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

Pull libnvdimm fixes from Dan Williams:

 - Fix a crash that occurs at driver initialization if the memory region
   is already busy (request_mem_region() fails).

 - Fix a vma validation check that mistakenly allows a private device-
   dax mapping to be established. Device-dax explicitly forbids private
   mappings so it can guarantee a given fault granularity and backing
   memory type.

 Both of these fixes have soaked in -next and are tagged for -stable.

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  device-dax: fail all private mapping attempts
  device-dax: check devm_nsio_enable() return value

Author: torvalds

drivers/dax/dax.c

@@ -270,8 +270,8 @@ static int check_vma(struct dax_dev *dax_dev, struct vm_area_struct *vma,
 	if (!dax_dev->alive)
 		return -ENXIO;
 
-	/* prevent private / writable mappings from being established */
-	if ((vma->vm_flags & (VM_NORESERVE|VM_SHARED|VM_WRITE)) == VM_WRITE) {
+	/* prevent private mappings from being established */
+	if ((vma->vm_flags & VM_SHARED) != VM_SHARED) {
 		dev_info(dev, "%s: %s: fail, attempted private mapping\n",
 				current->comm, func);
 		return -EINVAL;

drivers/dax/pmem.c

@@ -78,7 +78,9 @@ static int dax_pmem_probe(struct device *dev)
 	nsio = to_nd_namespace_io(&ndns->dev);
 
 	/* parse the 'pfn' info block via ->rw_bytes */
-	devm_nsio_enable(dev, nsio);
+	rc = devm_nsio_enable(dev, nsio);
+	if (rc)
+		return rc;
 	altmap = nvdimm_setup_pfn(nd_pfn, &res, &__altmap);
 	if (IS_ERR(altmap))
 		return PTR_ERR(altmap);