From patchwork Mon Dec 13 21:53:04 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: 12674659 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 64236C433F5 for ; Mon, 13 Dec 2021 21:59:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3C0F06B008A; Mon, 13 Dec 2021 16:53:55 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 36EC56B008C; Mon, 13 Dec 2021 16:53:55 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 25E846B0092; Mon, 13 Dec 2021 16:53:55 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay036.a.hostedemail.com [64.99.140.36]) by kanga.kvack.org (Postfix) with ESMTP id 176376B008A for ; Mon, 13 Dec 2021 16:53:55 -0500 (EST) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay12.hostedemail.com (Postfix) with ESMTP id DEA161202F3 for ; Mon, 13 Dec 2021 21:53:44 +0000 (UTC) X-FDA: 78914123568.02.F574604 Received: from out0.migadu.com (out0.migadu.com [94.23.1.103]) by imf27.hostedemail.com (Postfix) with ESMTP id 2F5AA4000F for ; Mon, 13 Dec 2021 21:53:43 +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=1639432423; 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=dOh19dmutFQ/pltDwA8i5MQc8W9IDJ9Ae5wPaYnC3pU=; b=VSO7sqm1jjWyMMDWhMaR1rdySEHaYPvb+RyXr6cKmDPxvaGBQ9enVh48nGsxTarQq8mvN3 suj/SUIbhdRrMFD9ajfBZFTP7dN/CSoX7fHYhQs/1tQHc2zrjTCS2aK9h6Ij2tQZRnbwGe u13o2rRFO4BXg2eHeiZ7j6zUKBQJPKs= 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 14/38] kasan, page_alloc: simplify kasan_unpoison_pages call site Date: Mon, 13 Dec 2021 22:53:04 +0100 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: andrey.konovalov@linux.dev X-Stat-Signature: jq73arywjrdgfxwyns1epeookqtf8ga6 Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=VSO7sqm1; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf27.hostedemail.com: domain of andrey.konovalov@linux.dev designates 94.23.1.103 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 2F5AA4000F X-HE-Tag: 1639432423-806766 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 90a2f353d230..497db24ed169 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2433,15 +2433,18 @@ 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)