7 @@
 	spa->length = DCR_SIZE;
 
 	/* spa3 (dcr1) dimm1 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 3;
+	spa = nfit_buf + sizeof(*spa) * 3;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_DCR), 16);
@@ -560,7 +543,7 @@
 	spa->length = DCR_SIZE;
 
 	/* spa4 (dcr2) dimm2 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 4;
+	spa = nfit_buf + sizeof(*spa) * 4;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_DCR), 16);
@@ -569,7 +552,7 @@
 	spa->length = DCR_SIZE;
 
 	/* spa5 (dcr3) dimm3 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 5;
+	spa = nfit_buf + sizeof(*spa) * 5;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_DCR), 16);
@@ -578,7 +561,7 @@
 	spa->length = DCR_SIZE;
 
 	/* spa6 (bdw for dcr0) dimm0 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 6;
+	spa = nfit_buf + sizeof(*spa) * 6;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_BDW), 16);
@@ -587,7 +570,7 @@
 	spa->length = DIMM_SIZE;
 
 	/* spa7 (bdw for dcr1) dimm1 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 7;
+	spa = nfit_buf + sizeof(*spa) * 7;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_BDW), 16);
@@ -596,7 +579,7 @@
 	spa->length = DIMM_SIZE;
 
 	/* spa8 (bdw for dcr2) dimm2 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 8;
+	spa = nfit_buf + sizeof(*spa) * 8;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_BDW), 16);
@@ -605,7 +588,7 @@
 	spa->length = DIMM_SIZE;
 
 	/* spa9 (bdw for dcr3) dimm3 */
-	spa = nfit_buf + sizeof(struct acpi_table_nfit) + sizeof(*spa) * 9;
+	spa = nfit_buf + sizeof(*spa) * 9;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;
 	spa->header.length = sizeof(*spa);
 	memcpy(spa->range_guid, to_nfit_uuid(NFIT_SPA_BDW), 16);
@@ -613,7 +596,7 @@
 	spa->address = t->dimm_dma[3];
 	spa->length = DIMM_SIZE;
 
-	offset = sizeof(struct acpi_table_nfit) + sizeof(*spa) * 10;
+	offset = sizeof(*spa) * 10;
 	/* mem-region0 (spa0, dimm0) */
 	memdev = nfit_buf + offset;
 	memdev->header.type = ACPI_NFIT_TYPE_MEMORY_MAP;
@@ -1100,15 +1083,13 @@
 
 static void nfit_test1_setup(struct nfit_test *t)
 {
-	size_t size = t->nfit_size, offset;
+	size_t offset;
 	void *nfit_buf = t->nfit_buf;
 	struct acpi_nfit_memory_map *memdev;
 	struct acpi_nfit_control_region *dcr;
 	struct acpi_nfit_system_address *spa;
 
-	nfit_test_init_header(nfit_buf, size);
-
-	offset = sizeof(struct acpi_table_nfit);
+	offset = 0;
 	/* spa0 (flat range with no bdw aliasing) */
 	spa = nfit_buf + offset;
 	spa->header.type = ACPI_NFIT_TYPE_SYSTEM_ADDRESS;