Move prep_compound_page() before post_alloc_hook() in prep_new_page(). The next patch adds a folio_zero_user() call to post_alloc_hook(), which uses folio_nr_pages() to determine how many pages to zero. Without compound metadata set up first, folio_nr_pages() returns 1 for higher-order allocations, so only the first page would be zeroed.
All other operations in post_alloc_hook() (arch_alloc_page, KASAN, debug, page owner, etc.) use raw page pointers with explicit order counts and are unaffected by this reordering. Signed-off-by: Michael S. Tsirkin <[email protected]> Assisted-by: Claude:claude-opus-4-6 Assisted-by: cursor-agent:GPT-5.4-xhigh --- mm/page_alloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c19eaf76607c..04c03c56abec 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1895,11 +1895,11 @@ static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags unsigned int alloc_flags, unsigned long user_addr) { - post_alloc_hook(page, order, gfp_flags, user_addr); - if (order && (gfp_flags & __GFP_COMP)) prep_compound_page(page, order); + post_alloc_hook(page, order, gfp_flags, user_addr); + /* * page is set pfmemalloc when ALLOC_NO_WATERMARKS was necessary to * allocate the page. The expectation is that the caller is taking -- MST
