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[209.85.220.65]) by mx.google.com with SMTPS id j16sor9688413pgl.59.2019.05.28.07.14.58 for (Google Transport Security); Tue, 28 May 2019 07:14:58 -0700 (PDT) Received-SPF: pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=tL4iRhDx; spf=pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andreyknvl@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com 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-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" 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: 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?