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[217.140.101.70]) by mx.google.com with ESMTP id y16si2679549ejo.172.2019.05.29.05.12.35 for ; Wed, 29 May 2019 05:12:36 -0700 (PDT) Received-SPF: pass (google.com: domain of catalin.marinas@arm.com designates 217.140.101.70 as permitted sender) client-ip=217.140.101.70; Authentication-Results: mx.google.com; spf=pass (google.com: domain of catalin.marinas@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=catalin.marinas@arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DDBEE80D; Wed, 29 May 2019 05:12:34 -0700 (PDT) Received: from mbp (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9733C3F59C; Wed, 29 May 2019 05:12:28 -0700 (PDT) Date: Wed, 29 May 2019 13:12:25 +0100 From: Catalin Marinas To: Christoph Hellwig Cc: Andrey Konovalov , Kees Cook , 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 Subject: Re: [PATCH v15 00/17] arm64: untag user pointers passed to the kernel Message-ID: <20190529121225.q2zjgurxqnohvmkg@mbp> References: <20190521182932.sm4vxweuwo5ermyd@mbp> <201905211633.6C0BF0C2@keescook> <6049844a-65f5-f513-5b58-7141588fef2b@oracle.com> <20190523201105.oifkksus4rzcwqt4@mbp> <20190524101139.36yre4af22bkvatx@mbp> <20190529061126.GA18124@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190529061126.GA18124@infradead.org> User-Agent: NeoMutt/20170113 (1.7.2) 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: On Tue, May 28, 2019 at 11:11:26PM -0700, Christoph Hellwig wrote: > On Tue, May 28, 2019 at 04:14:45PM +0200, Andrey Konovalov wrote: > > 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? > > It absolutely needs to move to common code. Having arch code leads > to pointless (often unintentional) semantic difference between > architectures, and lots of boilerplate code. That's fine by me as long as we agree on the semantics (which shouldn't be hard; Khalid already following up). We should probably also move the proposed ABI document [1] into a common place (or part of since we'll have arm64-specifics like prctl() calls to explicitly opt in to memory tagging). [1] https://lore.kernel.org/lkml/20190318163533.26838-1-vincenzo.frascino@arm.com/T/#u -- Catalin