1 files changed, 4 insertions, 2 deletions

diff --git a/mm/memory.c b/mm/memory.c
index baa999e87cd2..d7df5babcba9 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1665,9 +1665,10 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
          * behaviour that some programs depend on. We mark the "original"
          * un-COW'ed pages by matching them up with "vma->vm_pgoff".
          */
-        if (addr == vma->vm_start && end == vma->vm_end)
+        if (addr == vma->vm_start && end == vma->vm_end) {
                 vma->vm_pgoff = pfn;
-        else if (is_cow_mapping(vma->vm_flags))
+                vma->vm_flags |= VM_PFNMAP_AT_MMAP;
+        } else if (is_cow_mapping(vma->vm_flags))
                 return -EINVAL;
 
         vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
@@ -1679,6 +1680,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
                  * needed from higher level routine calling unmap_vmas
                  */
                 vma->vm_flags &= ~(VM_IO | VM_RESERVED | VM_PFNMAP);
+                vma->vm_flags &= ~VM_PFNMAP_AT_MMAP;
                 return -EINVAL;
         }