From 0bf2edf041dcb0b304a8dbda8c699771d5a245d2 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 1 Sep 2025 17:03:27 +0200 Subject: mm/page_alloc: reject unreasonable folio/compound page sizes in alloc_contig_range_noprof() Let's reject them early, which in turn makes folio_alloc_gigantic() reject them properly. To avoid converting from order to nr_pages, let's just add MAX_FOLIO_ORDER and calculate MAX_FOLIO_NR_PAGES based on that. While at it, let's just make the order a "const unsigned order". Link: https://lkml.kernel.org/r/20250901150359.867252-7-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Zi Yan Acked-by: SeongJae Park Reviewed-by: Wei Yang Reviewed-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Signed-off-by: Andrew Morton --- include/linux/mm.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index 00c8a54127d3..77737cbf2216 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2055,11 +2055,13 @@ static inline long folio_nr_pages(const struct folio *folio) /* Only hugetlbfs can allocate folios larger than MAX_ORDER */ #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE -#define MAX_FOLIO_NR_PAGES (1UL << PUD_ORDER) +#define MAX_FOLIO_ORDER PUD_ORDER #else -#define MAX_FOLIO_NR_PAGES MAX_ORDER_NR_PAGES +#define MAX_FOLIO_ORDER MAX_PAGE_ORDER #endif +#define MAX_FOLIO_NR_PAGES (1UL << MAX_FOLIO_ORDER) + /* * compound_nr() returns the number of pages in this potentially compound * page. compound_nr() can be called on a tail page, and is defined to -- cgit v1.2.3