diff --git a/include/linux/mm.h b/include/linux/mm.h
index de32c038338751bbc155793dff7a65e369d5a996..93a46ff33dc2aacd28071a65acc005c55302d0f4 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1594,8 +1594,13 @@ static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma,
 #ifdef CONFIG_MIGRATION
 static inline bool is_pinnable_page(struct page *page)
 {
-	return !(is_zone_movable_page(page) || is_migrate_cma_page(page)) ||
-		is_zero_pfn(page_to_pfn(page));
+#ifdef CONFIG_CMA
+	int mt = get_pageblock_migratetype(page);
+
+	if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
+		return false;
+#endif
+	return !(is_zone_movable_page(page) || is_zero_pfn(page_to_pfn(page)));
 }
 #else
 static inline bool is_pinnable_page(struct page *page)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6f6e4649ac210e1596054871113f32185af96659..56b3a5d673250263798888b87eddb95a89af3291 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -482,8 +482,12 @@ unsigned long __get_pfnblock_flags_mask(const struct page *page,
 	bitidx = pfn_to_bitidx(page, pfn);
 	word_bitidx = bitidx / BITS_PER_LONG;
 	bitidx &= (BITS_PER_LONG-1);
-
-	word = bitmap[word_bitidx];
+	/*
+	 * This races, without locks, with set_pfnblock_flags_mask(). Ensure
+	 * a consistent read of the memory array, so that results, even though
+	 * racy, are not corrupted.
+	 */
+	word = READ_ONCE(bitmap[word_bitidx]);
 	return (word >> bitidx) & mask;
 }