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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 ED4CCC433E7 for ; Fri, 16 Oct 2020 02:48:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A113D208C7 for ; Fri, 16 Oct 2020 02:48:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816535; bh=rLlJSTd/jaZP9BY5EqjGjcK1DFidff+fwX7ncfrLHRg=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=IzLYfDczHJ7ZD90scQWT5jYXCpJaIChnt/F+RlayZyHlv5pu3Xk6yu2xGxTMnWowK D3p4dWhnif+/hzpj8LUWeL84W/sIdPSkgf7D6xwCYJjo9neK7XpH9J0W9+iBGlRCnw 0tr0LkrV8lwEvKtB2NdWOu0Rz/G05V7v7tuagld0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404377AbgJPCsz (ORCPT ); Thu, 15 Oct 2020 22:48:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:36598 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404364AbgJPCsz (ORCPT ); Thu, 15 Oct 2020 22:48:55 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 EE8C120897; Fri, 16 Oct 2020 02:48:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816534; bh=rLlJSTd/jaZP9BY5EqjGjcK1DFidff+fwX7ncfrLHRg=; h=Date:From:To:Subject:In-Reply-To:From; b=fXeaFRRx8zhLrFdqW3dBFDtIBaChMulWCAo4gZK2xeh7JBC+inwxv4Ts4nCWxypsE 0OMGstwxKQT+VhfQsLLkR6+MQiZNhVDjvDlYr6zlBOeKYC7oft57FRD166+NDskLjC a10sCvFrQTdccRyb5/fBlt8nAsN5dQCMgnD97nyM= Date: Thu, 15 Oct 2020 19:48:53 -0700 From: Andrew Morton To: akpm@linux-foundation.org, drinkcat@chromium.org, joe@perches.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, rostedt@goodmis.org, torvalds@linux-foundation.org Subject: [patch 125/156] checkpatch: warn if trace_printk and friends are called Message-ID: <20201016024853.NXTjAZOIJ%akpm@linux-foundation.org> In-Reply-To: <20201015192732.f448da14e9854c7cb7299956@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Nicolas Boichat Subject: checkpatch: warn if trace_printk and friends are called trace_printk is meant as a debugging tool, and should not be compiled into production code without specific debug Kconfig options enabled, or source code changes, as indicated by the warning that shows up on boot if any trace_printk is called: ** 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. ** Let's warn developers when they try to submit such a change. Link: https://lkml.kernel.org/r/20200825193600.v2.1.I723c43c155f02f726c97501be77984f1e6bb740a@changeid Signed-off-by: Nicolas Boichat Cc: Steven Rostedt Cc: Joe Perches Signed-off-by: Andrew Morton --- scripts/checkpatch.pl | 6 ++++++ 1 file changed, 6 insertions(+) --- a/scripts/checkpatch.pl~checkpatch-warn-if-trace_printk-and-friends-are-called +++ a/scripts/checkpatch.pl @@ -4274,6 +4274,12 @@ sub process { "Prefer dev_$level(... to dev_printk(KERN_$orig, ...\n" . $herecurr); } +# trace_printk should not be used in production code. + if ($line =~ /\b(trace_printk|trace_puts|ftrace_vprintk)\s*\(/) { + WARN("TRACE_PRINTK", + "Do not use $1() in production code (this can be ignored if built only with a debug config option)\n" . $herecurr); + } + # ENOSYS means "bad syscall nr" and nothing else. This will have a small # number of false positives, but assembly files are not checked, so at # least the arch entry code will not trigger this warning. _