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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C8EFFC433E0 for ; Fri, 29 May 2020 08:17:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7410208E4 for ; Fri, 29 May 2020 08:17:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725865AbgE2IRw (ORCPT ); Fri, 29 May 2020 04:17:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:57912 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725562AbgE2IRw (ORCPT ); Fri, 29 May 2020 04:17:52 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id DA554AB5C; Fri, 29 May 2020 08:17:49 +0000 (UTC) Date: Fri, 29 May 2020 10:17:48 +0200 From: Petr Mladek To: Linus Torvalds Cc: Tetsuo Handa , Andrew Morton , Linux Kernel Mailing List , Dmitry Vyukov , Ondrej Mosnacek , Sergey Senozhatsky , Steven Rostedt Subject: Re: [PATCH v2] twist: allow converting pr_devel()/pr_debug() into snprintf() Message-ID: <20200529081748.GC27273@linux-b0ei> References: <20200528065603.3596-1-penguin-kernel@I-love.SAKURA.ne.jp> <20200528110646.GC11286@linux-b0ei> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 2020-05-28 12:50:35, Linus Torvalds wrote: > On Thu, May 28, 2020 at 8:17 AM Tetsuo Handa > wrote: > > > > CONFIG_TWIST_FOR_SYZKALLER_TESTING is meant for linux-next only. > > But CONFIG_TWIST_KERNEL_BEHAVIOR is meant for Linus's tree. > > I really absolutely still detest this all. I don't see the point. The > naming is completely random (both "twist" and then options like > "TWIST_FOR_SYZKALLER_TESTING" that have no conceptual meaning. > > I still don't understand why this small set of random options couldn't > just be kernel options that get set on the command line, and that have > independent and sane and explainable behavior? Why this odd mentality > of "syzkaller is special"? I am afraid that many of them could not be normal options. They change or break some behavior that is necessary by seriously used system. > I've complained about this whole thing before. I'm getting really fed > up with this whole concept of "magic crazy config options". Just to make my role clear in this saga. I am focused on the change of pr_debug() behavior. I do _not_ believe that it is worth it. But I wanted to give fuzzer guys a chance to get some data. This is why I offered to push hacky patch into linux-next via printk tree to get fuzzers fed. Such a patch would change the behavior only for the fuzzer (with the crazy config enabled) and it would be there only for a limited time. I personally do _not_ have a good feeling about having such hacks in upstream kernel. But I do not feel in position to decide about it. I wanted to solve this question later if there would have been anything to upstream. I am _not_ going to push any twists, in the current form, upstream via printk tree. Best Regards, Petr