diff --git a/mm/nommu.c b/mm/nommu.c
index 1fd0c51..9edc897a 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1813,10 +1813,13 @@
 	return NULL;
 }
 
-int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
-		unsigned long to, unsigned long size, pgprot_t prot)
+int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
+		unsigned long pfn, unsigned long size, pgprot_t prot)
 {
-	vma->vm_start = vma->vm_pgoff << PAGE_SHIFT;
+	if (addr != (pfn << PAGE_SHIFT))
+		return -EINVAL;
+
+	vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
 	return 0;
 }
 EXPORT_SYMBOL(remap_pfn_range);