From patchwork Mon Jan 24 18:02:18 2022 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: 12722758 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A70ADC433EF for ; Mon, 24 Jan 2022 18:39:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rE2LA4IfmoKlTPWr2wJEayJte8jAbSl6rdxKVuKehwc=; b=PpALMA+V06sBaU noDEFQ59xVsa+bY5rDTtWuftHeYQpPEpN3pKjRooa8cHs+3jBpkp0r1co/iiid0LUSDUeO7MrZmx6 l0bsSgzNYshaYHLDqvFoDGDv6V0hWGWusCaK2OFCjg006Vmd8BgUwSPLi4dTi7f4l9M6pPKlKpK9I N9IX5oj8T197blwAENUsjgeXUDD62BVN/PJ+ZwMpQk3U+O5TMgY9pHcf3hf24JjVyxSjubCVZyOtC pwUdku81091H4v2dRTEifeCdzraaOScSinzt9f9HuBi5t54oe7ycjeFhwoflktLzgmoRC/QcLR37C FZ3oN1ArVAaOfJ0FvhUg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nC4E8-004Yvc-PC; Mon, 24 Jan 2022 18:38:05 +0000 Received: from out2.migadu.com ([2001:41d0:2:aacc::]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nC3gj-004M1o-O7 for linux-arm-kernel@lists.infradead.org; Mon, 24 Jan 2022 18:03:35 +0000 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=1643047412; 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=w/5MGH+6es3Fk1qg92YmO6ftiYPgmqt9uv7fZJ7G30w=; b=Ewd4EoS+8ZT+uju28rCIama233zxxE2e5WzfxknXEwi90En1dm2WE/bMjjGE5r0FmR+9QH 3UUyPQqhW2OfcNfaOSPz/lyRJXMI2oVY3rUNZRFF1VsxNFnExD1j7T49PjemvCXbR8PbW4 5HaD1PRjMpQaRqzeh0nSlY9wy2GtTZs= From: andrey.konovalov@linux.dev To: Andrew Morton Cc: Andrey Konovalov , Marco Elver , Alexander Potapenko , 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 v6 10/39] kasan, page_alloc: merge kasan_alloc_pages into post_alloc_hook Date: Mon, 24 Jan 2022 19:02:18 +0100 Message-Id: <5ac7e0b30f5cbb177ec363ddd7878a3141289592.1643047180.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220124_100334_169129_CF857A1A X-CRM114-Status: GOOD ( 21.37 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Andrey Konovalov Currently, the code responsible for initializing and poisoning memory in post_alloc_hook() is scattered across two locations: kasan_alloc_pages() hook for HW_TAGS KASAN and post_alloc_hook() itself. This is confusing. This and a few following patches combine the code from these two locations. Along the way, these patches do a step-by-step restructure the many performed checks to make them easier to follow. Replace the only caller of kasan_alloc_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. Also move init and init_tags variables definitions out of kasan_has_integrated_init() clause in post_alloc_hook(), as they have the same values regardless of what the if condition evaluates to. This patch is not useful by itself but makes the simplifications in the following patches easier to follow. Signed-off-by: Andrey Konovalov --- Changes v2->v3: - Update patch description. --- include/linux/kasan.h | 9 --------- mm/kasan/common.c | 2 +- mm/kasan/hw_tags.c | 22 ---------------------- mm/page_alloc.c | 20 +++++++++++++++----- 4 files changed, 16 insertions(+), 37 deletions(-) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index a8bfe9f157c9..b88ca6b97ba3 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -95,8 +95,6 @@ static inline bool kasan_hw_tags_enabled(void) return kasan_enabled(); } -void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags); - #else /* CONFIG_KASAN_HW_TAGS */ static inline bool kasan_enabled(void) @@ -109,13 +107,6 @@ static inline bool kasan_hw_tags_enabled(void) return false; } -static __always_inline void kasan_alloc_pages(struct page *page, - unsigned int order, gfp_t flags) -{ - /* 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 a0082fad48b1..d9079ec11f31 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -538,7 +538,7 @@ void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size, return NULL; /* - * The object has already been unpoisoned by kasan_alloc_pages() for + * The object has already been unpoisoned by kasan_unpoison_pages() for * alloc_pages() or by kasan_krealloc() for krealloc(). */ diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index c643740b8599..76cf2b6229c7 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -192,28 +192,6 @@ void __init kasan_init_hw_tags(void) kasan_stack_collection_enabled() ? "on" : "off"); } -void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags) -{ - /* - * This condition should match the one in post_alloc_hook() in - * page_alloc.c. - */ - bool init = !want_init_on_free() && want_init_on_alloc(flags); - bool init_tags = init && (flags & __GFP_ZEROTAGS); - - if (flags & __GFP_SKIP_KASAN_POISON) - SetPageSkipKASanPoison(page); - - if (init_tags) { - int i; - - for (i = 0; i != 1 << order; ++i) - tag_clear_highpage(page + i); - } else { - kasan_unpoison_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 868480d463c7..abed862d889d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2398,6 +2398,9 @@ static bool check_new_pages(struct page *page, unsigned int order) inline void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags) { + bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags); + bool init_tags = init && (gfp_flags & __GFP_ZEROTAGS); + set_page_private(page, 0); set_page_refcounted(page); @@ -2413,15 +2416,22 @@ inline void post_alloc_hook(struct page *page, unsigned int order, /* * As memory initialization might be integrated into KASAN, - * kasan_alloc_pages and kernel_init_free_pages must be + * KASAN unpoisoning and memory initializion code must be * kept together to avoid discrepancies in behavior. */ if (kasan_has_integrated_init()) { - 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); + if (gfp_flags & __GFP_SKIP_KASAN_POISON) + SetPageSkipKASanPoison(page); + + if (init_tags) { + int i; + 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) {