From patchwork Tue Nov 30 22:05:30 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: 12648259 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 A17ECC433EF for ; Tue, 30 Nov 2021 22:06:35 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E94FC6B0075; Tue, 30 Nov 2021 17:05:44 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E1C956B0078; Tue, 30 Nov 2021 17:05:44 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C96286B007B; Tue, 30 Nov 2021 17:05:44 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0045.hostedemail.com [216.40.44.45]) by kanga.kvack.org (Postfix) with ESMTP id BA0036B0075 for ; Tue, 30 Nov 2021 17:05:44 -0500 (EST) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 7891D86E6E for ; Tue, 30 Nov 2021 22:05:34 +0000 (UTC) X-FDA: 78866978988.31.BC840CA Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf21.hostedemail.com (Postfix) with ESMTP id C9A36D0369FB for ; Tue, 30 Nov 2021 22:05:30 +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=1638309933; 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=QgrHb09Vj6aJ0+9nbQZNm9kk14SqendbAdApMN1ty98=; b=kKuuQS7/dsa+tGRFwUmdluLYwH181K80+n9qftIO6/pGTMzmQQf0P2nkonmZrMoKqotGhC 2gQtyPERQxs3yUsHIEeHisTO4bsyHx2NpZwdslj0iQ+hkkJxsH6bB5oFHsleWBfHpWH05r LRw4k8NLXCsQjuzaov4w7A1b2oPTagQ= 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 , linux-arm-kernel@lists.infradead.org, Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH 13/31] kasan, page_alloc: simplify kasan_unpoison_pages call site Date: Tue, 30 Nov 2021 23:05:30 +0100 Message-Id: <4e23fb3399fbc2bd59effeb89946a75c3c75b6a2.1638308023.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: rspam01 X-Rspamd-Queue-Id: C9A36D0369FB X-Stat-Signature: hkfmmfnszeg43bydbgrq8u5y1j8y8kr4 Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b="kKuuQS7/"; spf=pass (imf21.hostedemail.com: domain of andrey.konovalov@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev; dmarc=pass (policy=none) header.from=linux.dev X-HE-Tag: 1638309930-199237 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 ba950889f5ea..4eb341351124 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2420,15 +2420,18 @@ 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)