Commit 9294b128 authored by Andrey Konovalov's avatar Andrey Konovalov Committed by Linus Torvalds
Browse files

kasan, page_alloc: combine tag_clear_highpage calls in post_alloc_hook 

Move tag_clear_highpage() loops out of the kasan_has_integrated_init()
clause as a code simplification.

This patch does no functional changes.

Link: https://lkml.kernel.org/r/587e3fc36358b88049320a89cc8dc6deaecb0cda.1643047180.git.andreyknvl@google.com


Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
Reviewed-by: default avatarAlexander Potapenko <glider@google.com>
Acked-by: default avatarMarco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b42090ae

mm/page_alloc.c

+16 −16
Original line number Diff line number Diff line
@@ -2367,29 +2367,29 @@ inline void post_alloc_hook(struct page *page, unsigned int order, 
	 * KASAN unpoisoning and memory initializion code must be

	 * kept together to avoid discrepancies in behavior.

	 */

	if (kasan_has_integrated_init()) {

		if (gfp_flags & __GFP_SKIP_KASAN_POISON)

			SetPageSkipKASanPoison(page);



	/*

	 * If memory tags should be zeroed (which happens only when memory

	 * should be initialized as well).

	 */

	if (init_tags) {

		int i;



		/* Initialize both memory and tags. */

		for (i = 0; i != 1 << order; ++i)

			tag_clear_highpage(page + i);

		} else {

			kasan_unpoison_pages(page, order, init);

		}

	} else {

		kasan_unpoison_pages(page, order, init);



		if (init_tags) {

			int i;



			for (i = 0; i < 1 << order; i++)

				tag_clear_highpage(page + i);



		/* Note that memory is already initialized by the loop above. */

		init = false;

	}

	if (kasan_has_integrated_init()) {

		if (gfp_flags & __GFP_SKIP_KASAN_POISON)

			SetPageSkipKASanPoison(page);



		if (!init_tags)

			kasan_unpoison_pages(page, order, init);

	} else {

		kasan_unpoison_pages(page, order, init);



		if (init)

			kernel_init_free_pages(page, 1 << order);