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=-11.4 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_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 50134C433E2 for ; Wed, 9 Sep 2020 15:14:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C0EA921919 for ; Wed, 9 Sep 2020 15:13:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="OL93yWh7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C0EA921919 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 25A326B0081; Wed, 9 Sep 2020 11:13:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 231616B0092; Wed, 9 Sep 2020 11:13:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 146B0900002; Wed, 9 Sep 2020 11:13:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0036.hostedemail.com [216.40.44.36]) by kanga.kvack.org (Postfix) with ESMTP id F0B756B0081 for ; Wed, 9 Sep 2020 11:13:58 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id BD46382499A8 for ; Wed, 9 Sep 2020 15:13:58 +0000 (UTC) X-FDA: 77243868156.05.heat28_2d10585270de Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin05.hostedemail.com (Postfix) with ESMTP id 8FAFB1802DDE1 for ; Wed, 9 Sep 2020 15:13:58 +0000 (UTC) X-HE-Tag: heat28_2d10585270de X-Filterd-Recvd-Size: 4754 Received: from mail-oi1-f193.google.com (mail-oi1-f193.google.com [209.85.167.193]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Wed, 9 Sep 2020 15:13:58 +0000 (UTC) Received: by mail-oi1-f193.google.com with SMTP id i17so2676897oig.10 for ; Wed, 09 Sep 2020 08:13:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=krZf25HoLYNOs+89jtLjxVuIVVFDL/DS0/iONN95wCA=; b=OL93yWh7YYd3Kjpp++lmqusu98KBOYAUlFtscMPkxq3j+FlurgE872aMXM+jYrZLfA slVo0YeMasFlKvpatP/yG3NYkdN7G9zeOdYYDSr/jO1YA4PDmwsY3l3/g2a+UUUUk0sh N/9n/d0axxncRngDQDQ73AzQCMoaR1Qi3RTeH2s7jWwOLkvp7DY3rFzAbiSaUOkyiI0j GbFHlK7xl53jSwXJVpwDyLq1COKTawKzlznu/fwxR2F5MYpx+55Ea2pfphDixt40qy/O 4WUi+T1ptbN4Z8SKmtiSt+QhKD3pGAaSGq2pBDoVmB67cUexujsDH5uHp7kmk03dwp6Y 27qA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=krZf25HoLYNOs+89jtLjxVuIVVFDL/DS0/iONN95wCA=; b=t6xaJ7YNgPFFOoF+bgl7ayZ3TtQa/4N0tou4oJGeHJANk1yGqY88MDyMgySvTzeq5I FwM8rPFYqjjBdrHp6dJ1Cb3WSRJja+DoqrrKfA8Svv/f+pro+ipP3H3mHAh5f4BqFGEQ UCtnn8WJbGCWwEq7YOMZvplLYInRhUfJI5ZR3mk1aDqlG1RgM3wL5hbd+S7hQNULN2k8 TYHKz4ynQnIe1AYV+8gbQyL7mMMyOSEeTL5lP4pvGVIwO7+Uzv2cWXfu4E/MwFKc56Oh VZmXxZ2x0c2ul4yy1ualE38LWFY70doPK5milMLd/Bq8uQ04zBg0zKJCgqLN9wUP8U/S LEPA== X-Gm-Message-State: AOAM530SCSYpB7VE3aNl2VgC5ZVNgLSrvZZLfStrpBTwIGfALh8Nm8V0 tzrqUSkcL4juQXJLtmvWmaQcniw2IDdO5LDigCRZXg== X-Google-Smtp-Source: ABdhPJxUwoCrzBiq+mXsi/+rblK6OvwTU4QXrdeC28cSOlaNtqbrVQKyBMOckNHPSlXH4EYREa5LAoQDUNJklnzlV5o= X-Received: by 2002:aca:5158:: with SMTP id f85mr992820oib.121.1599664437260; Wed, 09 Sep 2020 08:13:57 -0700 (PDT) MIME-Version: 1.0 References: <20200907134055.2878499-1-elver@google.com> <20200907134055.2878499-4-elver@google.com> In-Reply-To: <20200907134055.2878499-4-elver@google.com> From: Marco Elver Date: Wed, 9 Sep 2020 17:13:45 +0200 Message-ID: Subject: Re: [PATCH RFC 03/10] arm64, kfence: enable KFENCE for ARM64 To: Catalin Marinas , Mark Rutland , Will Deacon , Linux ARM Cc: Alexander Potapenko , Christoph Lameter , Andrew Morton , David Rientjes , Pekka Enberg , Joonsoo Kim , "H. Peter Anvin" , "Paul E. McKenney" , Andrey Konovalov , Andrey Ryabinin , Andy Lutomirski , Borislav Petkov , Dave Hansen , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Ingo Molnar , Jann Horn , Jonathan Corbet , Kees Cook , Peter Zijlstra , Qian Cai , Thomas Gleixner , "the arch/x86 maintainers" , "open list:DOCUMENTATION" , LKML , kasan-dev , Linux Memory Management List Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 8FAFB1802DDE1 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: Hello arm64 maintainers, On Mon, 7 Sep 2020 at 15:41, Marco Elver wrote: > Add architecture specific implementation details for KFENCE and enable > KFENCE for the arm64 architecture. In particular, this implements the > required interface in . Currently, the arm64 version does > not yet use a statically allocated memory pool, at the cost of a pointer > load for each is_kfence_address(). > For ARM64, we would like to solicit feedback on what the best option is > to obtain a constant address for __kfence_pool. One option is to declare > a memory range in the memory layout to be dedicated to KFENCE (like is > done for KASAN), however, it is unclear if this is the best available > option. We would like to avoid touching the memory layout. We can't yet tell what the best option for this might be. So, any suggestions on how to go about switching to a static pool would be much appreciated. Many thanks, -- Marco