mm, dax: check for pmd_none() after split_huge_pmd()

[deliverable/linux.git] / mm / mremap.c

diff --git a/mm/mremap.c b/mm/mremap.c
index d77946a997f798ecc25ccaee2886139ff9d9a587..8eeba02fc99137b5a47996750159de8a455e2c4d 100644 (file)
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -210,6 +210,8 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
                                }
                        }
                        split_huge_pmd(vma, old_pmd, old_addr);
+                       if (pmd_none(*old_pmd))
+                               continue;
                        VM_BUG_ON(pmd_trans_huge(*old_pmd));
                }
                if (pmd_none(*new_pmd) && __pte_alloc(new_vma->vm_mm, new_vma,