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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 1A998C48BDF for ; Fri, 18 Jun 2021 16:56:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 04274613E9 for ; Fri, 18 Jun 2021 16:56:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235978AbhFRQ7F (ORCPT ); Fri, 18 Jun 2021 12:59:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:51816 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231601AbhFRQ7D (ORCPT ); Fri, 18 Jun 2021 12:59:03 -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 DE9AE613D1; Fri, 18 Jun 2021 16:56:52 +0000 (UTC) Date: Fri, 18 Jun 2021 12:56:51 -0400 From: Steven Rostedt To: Daniel Bristot de Oliveira Cc: Phil Auld , Sebastian Andrzej Siewior , Kate Carcia , Jonathan Corbet , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Alexandre Chartre , Clark Willaims , John Kacur , Juri Lelli , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V4 06/12] trace: Add a generic function to read/write u64 values from tracefs Message-ID: <20210618125651.7de04840@oasis.local.home> In-Reply-To: <681a2fb508b3dad2979ac705c3df633f14abb9b2.1623746916.git.bristot@redhat.com> References: <681a2fb508b3dad2979ac705c3df633f14abb9b2.1623746916.git.bristot@redhat.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 15 Jun 2021 11:28:45 +0200 Daniel Bristot de Oliveira wrote: > +static ssize_t > +trace_min_max_read(struct file *filp, char __user *ubuf, size_t cnt, > + loff_t *ppos) > +{ > + struct trace_min_max_param *param = filp->private_data; > + char buf[ULL_STR_SIZE]; > + u64 val; > + int len; White space issue above? > + > + if (!param) > + return -EFAULT; And above here too? > + > + val = *param->val; > + > + if (cnt > sizeof(buf)) > + cnt = sizeof(buf); > + > + len = snprintf(buf, sizeof(buf), "%llu\n", val); > + > + return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); Egad, this entire patch is filled with whitespace issues! Please check your other patches too. > +} > + > + > +#define ULL_STR_SIZE 22 /* 20 digits max */ Nit. I'd make this 24, just to be integer aligned. I mean, it's used as: trace_min_max_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_min_max_param *param = filp->private_data; char buf[ULL_STR_SIZE]; u64 val; int len; Probably should reverse the above as well, that way if you do have ULL_STR_SIZE as 24, then the int len, will fit right in before the u64 val. Although, I think compilers are free to optimize that too :-/ -- Steve