From patchwork Mon Dec 13 21:51:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: andrey.konovalov@linux.dev X-Patchwork-Id: 12674633 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05D3EC433EF for ; Mon, 13 Dec 2021 21:54:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4D2206B0078; Mon, 13 Dec 2021 16:52:22 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 4817F6B007B; Mon, 13 Dec 2021 16:52:22 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 349E56B007D; Mon, 13 Dec 2021 16:52:22 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0172.hostedemail.com [216.40.44.172]) by kanga.kvack.org (Postfix) with ESMTP id 27E596B0078 for ; Mon, 13 Dec 2021 16:52:22 -0500 (EST) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E02A6181AC9C6 for ; Mon, 13 Dec 2021 21:52:11 +0000 (UTC) X-FDA: 78914119662.15.20B2D9A Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf10.hostedemail.com (Postfix) with ESMTP id 18F1FC000F for ; Mon, 13 Dec 2021 21:52:07 +0000 (UTC) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1639432330; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=C/H8xEvLFjZpRKDTHcIRqvJZF1FN7N83kytVLUev48w=; b=RU4B+gZHDI9itDnuYpC93S28E3z8WcdMO41jsEOZpHLbSu3BCce89t5cQGIPf66hKE3By4 6MqlPIKu2ZXjSiATCbbiHui1+0+YiCHmTqyWQf17JNdXLn3JItiX5754T7LomyZY/+l7Ob iOtfifAKwhwnlPviuvJL+Lk0lB7vUu0= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko , Andrew Morton Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, linux-mm@kvack.org, Vincenzo Frascino , Catalin Marinas , Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, Peter Collingbourne , Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH mm v3 03/38] kasan, page_alloc: merge kasan_free_pages into free_pages_prepare Date: Mon, 13 Dec 2021 22:51:22 +0100 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: andrey.konovalov@linux.dev Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=RU4B+gZH; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf10.hostedemail.com: domain of andrey.konovalov@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 18F1FC000F X-Stat-Signature: 9zoy3cu5j1aecoit7kj78t6jsgpjnsnp X-HE-Tag: 1639432327-151499 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Andrey Konovalov Currently, the code responsible for initializing and poisoning memory in free_pages_prepare() is scattered across two locations: kasan_free_pages() for HW_TAGS KASAN and free_pages_prepare() itself. This is confusing. This and a few following patches combine the code from these two locations. Along the way, these patches also simplify the performed checks to make them easier to follow. Replaces the only caller of kasan_free_pages() with its implementation. As kasan_has_integrated_init() is only true when CONFIG_KASAN_HW_TAGS is enabled, moving the code does no functional changes. This patch is not useful by itself but makes the simplifications in the following patches easier to follow. Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko --- Changes v2->v3: - Update patch description. --- include/linux/kasan.h | 8 -------- mm/kasan/common.c | 2 +- mm/kasan/hw_tags.c | 11 ----------- mm/page_alloc.c | 6 ++++-- 4 files changed, 5 insertions(+), 22 deletions(-) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 4a45562d8893..a8bfe9f157c9 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -96,7 +96,6 @@ static inline bool kasan_hw_tags_enabled(void) } void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags); -void kasan_free_pages(struct page *page, unsigned int order); #else /* CONFIG_KASAN_HW_TAGS */ @@ -117,13 +116,6 @@ static __always_inline void kasan_alloc_pages(struct page *page, BUILD_BUG(); } -static __always_inline void kasan_free_pages(struct page *page, - unsigned int order) -{ - /* Only available for integrated init. */ - BUILD_BUG(); -} - #endif /* CONFIG_KASAN_HW_TAGS */ static inline bool kasan_has_integrated_init(void) diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 92196562687b..a0082fad48b1 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -387,7 +387,7 @@ static inline bool ____kasan_kfree_large(void *ptr, unsigned long ip) } /* - * The object will be poisoned by kasan_free_pages() or + * The object will be poisoned by kasan_poison_pages() or * kasan_slab_free_mempool(). */ diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index 7355cb534e4f..0b8225add2e4 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -213,17 +213,6 @@ void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags) } } -void kasan_free_pages(struct page *page, unsigned int order) -{ - /* - * This condition should match the one in free_pages_prepare() in - * page_alloc.c. - */ - bool init = want_init_on_free(); - - kasan_poison_pages(page, order, init); -} - #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) void kasan_enable_tagging_sync(void) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 7c2b29483b53..740fb01a27ed 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1367,15 +1367,17 @@ static __always_inline bool free_pages_prepare(struct page *page, /* * As memory initialization might be integrated into KASAN, - * kasan_free_pages and kernel_init_free_pages must be + * KASAN poisoning and memory initialization code must be * kept together to avoid discrepancies in behavior. * * With hardware tag-based KASAN, memory tags must be set before the * page becomes unavailable via debug_pagealloc or arch_free_page. */ if (kasan_has_integrated_init()) { + bool init = want_init_on_free(); + if (!skip_kasan_poison) - kasan_free_pages(page, order); + kasan_poison_pages(page, order, init); } else { bool init = want_init_on_free();