From: Zi Yan <ziy@nvidia.com>

mem_map is only guaranteed to be virtually contiguous within a section.
Use PAGES_PER_SECTION to check the condition properly.

Signed-off-by: Zi Yan <ziy@nvidia.com>
Cc: Mike Kravetz <redacted>
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
---
 mm/hugetlb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ce79d76c42ce..7f78203d6feb 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c

@@ -1784,7 +1784,7 @@ pgoff_t hugetlb_basepage_index(struct page *page)
 	pgoff_t index = page_index(page_head);
 	unsigned long compound_idx;
 
-	if (compound_order(page_head) >= MAX_ORDER)
+	if (compound_order(page_head) >= PAGES_PER_SECTION)
 		compound_idx = page_to_pfn(page) - page_to_pfn(page_head);
 	else
 		compound_idx = page - page_head;

-- 
2.30.2