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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24F4AC4332F for ; Mon, 11 Oct 2021 08:36:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0FAF260C4B for ; Mon, 11 Oct 2021 08:36:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235145AbhJKIiG (ORCPT ); Mon, 11 Oct 2021 04:38:06 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]:46190 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235010AbhJKIiF (ORCPT ); Mon, 11 Oct 2021 04:38:05 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id EA6322003E; Mon, 11 Oct 2021 08:36:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1633941364; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=FPbx2B9Llgf08l9/6ELaloI4uW3syuPUrdAfP+Y5Qqs=; b=sKasgaIoJZe6ADDnCA66rzx+jt4F4vnLrnLMwfaqfATL/9+45+7ZmuriPFRGAG6LJiyZJF kOO4/p0J6FJShwtpAujtTihW8LLk44i0X90xoz92rBoTmSsWxS6Ox2leKwc1BzT/huEcJr eCiBO1hXEuWESlUJergcr5sIKtGge44= Received: from suse.cz (unknown [10.100.201.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 070EBA3B87; Mon, 11 Oct 2021 08:36:04 +0000 (UTC) Date: Mon, 11 Oct 2021 10:36:03 +0200 From: Michal Hocko To: Kees Cook Cc: Suren Baghdasaryan , Pavel Machek , Rasmus Villemoes , David Hildenbrand , John Hubbard , Andrew Morton , Colin Cross , Sumit Semwal , Dave Hansen , Matthew Wilcox , "Kirill A . Shutemov" , Vlastimil Babka , Johannes Weiner , Jonathan Corbet , Al Viro , Randy Dunlap , Kalesh Singh , Peter Xu , rppt@kernel.org, Peter Zijlstra , Catalin Marinas , vincenzo.frascino@arm.com, Chinwen Chang =?utf-8?B?KOW8temMpuaWhyk=?= , Axel Rasmussen , Andrea Arcangeli , Jann Horn , apopple@nvidia.com, Yu Zhao , Will Deacon , fenghua.yu@intel.com, thunder.leizhen@huawei.com, Hugh Dickins , feng.tang@intel.com, Jason Gunthorpe , Roman Gushchin , Thomas Gleixner , krisman@collabora.com, Chris Hyser , Peter Collingbourne , "Eric W. Biederman" , Jens Axboe , legion@kernel.org, Rolf Eike Beer , Cyrill Gorcunov , Muchun Song , Viresh Kumar , Thomas Cedeno , sashal@kernel.org, cxfcosmos@gmail.com, LKML , linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm , kernel-team Subject: Re: [PATCH v10 3/3] mm: add anonymous vma name refcounting Message-ID: References: <92cbfe3b-f3d1-a8e1-7eb9-bab735e782f6@rasmusvillemoes.dk> <20211007101527.GA26288@duo.ucw.cz> <202110071111.DF87B4EE3@keescook> <202110081344.FE6A7A82@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202110081344.FE6A7A82@keescook> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 08-10-21 13:58:01, Kees Cook wrote: > - Strings for "anon" specifically have no required format (this is good) > it's informational like the task_struct::comm and can (roughly) > anything. There's no naming convention for memfds, AF_UNIX, etc. Why > is one needed here? That seems like a completely unreasonable > requirement. I might be misreading the justification for the feature. Patch 2 is talking about tools that need to understand memeory usage to make further actions. Also Suren was suggesting "numbering convetion" as an argument against. So can we get a clear example how is this being used actually? If this is just to be used to debug by humans than I can see an argument for human readable form. If this is, however, meant to be used by tools to make some actions then the argument for strings is much weaker. -- Michal Hocko SUSE Labs