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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 981F0ECAAD3 for ; Wed, 14 Sep 2022 09:36:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230315AbiINJgR (ORCPT ); Wed, 14 Sep 2022 05:36:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230453AbiINJf3 (ORCPT ); Wed, 14 Sep 2022 05:35:29 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8BF7122283; Wed, 14 Sep 2022 02:32:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1663147973; x=1694683973; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=3COSI+5DkvURhmR3kwSxTX5q54q4f1aW8pTt8mxl1hY=; b=QbpF0XiVEpGt6wM31Gn6pf+mThe2GKABohY1BC8j0S+9MCgulV3uTGeb fNN75dMaFSMS+NIVCT2RyQaZIYlNYDHwJiamW5H4XjLsGAx+wDSLzjA5S yNS37dIIGE92d4auLSd7lURdcZlIc8Dd3p3fb2pyKvoYebc2KPUh1mrA0 A+FAl/tl8C/2e4vvOrp0qiCyrvi4uYs62YOZD8EeTyBjMdWK9pqSVQK7u 1JgO9GG+DgLNmSAoWfb1qxEGH0cT94Khkjqj5and9auhwu5s1BjW2jNjl soRNhTkOXlytZaTZHCwSFMH2rDkdxv+SwaxO2w+JU2a7AZJs8oCccM7HZ g==; X-IronPort-AV: E=McAfee;i="6500,9779,10469"; a="384676471" X-IronPort-AV: E=Sophos;i="5.93,315,1654585200"; d="scan'208";a="384676471" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2022 02:32:53 -0700 X-IronPort-AV: E=Sophos;i="5.93,315,1654585200"; d="scan'208";a="720521087" Received: from smile.fi.intel.com ([10.237.72.54]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2022 02:32:50 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.96) (envelope-from ) id 1oYOlD-0028WF-2H; Wed, 14 Sep 2022 12:32:47 +0300 Date: Wed, 14 Sep 2022 12:32:47 +0300 From: Andy Shevchenko To: "Farber, Eliav" Cc: jdelvare@suse.com, linux@roeck-us.net, robh+dt@kernel.org, p.zabel@pengutronix.de, rtanwar@maxlinear.com, linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, hhhawa@amazon.com, jonnyc@amazon.com Subject: Re: [PATCH v5 20/21] hwmon: (mr75203) add debugfs to read and write temperature coefficients Message-ID: References: <20220908152449.35457-1-farbere@amazon.com> <20220908152449.35457-21-farbere@amazon.com> <581a4a0b-8e0e-b7a2-f873-77ed74b54e96@amazon.com> <3b121ab4-dd64-68b3-ee89-8571b5d3651e@amazon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 14, 2022 at 07:26:36AM +0300, Farber, Eliav wrote: > On 9/13/2022 8:01 PM, Andy Shevchenko wrote: > > On Tue, Sep 13, 2022 at 05:40:16PM +0300, Farber, Eliav wrote: > > > On 9/13/2022 4:06 PM, Farber, Eliav wrote: ... > > > It seems like debugfs_attr_write() calls simple_attr_write() and it uses > > > kstrtoull(), which is why it fails when setting a negative value. > > > This is the same also in v6.0-rc5. > > > > > > debugfs_attr_read() on the other hand does show the correct value also > > > when j is negative. > > > > Which puzzles me since there is a few drivers that use %lld. > > Yeah, changing it to > > > >        ret = sscanf(attr->set_buf, attr->fmt, &val); > >        if (ret != 1) > >                ret = -EINVAL; > > > > probably can fix that. Dunno if debugfs maintainer is okay with this. > > > > P.S. This needs revisiting all format strings to see if there are no > > additional > > characters, otherwise that needs to be addressed first, if feasible. > > I was thinking of making such a correction: > > -       ret = kstrtoull(attr->set_buf, 0, &val); > +       if (attr->set_buf[0] == '-') > +               ret = kstrtoll(attr->set_buf, 0, &val); > +       else > +               ret = kstrtoull(attr->set_buf, 0, &val); > > and when I tested the change it worked, but then I noticed this commit: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/libfs.c?h=v6.0-rc5&id=488dac0c9237647e9b8f788b6a342595bfa40bda > > According to this, it previously used simple_strtoll() which supports > negative values, but was changed to use kstrtoull() to deliberately > return '-EINVAL' if it gets a negative value. > > So I’m not sure debugfs maintainers will be okay with a fix that > basically reverts the commit I mentioned. > Hence, what do you suggest to do with my commit? > Is it ok to leave it as it is today? Meanwhile asking is not a problem, at least we will know for sure. And yes, leave it as is, but point to the thread where you asking the clarification. -- With Best Regards, Andy Shevchenko