From patchwork Mon Jan 24 18:02:10 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: 12722651 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 611C8C4332F for ; Mon, 24 Jan 2022 18:03:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B57066B00A3; Mon, 24 Jan 2022 13:02:59 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B065A6B00AB; Mon, 24 Jan 2022 13:02:59 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 980416B00AC; Mon, 24 Jan 2022 13:02:59 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0160.hostedemail.com [216.40.44.160]) by kanga.kvack.org (Postfix) with ESMTP id 814266B00A3 for ; Mon, 24 Jan 2022 13:02:59 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 2403B8248D52 for ; Mon, 24 Jan 2022 18:02:59 +0000 (UTC) X-FDA: 79065951678.23.D3D01CA Received: from out0.migadu.com (out0.migadu.com [94.23.1.103]) by imf19.hostedemail.com (Postfix) with ESMTP id 9C23B1A0090 for ; Mon, 24 Jan 2022 18:02:58 +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=1643047375; 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=NtjC8GJtWhPCzF1O+E8r8kpeY3QxluInaVM8vIRb3RM=; b=bKBbSy6fPym/MRrA09RJIXkFlYKAWKOMZ3FKz5LNI3x7DUkJ4ipRMk3eZQPDdGKQEIJ+Rn j3caDMhxpDJoFvlu8+abP1Q+12iYW+9yQZ9ALHbERTjD13CazkPOVr1esNMbanQHMt1ZYL /Tgi6BMH04tWMfhdG1YeU09jhv3m/Vc= 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 02/39] kasan, page_alloc: move tag_clear_highpage out of kernel_init_free_pages Date: Mon, 24 Jan 2022 19:02:10 +0100 Message-Id: <7719874e68b23902629c7cf19f966c4fd5f57979.1643047180.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=bKBbSy6f; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf19.hostedemail.com: domain of andrey.konovalov@linux.dev designates 94.23.1.103 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev X-Stat-Signature: gun51ap6bqejznbua6tywshfg7kxr18i X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 9C23B1A0090 X-HE-Tag: 1643047378-773640 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, kernel_init_free_pages() serves two purposes: it either only zeroes memory or zeroes both memory and memory tags via a different code path. As this function has only two callers, each using only one code path, this behaviour is confusing. Pull the code that zeroes both memory and tags out of kernel_init_free_pages(). As a result of this change, the code in free_pages_prepare() starts to look complicated, but this is improved in the few following patches. Those improvements are not integrated into this patch to make diffs easier to read. This patch does no functional changes. Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko --- Changes v2->v3: - Update patch description. --- mm/page_alloc.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 25d4f9ad3525..012170b1c47a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1282,16 +1282,10 @@ static inline bool should_skip_kasan_poison(struct page *page, fpi_t fpi_flags) PageSkipKASanPoison(page); } -static void kernel_init_free_pages(struct page *page, int numpages, bool zero_tags) +static void kernel_init_free_pages(struct page *page, int numpages) { int i; - if (zero_tags) { - for (i = 0; i < numpages; i++) - tag_clear_highpage(page + i); - return; - } - /* s390's use of memset() could override KASAN redzones. */ kasan_disable_current(); for (i = 0; i < numpages; i++) { @@ -1387,7 +1381,7 @@ static __always_inline bool free_pages_prepare(struct page *page, bool init = want_init_on_free(); if (init) - kernel_init_free_pages(page, 1 << order, false); + kernel_init_free_pages(page, 1 << order); if (!skip_kasan_poison) kasan_poison_pages(page, order, init); } @@ -2430,9 +2424,17 @@ inline void post_alloc_hook(struct page *page, unsigned int order, bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags); kasan_unpoison_pages(page, order, init); - if (init) - kernel_init_free_pages(page, 1 << order, - gfp_flags & __GFP_ZEROTAGS); + + if (init) { + if (gfp_flags & __GFP_ZEROTAGS) { + int i; + + for (i = 0; i < 1 << order; i++) + tag_clear_highpage(page + i); + } else { + kernel_init_free_pages(page, 1 << order); + } + } } set_page_owner(page, order, gfp_flags);