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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 1C0E3C4361B for ; Mon, 7 Dec 2020 12:57:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E1CCA23403 for ; Mon, 7 Dec 2020 12:57:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725918AbgLGM5M (ORCPT ); Mon, 7 Dec 2020 07:57:12 -0500 Received: from mga11.intel.com ([192.55.52.93]:13931 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726007AbgLGM5M (ORCPT ); Mon, 7 Dec 2020 07:57:12 -0500 IronPort-SDR: 6uIFZvBr8T7kMRWXQ0WNfDZBkXFq4XguGpKlTHCW9Ikozt1XV+D7oDaZvyC2xmDQ31vNKOzlme o5q2fmXKZZ6A== X-IronPort-AV: E=McAfee;i="6000,8403,9827"; a="170183969" X-IronPort-AV: E=Sophos;i="5.78,399,1599548400"; d="scan'208";a="170183969" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Dec 2020 04:55:26 -0800 IronPort-SDR: s70YmdCNIipXNxGDGwpZ8QETuIuy78AlYTbT3UUmyK/Scnw+b594bY7I/f8Ox7XS6WPVvgE8hp qolkEVVMK63w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.78,399,1599548400"; d="scan'208";a="407133557" Received: from cvg-ubt08.iil.intel.com (HELO [10.185.176.12]) ([10.185.176.12]) by orsmga001.jf.intel.com with ESMTP; 07 Dec 2020 04:55:19 -0800 Subject: Re: [RFC PATCH] do_exit(): panic() recursion detected To: Peter Zijlstra Cc: Jonathan Corbet , Luis Chamberlain , Kees Cook , Iurii Zaikin , "Paul E. McKenney" , Andrew Morton , Randy Dunlap , Thomas Gleixner , Mauro Carvalho Chehab , Mike Kravetz , "Guilherme G. Piccoli" , Andy Shevchenko , Kars Mulder , Lorenzo Pieralisi , Kishon Vijay Abraham I , Arvind Sankar , Joe Perches , Rafael Aquini , "Eric W. Biederman" , Christian Brauner , Alexei Starovoitov , Davidlohr Bueso , Michel Lespinasse , Jann Horn , chenqiwu , Minchan Kim , Christophe Leroy , Vladimir Kondratiev , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org References: <20201207124050.4016994-1-vladimir.kondratiev@linux.intel.com> <20201207125145.GM3040@hirez.programming.kicks-ass.net> From: Vladimir Kondratiev Message-ID: <8056f890-0297-6fa9-c9a6-c9909e0f24af@linux.intel.com> Date: Mon, 7 Dec 2020 14:55:18 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <20201207125145.GM3040@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org We do panic on oops as well. We panic on anything that may point to system stability issues. I can't proof this code can't be reached without oops, so I want to panic here as well. On 12/7/20 2:51 PM, Peter Zijlstra wrote: > On Mon, Dec 07, 2020 at 02:40:49PM +0200, Vladimir Kondratiev wrote: >> From: Vladimir Kondratiev >> >> Recursive do_exit() is symptom of compromised kernel integrity. >> For safety critical systems, it may be better to >> panic() in this case to minimize risk. > > You've not answered the previously posed question on why panic_on_oops > isn't more suitable for your type of systems. > >> Signed-off-by: Vladimir Kondratiev >> Change-Id: I42f45900a08c4282c511b05e9e6061360d07db60 > > This Change-ID crap doesn't belong in kernel patches. >