From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 19 Oct 2016 10:58:28 +0200 (CEST) Received: from mail-wm0-f68.google.com ([74.125.82.68]:36459 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23991970AbcJSI6WVt91v (ORCPT ); Wed, 19 Oct 2016 10:58:22 +0200 Received: by mail-wm0-f68.google.com with SMTP id o81so2926442wma.3 for ; Wed, 19 Oct 2016 01:58:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=na1xEiY7vwFkk2mtwTzhXScjGg35mMtciEEQOBLT21o=; b=oE0LfCjOczjTxKOPIZR1tCsr+UwAOD+Bljms1i16ebPzHiLEWudOeIv8R3N6SoVhc7 XZkonaBh9jWN3FGOqi6YDDGFJm9dWKgJ4rxFjLNIh9VbBcg3QGOuD4Vadq/g9oOP/ATV etreg9sppNuydFDMlkF+iqoUp48N4xJcC2bnULoJ73/aV2DDoNPTha9Tw/ZoAeok7Fak yzLShRtclzvuV5Cfip2UgoOQOe3CdosDE9Beyi+dC9ORuEpndvY2UXQMJGNwy/IEEeeC 4P9W3JKHhFyyXZuMuVTb2mq1O2+gr2VKMWtcpQVLdfAp6Mt7i5Y/LiHSulLN4YGldEPk PavA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=na1xEiY7vwFkk2mtwTzhXScjGg35mMtciEEQOBLT21o=; b=ME8BI2v/uIXWZLQ1VmEXTEbcEapuv/17JJc8RUIWDpbAmiPu+RcXusU906uuebXERt whaaBUfWte6cb10YTptIODq2PPphaLS4a0ag24jIgUudrJIj3zv8nnIt6izLyHHXQK+1 EYMUaibNbIZM0j5eA5AqhTJUZ9BlvvScyM2uCL58ZchfSbRR5uHeVYzJsQ0XmRlF8FnU smXJHIDcTnQrNhPhSqfqjUWDE8nPaLUuc6RP3OcSTg9DZ8aniUiq1HvHiV8wGkN1uHZ4 Kd/MIuqvH3mSGGWShd+9d/6FEX3+riG9QHTBfiDrNOf9ldC8/cDQb8f2YDhyU1OvUBWh IExw== X-Gm-Message-State: AA6/9RkZ2V7IiI2WbySikf3ae9m9efHyesx9n/1c7KLu1RBke/94ucm9R9758nGBiPL8tA== X-Received: by 10.28.98.67 with SMTP id w64mr1725706wmb.50.1476867497041; Wed, 19 Oct 2016 01:58:17 -0700 (PDT) Received: from localhost (cpc94060-newt37-2-0-cust185.19-3.cable.virginm.net. [92.234.204.186]) by smtp.gmail.com with ESMTPSA id wn5sm25840301wjb.42.2016.10.19.01.58.15 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 19 Oct 2016 01:58:15 -0700 (PDT) Date: Wed, 19 Oct 2016 09:58:15 +0100 From: Lorenzo Stoakes To: Michal Hocko Cc: linux-mm@kvack.org, Linus Torvalds , Jan Kara , Hugh Dickins , Dave Hansen , Rik van Riel , Mel Gorman , Andrew Morton , adi-buildroot-devel@lists.sourceforge.net, ceph-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, kvm@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cris-kernel@axis.com, linux-fbdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mips@linux-mips.org, linux-rdma@vger.kernel.org, linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-sh@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly pass FOLL_* flags Message-ID: <20161019085815.GA22239@lucifer> References: <20161013002020.3062-1-lstoakes@gmail.com> <20161018153050.GC13117@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161018153050.GC13117@dhcp22.suse.cz> User-Agent: Mutt/1.7.1 (2016-10-04) Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 55504 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: lstoakes@gmail.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On Tue, Oct 18, 2016 at 05:30:50PM +0200, Michal Hocko wrote: > I am wondering whether we can go further. E.g. it is not really clear to > me whether we need an explicit FOLL_REMOTE when we can in fact check > mm != current->mm and imply that. Maybe there are some contexts which > wouldn't work, I haven't checked. This flag is set even when /proc/self/mem is used. I've not looked deeply into this flag but perhaps accessing your own memory this way can be considered 'remote' since you're not accessing it directly. On the other hand, perhaps this is just mistaken in this case? > I guess there is more work in that area and I do not want to impose all > that work on you, but I couldn't resist once I saw you playing in that > area ;) Definitely a good start! Thanks, I am more than happy to go as far down this rabbit hole as is helpful, no imposition at all :)