From patchwork Mon Dec 20 21:59:29 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: 12696919 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 71AC2C433F5 for ; Mon, 20 Dec 2021 22:07:08 +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=SovaK1SUVhMRwwte5Tg4itJrT5EzeCXOoCwYWjrRIXE=; b=Gk8/6gLN0jx4Xh J8tO9aBdkHOydQCU1ObDKO93Tu+/n7FhIJqfZP/XBEP/yvEdMWcQn/mjKRMF52onyLfCWjIknMSJV SqwwTMU2tQC4oweuNHbuc0XcKJwVe5fqhsTps2LwwUUuhjjeW6QQ7wuPTdj+P3L0eq/aKLek4kD1Q SGUrtXjkzVOnsctLBrQLBJm0myafJSubi1IqmL5l0yxSdLwjLL9b1QiDZ2hjdziTMMetnvwPH76kp 6bahAAFzHKiPWHa7T+z8MoNukyKfYIdrKjYFNHgipe3whC60EEw9r6y+by4bJvr5mNFX0g4+xNtS1 tZITy1nTCLhS43Rer4iA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mzQmz-004eia-1i; Mon, 20 Dec 2021 22:05:49 +0000 Received: from out1.migadu.com ([2001:41d0:2:863f::]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mzQhX-004bJk-K6 for linux-arm-kernel@lists.infradead.org; Mon, 20 Dec 2021 22:00:13 +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=1640037610; 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=MBXf/nDIJH3lBRK2HYWbLL40X7GriSLmrG5CxAxbd1w=; b=WhLbP/3oSEwJM5WqmObOt3iKnwdaRrovewVBcuGS7MAKio2R7bwpElX//w79OJgCZWto1/ 1imQ3BW3juuaP52IJw/bco1OVUREGdhdOep+x3a9lf0P+jM13/ux/GVNCeDTrjAa8bRUv0 P4R59DyHKFeRDVzs+2RF34yUzza3lyE= 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 v4 14/39] kasan, page_alloc: rework kasan_unpoison_pages call site Date: Mon, 20 Dec 2021 22:59:29 +0100 Message-Id: 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-20211220_140011_869292_D1F5C4A4 X-CRM114-Status: GOOD ( 13.82 ) 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 Rework 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 changes for post_alloc_hook(). Signed-off-by: Andrey Konovalov --- Changes v3->v4: - Make the confition checks more explicit. - Update patch description. --- mm/page_alloc.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 205884e3520b..2ef0f531e881 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2433,15 +2433,20 @@ 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_GENERIC) || + IS_ENABLED(CONFIG_KASAN_SW_TAGS) || + kasan_hw_tags_enabled() && !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)