From b8491b9052fef036aac0ca3afc18ef223aef6f61 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Thu, 24 Mar 2022 18:10:28 -0700 Subject: [PATCH] kasan, page_alloc: refactor init checks in post_alloc_hook Separate code for zeroing memory from the code clearing tags in post_alloc_hook(). This patch is not useful by itself but makes the simplifications in the following patches easier to follow. This patch does no functional changes. Link: https://lkml.kernel.org/r/2283fde963adfd8a2b29a92066f106cc16661a3c.1643047180.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Acked-by: Marco Elver Cc: Andrey Ryabinin Cc: Catalin Marinas Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Mark Rutland Cc: Peter Collingbourne Cc: Vincenzo Frascino Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 94a220d661b1..d2d6e48d2d83 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2368,19 +2368,21 @@ inline void post_alloc_hook(struct page *page, unsigned int order, kasan_alloc_pages(page, order, gfp_flags); } else { bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags); + bool init_tags = init && (gfp_flags & __GFP_ZEROTAGS); kasan_unpoison_pages(page, order, init); - if (init) { - if (gfp_flags & __GFP_ZEROTAGS) { - int i; + if (init_tags) { + int i; - for (i = 0; i < 1 << order; i++) - tag_clear_highpage(page + i); - } else { - kernel_init_free_pages(page, 1 << order); - } + for (i = 0; i < 1 << order; i++) + tag_clear_highpage(page + i); + + init = false; } + + if (init) + kernel_init_free_pages(page, 1 << order); } set_page_owner(page, order, gfp_flags);