From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753901AbaIPVnb (ORCPT ); Tue, 16 Sep 2014 17:43:31 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:43367 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753837AbaIPVn3 (ORCPT ); Tue, 16 Sep 2014 17:43:29 -0400 Date: Tue, 16 Sep 2014 14:43:34 -0700 From: Darren Hart To: Frans Klaver Cc: Greg Kroah-Hartman , Corentin Chary , Rafael Wysocki , acpi4asus-user , platform-driver-x86 , linux-kernel@vger.kernel.org, linux-acpi , "H. Peter Anvin" Subject: Re: [PATCH 10/13] eeepc-laptop: compare proper return values in get_cpufv Message-ID: <20140916214334.GC6856@vmdeb7> References: <1410563212-31565-1-git-send-email-fransklaver@gmail.com> <1410563212-31565-11-git-send-email-fransklaver@gmail.com> <20140915214902.GB64909@vmdeb7> <20140915215125.GA21435@kroah.com> <20140915215527.GC7867@gmail.com> <20140916205247.GA6856@vmdeb7> <20140916212715.GB6856@vmdeb7> <20140916214037.GB23674@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140916214037.GB23674@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 16, 2014 at 11:40:37PM +0200, Frans Klaver wrote: > On Tue, Sep 16, 2014 at 02:27:15PM -0700, Darren Hart wrote: > > > > - When reading and writing sysfs device attribute files, avoid dependency > > on specific error codes wherever possible. This minimizes coupling to > > the error handling implemementation within the kernel. > > > > In general, failures to read or write sysfs device attributes shall > > propogate errors wherever possible. Common errors include, but are not > > limited to: > > > > -EIO: The read or store operation is not supported, typically returned by > > the sysfs system itself if the read or store pointer is NULL. > > > > -ENXIO: The read or store operation failed > > > > Error codes will not be changed without good reason, and should a change > > to error codes result in user-space breakage, it will be fixed, or the > > the offending change will be reverted. > > sysfs-rules.txt is written for user space? In that case, reverting the > change is as much a fix as patching it. > > > > > Userspace applications can, however, expect the format and contents of > > the attribute files to remain consistent in the absence of a version > > attribute change in the context of a given attributes. Agreed, but I wanted to make this clear to kernel devs reading this as well, rather than duplicating this blurb elsewhere. > > ...attribute. > > That's it for the nit-picking. Thanks for the plural catch. I'll send to Greg as a patch. -- Darren Hart Intel Open Source Technology Center