From nobody Tue Apr 7 16:28:42 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D2D9ECAAD5 for ; Fri, 26 Aug 2022 15:14:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344318AbiHZPOP (ORCPT ); Fri, 26 Aug 2022 11:14:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245408AbiHZPMg (ORCPT ); Fri, 26 Aug 2022 11:12:36 -0400 Received: from mail-ed1-x549.google.com (mail-ed1-x549.google.com [IPv6:2a00:1450:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EDE9DF080 for ; Fri, 26 Aug 2022 08:09:36 -0700 (PDT) Received: by mail-ed1-x549.google.com with SMTP id s3-20020a056402520300b00446f5068565so1236480edd.7 for ; Fri, 26 Aug 2022 08:09:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc; bh=ThlNJAw9Kex8KZrskRhHj0vt2sXcunlblCUmHxCmdH0=; b=qQ2U4pH+aEHV3VhL/BG61D7fD+fTTCboEipAha6RdIlQZwkpHT+D6S+zluEN3z1B+q p6KSrVqARRa5621nYeg6EZduZRldgx+r7wiEO2xx4Q1xdyk3NHKRP+n4BtOU+EkTRiBv n9pYohc41L9MNpZ4FFw1iKeBekfif+vSNYJKYp9IPK+WdwoL5Xq+pRz96l2kWYetAuz9 ItAJhGyVh4AlEUo/NPut7UEgT36U97b+onPRJ1+xwb33JHHm9d1XBCaLKaZdeHB78F1o GDrzwrmR2heq2RM/Ijy6NFuNEoHEGLQn9rAcq11k6RQRmGERKya5Rzxx6la0Wnscwu1/ yKKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc; bh=ThlNJAw9Kex8KZrskRhHj0vt2sXcunlblCUmHxCmdH0=; b=z3FJPUTAR37Bl0Vi9mScDSh3tu2+iFxD0E5Tks0nAujW8XYuinksn7IjDFzJIdiC2Y ev62G2iWck8Eu/qXJHX6GsrY7YgnBNaJojPviJRobOlQHdoRbISMYCJbDRJElMO66vGW 9VLvG6VX3AGk6fALtvWDtAu5r6YgnIApF3LMGkbuv3qFV+FPUWlXZ4W8HOZcucO9uh3w l/906bM/IDrtRifIYyESP+hd34+3/HsQ6ycdteQ7pH8DoU9/w+q3iZSLWNCryxvY+hgr b9EgcrvsT4aY6XklUY4fSxY0kp7POTbyCNlwpBDfts08vNEnVQLXMY2Iu4HH34kVSzAd ogRg== X-Gm-Message-State: ACgBeo2ffdAwdw5vjUi5zeovcaA3fr8YpLSLgGPsdpl4gHuYR4UdU7XV VNf6/Ry9IU/ucGH0bQMvHS0ArNxSFs4= X-Google-Smtp-Source: AA6agR7P1+orY1RNadpoV0ZNi4BGK9MvXVRSI3uWf43JN88nANc9J/bmowMSnW9dE0hDywQIYKYvs/S52Ck= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:5207:ac36:fdd3:502d]) (user=glider job=sendgmr) by 2002:a17:906:9b16:b0:73d:af6f:746e with SMTP id eo22-20020a1709069b1600b0073daf6f746emr5932849ejc.32.1661526573448; Fri, 26 Aug 2022 08:09:33 -0700 (PDT) Date: Fri, 26 Aug 2022 17:07:52 +0200 In-Reply-To: <20220826150807.723137-1-glider@google.com> Mime-Version: 1.0 References: <20220826150807.723137-1-glider@google.com> X-Mailer: git-send-email 2.37.2.672.g94769d06f0-goog Message-ID: <20220826150807.723137-30-glider@google.com> Subject: [PATCH v5 29/44] block: kmsan: skip bio block merging logic for KMSAN From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Alexei Starovoitov , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Biggers Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" KMSAN doesn't allow treating adjacent memory pages as such, if they were allocated by different alloc_pages() calls. The block layer however does so: adjacent pages end up being used together. To prevent this, make page_is_mergeable() return false under KMSAN. Suggested-by: Eric Biggers Signed-off-by: Alexander Potapenko --- v4: -- swap block: and kmsan: in the subject v5: -- address Marco Elver's comments Link: https://linux-review.googlesource.com/id/Ie29cc2464c70032347c32ab2a22= e1e7a0b37b905 --- block/bio.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/bio.c b/block/bio.c index 3d3a2678fea25..106ef14f28c2a 100644 --- a/block/bio.c +++ b/block/bio.c @@ -869,6 +869,8 @@ static inline bool page_is_mergeable(const struct bio_v= ec *bv, *same_page =3D ((vec_end_addr & PAGE_MASK) =3D=3D page_addr); if (*same_page) return true; + else if (IS_ENABLED(CONFIG_KMSAN)) + return false; return (bv->bv_page + bv_end / PAGE_SIZE) =3D=3D (page + off / PAGE_SIZE); } =20 --=20 2.37.2.672.g94769d06f0-goog