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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 07C68C606AF for ; Mon, 8 Jul 2019 13:35:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D796E20656 for ; Mon, 8 Jul 2019 13:35:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731354AbfGHNfj (ORCPT ); Mon, 8 Jul 2019 09:35:39 -0400 Received: from mga18.intel.com ([134.134.136.126]:8716 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728797AbfGHNfi (ORCPT ); Mon, 8 Jul 2019 09:35:38 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Jul 2019 06:35:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,466,1557212400"; d="scan'208";a="364235112" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.145]) by fmsmga006.fm.intel.com with ESMTP; 08 Jul 2019 06:35:35 -0700 Received: from andy by smile with local (Exim 4.92) (envelope-from ) id 1hkTnq-0005c1-GY; Mon, 08 Jul 2019 16:35:34 +0300 Date: Mon, 8 Jul 2019 16:35:34 +0300 From: Andy Shevchenko To: Petr Mladek Cc: Geert Uytterhoeven , Miguel Ojeda Sandonis , Andrew Morton , Mans Rullgard , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/2] auxdisplay: charlcd: Deduplicate simple_strtoul() Message-ID: <20190708133534.GO9224@smile.fi.intel.com> References: <20190704115532.15679-1-andriy.shevchenko@linux.intel.com> <20190704115532.15679-2-andriy.shevchenko@linux.intel.com> <20190708131652.s3gdoieixgyekued@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190708131652.s3gdoieixgyekued@pathway.suse.cz> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo 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 Mon, Jul 08, 2019 at 03:16:52PM +0200, Petr Mladek wrote: > On Thu 2019-07-04 14:55:32, Andy Shevchenko wrote: > > Like in the commit > > 8b2303de399f ("serial: core: Fix handling of options after MMIO address") > > we may use simple_strtoul() which in comparison to kstrtoul() can do conversion > > in-place without additional and unnecessary code to be written. > > > > Signed-off-by: Andy Shevchenko > > --- > > - no change since v2 > > drivers/auxdisplay/charlcd.c | 34 +++++++--------------------------- > > 1 file changed, 7 insertions(+), 27 deletions(-) > > > > diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c > > index 92745efefb54..3858dc7a4154 100644 > > --- a/drivers/auxdisplay/charlcd.c > > +++ b/drivers/auxdisplay/charlcd.c > > @@ -287,31 +287,6 @@ static int charlcd_init_display(struct charlcd *lcd) > > return 0; > > } > > > > -/* > > - * Parses an unsigned integer from a string, until a non-digit character > > - * is found. The empty string is not accepted. No overflow checks are done. > > - * > > - * Returns whether the parsing was successful. Only in that case > > - * the output parameters are written to. > > - * > > - * TODO: If the kernel adds an inplace version of kstrtoul(), this function > > - * could be easily replaced by that. > > - */ > > -static bool parse_n(const char *s, unsigned long *res, const char **next_s) > > -{ > > - if (!isdigit(*s)) > > - return false; > > - > > - *res = 0; > > - while (isdigit(*s)) { > > - *res = *res * 10 + (*s - '0'); > > - ++s; > > - } > > - > > - *next_s = s; > > - return true; > > -} > > - > > /* > > * Parses a movement command of the form "(.*);", where the group can be > > * any number of subcommands of the form "(x|y)[0-9]+". > > @@ -336,6 +311,7 @@ static bool parse_xy(const char *s, unsigned long *x, unsigned long *y) > > { > > unsigned long new_x = *x; > > unsigned long new_y = *y; > > + char *p; > > > > for (;;) { > > if (!*s) > > @@ -345,11 +321,15 @@ static bool parse_xy(const char *s, unsigned long *x, unsigned long *y) > > break; > > > > if (*s == 'x') { > > - if (!parse_n(s + 1, &new_x, &s)) > > + new_x = simple_strtoul(s + 1, &p, 10); > > simple_strtoul() tries to detect the base even when it has been > explicitely specified. I can't see it from the code. Can you point out to this drastic bug that has to be fixed? > I am afraid that it might cause some > regressions. > > For example, the following input is strange but it is valid: > > x0x10; new code would return (16, ) instead of (10, ) > x010; new code would return (8, ) instead of (10, ) > > Best Regards, > Petr -- With Best Regards, Andy Shevchenko