From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Lendacky Subject: Re: [PATCH net-next 6/6] amd-xgbe: Resolve checkpatch warning about sscanf usage Date: Wed, 25 Jun 2014 08:27:38 -0500 Message-ID: <53AACE4A.6090601@amd.com> References: <20140624211900.20681.46554.stgit@tlendack-t1.amdoffice.net> <20140624211935.20681.85586.stgit@tlendack-t1.amdoffice.net> <1403647225.29061.64.camel@joe-AO725> <53A9FF42.2090502@amd.com> <1403650410.11163.2.camel@joe-AO725> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Cc: , To: Joe Perches Return-path: Received: from mail-bl2lp0204.outbound.protection.outlook.com ([207.46.163.204]:40753 "EHLO na01-bl2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753576AbaFYN2B (ORCPT ); Wed, 25 Jun 2014 09:28:01 -0400 In-Reply-To: <1403650410.11163.2.camel@joe-AO725> Sender: netdev-owner@vger.kernel.org List-ID: On 06/24/2014 05:53 PM, Joe Perches wrote: > On Tue, 2014-06-24 at 17:44 -0500, Tom Lendacky wrote: >> On 06/24/2014 05:00 PM, Joe Perches wrote: >>> On Tue, 2014-06-24 at 16:19 -0500, Tom Lendacky wrote: >>>> Checkpatch issued a warning preferring to use kstrto when >>>> using a single variable sscanf. Change the sscanf invocation to >>>> a kstrtouint call. >>> [] >>>> diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-debugfs.c b/drivers/net/ethernet/amd/xgbe/xgbe-debugfs.c >>> [] >>>> @@ -165,10 +165,9 @@ static ssize_t xgbe_common_write(const char __user *buffer, size_t count, >>>> return len; >>>> >>>> workarea[len] = '\0'; >>>> - if (sscanf(workarea, "%x", &scan_value) == 1) >>>> - *value = scan_value; >>>> - else >>>> - return -EIO; >>>> + ret = kstrtouint(workarea, 0, value); >>> >>> Don't you need to use 16 for the base here? > >> Using 0 allows for greater flexibility in the input format. > > True, but there could be a change in behavior like reading a > previously hex value like 10 is now a decimal 10 not decimal 16. > >>> Are there any issues with any of the various callers >>> getting a different error return? >>> >>> -EINVAL/-ERANGE vs -EIO ? >> There shouldn't be, but I can always return -EIO to be >> consistent with how it was previously. > > Up to you Tom. I just wanted you to think about it. > Understood. This is a brand new driver that is still being developed so I have some latitude initially on what and how I make changes. I understand that later I'll have to maintain behaviors, interfaces, etc. Thanks, Tom > cheers, Joe >