From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id CB249A0C4D; Wed, 13 Oct 2021 04:36:17 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 9705540151; Wed, 13 Oct 2021 04:36:17 +0200 (CEST) Received: from mail-lf1-f50.google.com (mail-lf1-f50.google.com [209.85.167.50]) by mails.dpdk.org (Postfix) with ESMTP id 0E35340150; Wed, 13 Oct 2021 04:36:17 +0200 (CEST) Received: by mail-lf1-f50.google.com with SMTP id p16so5078076lfa.2; Tue, 12 Oct 2021 19:36:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=SnNub58OtISyy0aih3hJTmPVc76kk+znUcfwltSwbzY=; b=bXG0ldHqNY3IburcCqwShyOwg1dZzotCsMHwNn25bGZSlvnp/2ohAE2m+CEit/MMbD 4KMq7T1krEsFtzu1610cb+jFGVdQXKAoSjD1rEI0u6OoBwrx4SKtphjqHjV6tGxLEXdf Yxb4UKqhMeTR+HmeY8LUFj9ci6SG5NgiZ+4bV2eudE+EWPHeDTuJaDQetFAMYdjSsBuj B4VQO5HE/kiQLc7lwOsB2/q6SEroi3MwKdS19Pkn7EVhYdWjZSG64Iyev/WOOXGhbveA lt8LKUz5XicYG9d+/YrwymSFtF7OmxD8o7SgtsTpq7/yEG78GcIvQ4u+vZYncfzQCuZf /tbg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=SnNub58OtISyy0aih3hJTmPVc76kk+znUcfwltSwbzY=; b=l+ocR8y00N9vMixIxLP397Ca4T6herO2UzktwO8ZQ/QCicYr3d1sxllPqK1uaoFMWc sJ5NKA5xs+m7sFrmoQgaPUPhFD5+hTz+5bpqnFuUSMqQe5CtxaOVCrQVUhzD+9YA1baO 5UOpy6n+ls13jFAwkf7ap3TWJhVg6ufDk60mwzZtS0bjKY2wu0dYc3XaVaHUI1s/pei5 QYVINTmPIfpxiM0/A2ecCxBAQJg4LRkjpzFrMKZ6C1OOPd0bpzRnPIfEc/zJt7K+bD5P 7E7GkVXA9WLhlOq6s+VU1I1SMDvADoBgmg5D63+K0ZbpN3x7RYN7T/a9rdQI69eXH11X mL6g== X-Gm-Message-State: AOAM531GY61nrEfLphFa6sSvou53HcGNOWuvmMiX+JyJqZsgn4owdIE9 3YFE4bJfyRzmj7bgtluO1Fs= X-Google-Smtp-Source: ABdhPJzk80YOXpm3MR1fLZNUJ9lAWE3I4gfBbug4VuP2eo4b81mSkzbo0BXW8Q8NxvOjph8xmFuSqA== X-Received: by 2002:a05:6512:16a2:: with SMTP id bu34mr36608863lfb.147.1634092576527; Tue, 12 Oct 2021 19:36:16 -0700 (PDT) Received: from sovereign (broadband-37-110-65-23.ip.moscow.rt.ru. [37.110.65.23]) by smtp.gmail.com with ESMTPSA id e15sm396598lfs.35.2021.10.12.19.36.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 12 Oct 2021 19:36:16 -0700 (PDT) Date: Wed, 13 Oct 2021 05:36:15 +0300 From: Dmitry Kozlyuk To: "Peng, ZhihongX" Cc: "olivier.matz@6wind.com" , "dev@dpdk.org" , "stable@dpdk.org" Message-ID: <20211013053615.1ae63b13@sovereign> In-Reply-To: References: <20210917021502.502560-2-zhihongx.peng@intel.com> <20211008064131.369133-1-zhihongx.peng@intel.com> <20211011112558.21c68bfa@sovereign> X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH v3 1/2] lib/cmdline: release cl when cmdline exit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 2021-10-13 01:53 (UTC+0000), Peng, ZhihongX: > > -----Original Message----- > > From: Dmitry Kozlyuk > > Sent: Monday, October 11, 2021 4:26 PM > > To: Peng, ZhihongX > > Cc: olivier.matz@6wind.com; dev@dpdk.org; stable@dpdk.org > > Subject: Re: [PATCH v3 1/2] lib/cmdline: release cl when cmdline exit > > > > 2021-10-08 06:41 (UTC+0000), zhihongx.peng@intel.com: > > > From: Zhihong Peng > > > > > > Malloc cl in the cmdline_stdin_new function, so release in the > > > cmdline_stdin_exit function is logical, so that cl will not be > > > released alone. > > > > > > Fixes: af75078fece3 (first public release) > > > Cc: stable@dpdk.org > > > > As I have explained before, backporting this will introduce a double-free bug > > in user apps unless their code are fixed, so it must not be done. > > The release notes have stated that this is the only thing we can do, > and this unreasonable design should be resolved as soon as possible. > And the user apps change is very small. Stable release means stable ABI, which means that a compiled binary can use the next minor version of DPDK without recompilation. No code change is possible in this scenario. If the behavior changes such that cmdline_exit() + cmdline_free() worked before and now cmdline_free() cause double-free, this is an ABI breakage. Simply put, DPDK .so are replaced, the app restarts and crashes. Users can do nothing about that. Release notes are for developers updating their application code for the next DPDK version.