alpha: handle pgtable_page_ctor() fail

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/alpha/include/asm/pgalloc.h

@@ -72,7 +72,10 @@ pte_alloc_one(struct mm_struct *mm, unsigned long address)
 	if (!pte)
 		return NULL;
 	page = virt_to_page(pte);
-	pgtable_page_ctor(page);
+	if (!pgtable_page_ctor(page)) {
+		__free_page(page);
+		return NULL;
+	}
 	return page;
 }