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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_2 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 04D57C433DF for ; Fri, 21 Aug 2020 02:45:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD47C20758 for ; Fri, 21 Aug 2020 02:45:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727118AbgHUCpD (ORCPT ); Thu, 20 Aug 2020 22:45:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:53294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726840AbgHUCpC (ORCPT ); Thu, 20 Aug 2020 22:45:02 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0D94B20758; Fri, 21 Aug 2020 02:45:00 +0000 (UTC) Date: Thu, 20 Aug 2020 22:44:59 -0400 From: Steven Rostedt To: Joe Perches Cc: Nicolas Boichat , Mauro Carvalho Chehab , Greg Kroah-Hartman , Andy Shevchenko , Sakari Ailus , devel@driverdev.osuosl.org, lkml , Linux Media Mailing List , Peter Zijlstra , Thomas Gleixner , Josh Poimboeuf , Douglas Anderson , Guenter Roeck Subject: Re: [PATCH v4 3/3] media: atomisp: Only use trace_printk if allowed Message-ID: <20200820224459.0968b9f4@oasis.local.home> In-Reply-To: References: <20200820170951.v4.1.Ia54fe801f246a0b0aee36fb1f3bfb0922a8842b0@changeid> <20200820170951.v4.3.I066d89f39023956c47fb0a42edf196b3950ffbf7@changeid> <20200820102347.15d2f610@oasis.local.home> <20200820203601.4f70bf98@oasis.local.home> <20200820215701.667f02b2@oasis.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 20 Aug 2020 19:36:19 -0700 Joe Perches wrote: > On Thu, 2020-08-20 at 21:57 -0400, Steven Rostedt wrote: > > On Fri, 21 Aug 2020 09:39:19 +0800 > > Nicolas Boichat wrote: > [] > > > Some other approaches/ideas: > > > 1. Filter all lkml messages that contain trace_printk. Already found > > > 1 instance, and I can easily reply to those with a semi-canned answer, > > > if I remember to check that filter regularly (not sustainable in the > > > long run...). > > > > Added Joe Perches to the thread. > > > > We can update checkpatch.pl to complain about a trace_printk() that it > > finds in the added code. > > Why? > > I don't see much value in a trace_printk checkpatch warning. > tracing is still dependent on CONFIG_TRACING otherwise > trace_printk is an if (0) > > ELI5 please. > Because no production code should contain trace_printk(). It should be deleted before going to Linus. If you have trace_printk() in your code, you will be greeted by the following banner in your dmesg: ********************************************************** ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** ** ** ** trace_printk() being used. Allocating extra memory. ** ** ** ** This means that this is a DEBUG kernel and it is ** ** unsafe for production use. ** ** ** ** If you see this message and you are not debugging ** ** the kernel, report this immediately to your vendor! ** ** ** ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** ********************************************************** -- Steve