mm/page_alloc: restrict and formalize compound_page_dtors[]
Restrict elements in compound_page_dtors[] array per NR_COMPOUND_DTORS and
explicitly position them according to enum compound_dtor_id. This
improves protection against possible misalignment between
compound_page_dtors[] and enum compound_dtor_id later on.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: http://lkml.kernel.org/r/1589795958-19317-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d95442f..045c4ae 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -302,14 +302,14 @@ const char * const migratetype_names[MIGRATE_TYPES] = {
#endif
};
-compound_page_dtor * const compound_page_dtors[] = {
- NULL,
- free_compound_page,
+compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = {
+ [NULL_COMPOUND_DTOR] = NULL,
+ [COMPOUND_PAGE_DTOR] = free_compound_page,
#ifdef CONFIG_HUGETLB_PAGE
- free_huge_page,
+ [HUGETLB_PAGE_DTOR] = free_huge_page,
#endif
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- free_transhuge_page,
+ [TRANSHUGE_PAGE_DTOR] = free_transhuge_page,
#endif
};