From: Pankaj Raghav Date: Fri, 5 Sep 2025 15:00:12 +0000 (+0200) Subject: huge_memory: return -EINVAL in folio split functions when THP is disabled X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=fe1a50b2e39a83f90e19bc5058ba27f92854d4c1;p=users%2Fjedix%2Flinux-maple.git huge_memory: return -EINVAL in folio split functions when THP is disabled split_huge_page_to_list_[to_order](), split_huge_page() and try_folio_split() return 0 on success and error codes on failure. When THP is disabled, these functions return 0 indicating success even though an error code should be returned as it is not possible to split a folio when THP is disabled. Make all these functions return -EINVAL to indicate failure instead of 0. As large folios depend on CONFIG_THP, issue warning as this function should not be called without a large folio. Link: https://lkml.kernel.org/r/20250905150012.93714-1-kernel@pankajraghav.com Signed-off-by: Pankaj Raghav Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202509051753.riCeG7LC-lkp@intel.com/ Acked-by: David Hildenbrand Acked-by: Zi Yan Acked-by: Kiryl Shutsemau Reviewed-by: Lorenzo Stoakes Reviewed-by: Barry Song Reviewed-by: Anshuman Khandual Signed-off-by: Andrew Morton --- diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 29ef70022da1..f327d62fc985 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -588,22 +588,26 @@ static inline int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, unsigned int new_order) { - return 0; + VM_WARN_ON_ONCE_PAGE(1, page); + return -EINVAL; } static inline int split_huge_page(struct page *page) { - return 0; + VM_WARN_ON_ONCE_PAGE(1, page); + return -EINVAL; } static inline int split_folio_to_list(struct folio *folio, struct list_head *list) { - return 0; + VM_WARN_ON_ONCE_FOLIO(1, folio); + return -EINVAL; } static inline int try_folio_split(struct folio *folio, struct page *page, struct list_head *list) { - return 0; + VM_WARN_ON_ONCE_FOLIO(1, folio); + return -EINVAL; } static inline void deferred_split_folio(struct folio *folio, bool partially_mapped) {}