From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.8 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1, USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40DEAC433DB for ; Fri, 12 Mar 2021 10:53:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16B2665021 for ; Fri, 12 Mar 2021 10:53:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233603AbhCLKwl (ORCPT ); Fri, 12 Mar 2021 05:52:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233595AbhCLKwW (ORCPT ); Fri, 12 Mar 2021 05:52:22 -0500 Received: from mail-wm1-x331.google.com (mail-wm1-x331.google.com [IPv6:2a00:1450:4864:20::331]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD2A4C061574 for ; Fri, 12 Mar 2021 02:52:21 -0800 (PST) Received: by mail-wm1-x331.google.com with SMTP id u5-20020a7bcb050000b029010e9316b9d5so11948403wmj.2 for ; Fri, 12 Mar 2021 02:52:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=5vl4TnJGbtOwZE1EsiegxeOEN6L8oOxqwuScwUDj6dw=; b=fdpaSkr1MOEWfiUyvbv5xMFNqGFf4I2dukUFszolGvjm1yJErXnQTeE9yRZWU0O7uN mihLs85hFyE+nAdkRPBCowkTb5sEyeJRfTSCmblsUcuF+wgKF2jg4CCmAdl/Ya/MyXqE i2YJfKCHU1fwmgFf4Smz6EsKyMQSqV0J5VzLJYzbOMSjANWOHa5lpS2q76ul/z4cNnZA YAdw70p2z9K4+GnaSyNkXRtxrKvsGaDjeDUbrDmU/C1s7tMJgYGCPTXFwavPfdWbPVsg HXzZKM9KB/4pVB1DFfxgAc6n2+yCrLxNEST6GXBOmLxCDbT2dSypZoW1pRMOwG/zu6ve 194w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=5vl4TnJGbtOwZE1EsiegxeOEN6L8oOxqwuScwUDj6dw=; b=Whv0W0M2kYFFzz/P+oDMYGQzRYTBrjs05zbF6mfRqp6fM6P5mTYAzNQrndQtrcYluy HbRUY/ZzEVEMFkjalqcJUV34R55juqyWjOLQIcWPBTpo5Kkxx/ps8WwhySdgTmxow+l+ FyXldd+4FZMX+7fn3B75SgmSKsk4IcGQr9G/uXgs5pikHVbbrOKuvYKafUy1M3mFo6Zg W60nPsq+9y5c5Z8BpkeDAQ0M5Na5Zt1CuUtigL/mtYxM7mTXsQIWcAHZBI9cutqybGUq 0m+48B/qiWXStxIujqPHXyBzuUFK6mIThmDy0jCumqt23ws2kvFE5CgQy/JC1S3iWk/S VcQA== X-Gm-Message-State: AOAM531nX9i1aQFo8MhKLahGz7XxZU1oek0Td5azbAA57M9RnEclgEwZ BmKgnGbD/dwFoBCMeky1GoNfNA== X-Google-Smtp-Source: ABdhPJxy/RG5RLN5uL47bfpYouV02imhS7sb6oHrolh4iMAPNn5VNyvy2A/C9N1x+WhCFKpcRrErMQ== X-Received: by 2002:a05:600c:214d:: with SMTP id v13mr12602188wml.162.1615546340506; Fri, 12 Mar 2021 02:52:20 -0800 (PST) Received: from elver.google.com ([2a00:79e0:15:13:d5de:d45f:f79c:cb62]) by smtp.gmail.com with ESMTPSA id n186sm1707383wmn.22.2021.03.12.02.52.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 Mar 2021 02:52:19 -0800 (PST) Date: Fri, 12 Mar 2021 11:52:14 +0100 From: Marco Elver To: Andrey Konovalov Cc: Andrew Morton , Alexander Potapenko , Andrey Ryabinin , Dmitry Vyukov , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/11] kasan: docs: update shadow memory section Message-ID: References: <6cb4988a241f086be7e7df3eea79416a53377ade.1615498565.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6cb4988a241f086be7e7df3eea79416a53377ade.1615498565.git.andreyknvl@google.com> User-Agent: Mutt/2.0.5 (2021-01-21) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 11, 2021 at 10:37PM +0100, Andrey Konovalov wrote: [...] > -The kernel maps memory in a number of different parts of the address > -space. This poses something of a problem for KASAN, which requires > -that all addresses accessed by instrumented code have a valid shadow > -region. > - > -The range of kernel virtual addresses is large: there is not enough > -real memory to support a real shadow region for every address that > -could be accessed by the kernel. > +The kernel maps memory in several different parts of the address space. > +The range of kernel virtual addresses is large: there is not enough real > +memory to support a real shadow region for every address that could be > +accessed by the kernel. Therefore, KASAN only maps real shadow for certain > +parts of the address space. > > By default > ~~~~~~~~~~ While we're here, can we change this "By default" heading which seems wrong -- the paragraph starts with "By default, ..." as well. Perhaps "Default Behaviour"?