1 files changed, 11 insertions, 8 deletions

diff --git a/kernel/mm/hugetlb.c b/kernel/mm/hugetlb.c
index 271e44327..8c4c1f9f9 100644
--- a/kernel/mm/hugetlb.c
+++ b/kernel/mm/hugetlb.c
@@ -40,6 +40,11 @@ int hugepages_treat_as_movable;
 int hugetlb_max_hstate __read_mostly;
 unsigned int default_hstate_idx;
 struct hstate hstates[HUGE_MAX_HSTATE];
+/*
+ * Minimum page order among possible hugepage sizes, set to a proper value
+ * at boot time.
+ */
+static unsigned int minimum_order __read_mostly = UINT_MAX;
 
 __initdata LIST_HEAD(huge_boot_pages);
 
@@ -1188,19 +1193,13 @@ static void dissolve_free_huge_page(struct page *page)
  */
 void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn)
 {
-	unsigned int order = 8 * sizeof(void *);
 	unsigned long pfn;
-	struct hstate *h;
 
 	if (!hugepages_supported())
 		return;
 
-	/* Set scan step to minimum hugepage size */
-	for_each_hstate(h)
-		if (order > huge_page_order(h))
-			order = huge_page_order(h);
-	VM_BUG_ON(!IS_ALIGNED(start_pfn, 1 << order));
-	for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << order)
+	VM_BUG_ON(!IS_ALIGNED(start_pfn, 1 << minimum_order));
+	for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << minimum_order)
 		dissolve_free_huge_page(pfn_to_page(pfn));
 }
 
@@ -1627,10 +1626,14 @@ static void __init hugetlb_init_hstates(void)
 	struct hstate *h;
 
 	for_each_hstate(h) {
+		if (minimum_order > huge_page_order(h))
+			minimum_order = huge_page_order(h);
+
 		/* oversize hugepages were init'ed in early boot */
 		if (!hstate_is_gigantic(h))
 			hugetlb_hstate_alloc_pages(h);
 	}
+	VM_BUG_ON(minimum_order == UINT_MAX);
 }
 
 static char * __init memfmt(char *buf, unsigned long n)