[PATCH 2/6] mm/hugetlb: add same zone check in pfn_range_valid_gigantic()

[js1304]

From: Joonsoo Kim <iamjoonsoo....@lge.com>

alloc_gigantic_page() uses alloc_contig_range() and this
requires that requested range is in a single zone. To satisfy
that requirement, add this check to pfn_range_valid_gigantic().

Signed-off-by: Joonsoo Kim <iamjoonsoo....@lge.com>
---
 mm/hugetlb.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 06058ea..daceeb5 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1030,8 +1030,8 @@ static int __alloc_gigantic_page(unsigned long start_pfn,
        return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
 }
 
-static bool pfn_range_valid_gigantic(unsigned long start_pfn,
-                               unsigned long nr_pages)
+static bool pfn_range_valid_gigantic(struct zone *z,
+                       unsigned long start_pfn, unsigned long nr_pages)
 {
        unsigned long i, end_pfn = start_pfn + nr_pages;
        struct page *page;
@@ -1042,6 +1042,9 @@ static bool pfn_range_valid_gigantic(unsigned long 
start_pfn,
 
                page = pfn_to_page(i);
 
+               if (page_zone(page) != z)
+                       return false;
+
                if (PageReserved(page))
                        return false;
 
@@ -1074,7 +1077,7 @@ static struct page *alloc_gigantic_page(int nid, unsigned 
int order)
 
                pfn = ALIGN(z->zone_start_pfn, nr_pages);
                while (zone_spans_last_pfn(z, pfn, nr_pages)) {
-                       if (pfn_range_valid_gigantic(pfn, nr_pages)) {
+                       if (pfn_range_valid_gigantic(z, pfn, nr_pages)) {
                                /*
                                 * We release the zone lock here because
                                 * alloc_contig_range() will also lock the zone
-- 
1.9.1