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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 C3F65C2BB84 for ; Mon, 7 Sep 2020 15:25:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7050221481 for ; Mon, 7 Sep 2020 15:25:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730153AbgIGPZ0 (ORCPT ); Mon, 7 Sep 2020 11:25:26 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:40572 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730176AbgIGPYl (ORCPT ); Mon, 7 Sep 2020 11:24:41 -0400 Received: from ip5f5af70b.dynamic.kabel-deutschland.de ([95.90.247.11] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1kFIiK-0004KC-Bk; Mon, 07 Sep 2020 15:05:48 +0000 Date: Mon, 7 Sep 2020 17:05:47 +0200 From: Christian Brauner To: Adalbert =?utf-8?B?TGF6xINy?= Cc: linux-mm@kvack.org, linux-api@vger.kernel.org, Andrew Morton , Alexander Graf , Stefan Hajnoczi , Jerome Glisse , Paolo Bonzini , Mihai =?utf-8?B?RG9uyJt1?= , Mircea Cirjaliu , Andy Lutomirski , Arnd Bergmann , Sargun Dhillon , Aleksa Sarai , Oleg Nesterov , Jann Horn , Kees Cook , Matthew Wilcox Subject: Re: [RESEND RFC PATCH 0/5] Remote mapping Message-ID: <20200907150547.hst4luvrpntdb3lr@wittgenstein> References: <20200904113116.20648-1-alazar@bitdefender.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200904113116.20648-1-alazar@bitdefender.com> Sender: linux-api-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Fri, Sep 04, 2020 at 02:31:11PM +0300, Adalbert Lazăr wrote: > This patchset adds support for the remote mapping feature. > Remote mapping, as its name suggests, is a means for transparent and > zero-copy access of a remote process' address space. > access of a remote process' address space. > > The feature was designed according to a specification suggested by > Paolo Bonzini: > >> The proposed API is a new pidfd system call, through which the parent > >> can map portions of its virtual address space into a file descriptor > >> and then pass that file descriptor to a child. > >> > >> This should be: > >> > >> - upstreamable, pidfd is the new cool thing and we could sell it as a > >> better way to do PTRACE_{PEEK,POKE}DATA In all honesty, that sentence made me a bit uneasy as it reads like this is implemented on top of pidfds because it makes it more likely to go upstream not because it is the right design. To be clear, I'm not implying any sort of malicious intent on your part but I would suggest to phrase this a little better. :)