diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index a3b2871..1f4ec7b 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -140,17 +140,15 @@
 #endif
 
 /*
- * When walking page tables, get the address of the next boundary, or
- * the end address of the range if that comes earlier.  Although end might
- * wrap to 0 only in clear_page_range, __boundary may wrap to 0 throughout.
+ * When walking page tables, get the address of the next boundary,
+ * or the end address of the range if that comes earlier.  Although no
+ * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
  */
 
-#ifndef pgd_addr_end
 #define pgd_addr_end(addr, end)						\
 ({	unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK;	\
 	(__boundary - 1 < (end) - 1)? __boundary: (end);		\
 })
-#endif
 
 #ifndef pud_addr_end
 #define pud_addr_end(addr, end)						\