From patchwork Mon Dec 6 21:43:51 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: 12659755 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 AC30DC433F5 for ; Mon, 6 Dec 2021 21:49:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A86ED6B0099; Mon, 6 Dec 2021 16:45:37 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A36AB6B009B; Mon, 6 Dec 2021 16:45:37 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8FE386B009A; Mon, 6 Dec 2021 16:45:37 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0226.hostedemail.com [216.40.44.226]) by kanga.kvack.org (Postfix) with ESMTP id 8061F6B0098 for ; Mon, 6 Dec 2021 16:45:37 -0500 (EST) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 47E1F1815BBC2 for ; Mon, 6 Dec 2021 21:45:27 +0000 (UTC) X-FDA: 78888701094.20.4FF48A9 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf24.hostedemail.com (Postfix) with ESMTP id CBDE1B0000A1 for ; Mon, 6 Dec 2021 21:45:26 +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=1638827125; 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=DzChjposR8HVqGI1LyY9RFr0jz+Wu5dx9pG+xQIWYf8=; b=ka0h1Ym03kuH5Ox8LDn59GBrR/hauweOgUKRmsGeAXiqq7096r1v2XFaibQYmWydVy7RF7 h+192nLSScSWnCv4lCj6WsXt+/TMWwpV5IX8YjAcCtNZYBRe3Rfld6BxTzM5I8aAaE4Fsc 7LJiJZ+F7Sro7zz/twsMwtqU9UTjMxY= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko , Vincenzo Frascino , Catalin Marinas , Peter Collingbourne Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Andrew Morton , linux-mm@kvack.org, Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH v2 14/34] kasan, page_alloc: simplify kasan_unpoison_pages call site Date: Mon, 6 Dec 2021 22:43:51 +0100 Message-Id: <10ba3c7a7524a912098d3b1747c0ca2e1e626ebc.1638825394.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: CBDE1B0000A1 X-Stat-Signature: r34c5b7fqo3s6fcwmermqawrmio7hmxf Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ka0h1Ym0; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf24.hostedemail.com: domain of andrey.konovalov@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev X-HE-Tag: 1638827126-114424 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 Simplify the checks around kasan_unpoison_pages() call in post_alloc_hook(). The logical condition for calling this function is: - If a software KASAN mode is enabled, we need to mark shadow memory. - Otherwise, HW_TAGS KASAN is enabled, and it only makes sense to set tags if they haven't already been cleared by tag_clear_highpage(), which is indicated by init_tags. This patch concludes the simplifications for post_alloc_hook(). Signed-off-by: Andrey Konovalov --- mm/page_alloc.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 5c346375cff9..73e6500c9767 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2419,15 +2419,18 @@ inline void post_alloc_hook(struct page *page, unsigned int order, /* Note that memory is already initialized by the loop above. */ init = false; } - if (kasan_has_integrated_init()) { - if (!init_tags) { - kasan_unpoison_pages(page, order, init); + /* + * If either a software KASAN mode is enabled, or, + * in the case of hardware tag-based KASAN, + * if memory tags have not been cleared via tag_clear_highpage(). + */ + if (!IS_ENABLED(CONFIG_KASAN_HW_TAGS) || !init_tags) { + /* Mark shadow memory or set memory tags. */ + kasan_unpoison_pages(page, order, init); - /* Note that memory is already initialized by KASAN. */ + /* Note that memory is already initialized by KASAN. */ + if (kasan_has_integrated_init()) init = false; - } - } else { - kasan_unpoison_pages(page, order, init); } /* If memory is still not initialized, do it now. */ if (init)