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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_MED,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 8C424C04AB6 for ; Tue, 28 May 2019 14:15:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E71C2081C for ; Tue, 28 May 2019 14:15:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tL4iRhDx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726802AbfE1OO7 (ORCPT ); Tue, 28 May 2019 10:14:59 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:46490 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726532AbfE1OO6 (ORCPT ); Tue, 28 May 2019 10:14:58 -0400 Received: by mail-pg1-f195.google.com with SMTP id v9so4683274pgr.13 for ; Tue, 28 May 2019 07:14:58 -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=uILrnXKlYf2xjYbSzuRjxVZ/GKBRZG6iBlNh5FVzNqg=; b=tL4iRhDxBHlVQ+tyr45nAjSTrWm4FGkpU9/gqgAOrFY5B7cJ7oOHLY740uFY6v9Apt FqrRnmxExj3iQTQYzs/PenqdbelZVqX7ImfSm34SI3kUWnaFv2Pd1vXHqDLGJYPgxvw8 7KLV8hWWHlsDJ/UwTZYLqE3rqDzmSrpBL95BUyqXducEuzu32sr8cYoLi6lrm/VHbu19 kGodX0/6n5OKGvwKCkqnvqlMkPVgQ7D246As7ltK/sqPD0kwVjhXWCNgzf39x95m1k16 0eXP9QfKOUXReSvTh9f0l8fCYrSWQokxzY+jcITzAkXcdghBa76eI6mVVXYUH34oj3Ib qnwQ== 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=uILrnXKlYf2xjYbSzuRjxVZ/GKBRZG6iBlNh5FVzNqg=; b=hbyWrOgaIilAqtBNDDSuGfY9qbALzyYa4cbb3LjBwSXd/oW6Bscxz5WO3ks9WQlU84 JaMsUraFJ30oOnl//jX25juL6zkQC6JShWDRebilbhkUyCa4PmF+bmmaWDBGl5SIBUrn wYXTsgtK1ujnOtd+MKsyBzxixNnNyWMKPqqLM3gZIHejQKv20jStFrlBhQ/6wbo0wpid tmSsUuLXJsQ84v+fb8QUFZSbpwrsHm8VmITdxase1EHKN2BJpp6bl7RhambeeP+l9JQ+ CYYLcclXWtDzCUgKWjSIfibANnaEs0YdbXnmIPOEPRtYzO8MsX94eVcNGBsRA6+ju380 mfGw== X-Gm-Message-State: APjAAAUGfI8G3myJL3wo6B4HdwJywYvkfqWlERCkqRt548byfHOK2JAe JfTt5Gg1t7xg1gw3dqOCKdiEJo2SzkydEY1rGtp+vg== X-Google-Smtp-Source: APXvYqyOX9PeZsCaqURSrIEWPGIBd1WFVQ7exVP3S114miK0Cy+gUD/uDqW5wGxUjPG0aHqJLJFWW3mMb6YG8JIQdRk= X-Received: by 2002:a65:64d9:: with SMTP id t25mr132418776pgv.130.1559052897854; Tue, 28 May 2019 07:14:57 -0700 (PDT) MIME-Version: 1.0 References: <20190517144931.GA56186@arrakis.emea.arm.com> <20190521182932.sm4vxweuwo5ermyd@mbp> <201905211633.6C0BF0C2@keescook> <6049844a-65f5-f513-5b58-7141588fef2b@oracle.com> <20190523201105.oifkksus4rzcwqt4@mbp> <20190524101139.36yre4af22bkvatx@mbp> In-Reply-To: From: Andrey Konovalov Date: Tue, 28 May 2019 16:14:45 +0200 Message-ID: Subject: Re: [PATCH v15 00/17] arm64: untag user pointers passed to the kernel To: Catalin Marinas , Kees Cook Cc: Evgenii Stepanov , Linux ARM , Linux Memory Management List , LKML , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, kvm@vger.kernel.org, "open list:KERNEL SELFTEST FRAMEWORK" , Vincenzo Frascino , Will Deacon , Mark Rutland , Andrew Morton , Greg Kroah-Hartman , Yishai Hadas , Felix Kuehling , Alexander Deucher , Christian Koenig , Mauro Carvalho Chehab , Jens Wiklander , Alex Williamson , Leon Romanovsky , Dmitry Vyukov , Kostya Serebryany , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Robin Murphy , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy , Elliott Hughes , Khalid Aziz Content-Type: text/plain; charset="UTF-8" Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Thanks for a lot of valuable input! I've read through all the replies and got somewhat lost. What are the changes I need to do to this series? 1. Should I move untagging for memory syscalls back to the generic code so other arches would make use of it as well, or should I keep the arm64 specific memory syscalls wrappers and address the comments on that patch? 2. Should I make untagging opt-in and controlled by a command line argument? 3. Should I "add Documentation/core-api/user-addresses.rst to describe proper care and handling of user space pointers with untagged_addr(), with examples based on all the cases seen so far in this series"? Which examples specifically should it cover? Is there something else?