From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755483AbbFLXrA (ORCPT ); Fri, 12 Jun 2015 19:47:00 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36619 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755443AbbFLXq5 (ORCPT ); Fri, 12 Jun 2015 19:46:57 -0400 Date: Fri, 12 Jun 2015 16:46:56 -0700 From: Greg KH To: One Thousand Gnomes Cc: devel@driverdev.osuosl.org, hamohammed.sa@gmail.com, tapaswenipathak@gmail.com, linux-kernel@vger.kernel.org, hsweeten@visionengravers.com, abbotti@mev.co.uk, julien.dehee@gmail.com, viro@zeniv.linux.org.uk Subject: Re: [PATCH] staging: comedi: replace ENOSYS by proper error codes Message-ID: <20150612234656.GB11536@kroah.com> References: <1434140438-57879-1-git-send-email-julien.dehee@gmail.com> <20150612204327.GB1410@kroah.com> <20150612220616.14fdd5b7@lxorguk.ukuu.org.uk> <20150612222626.GA10514@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150612222626.GA10514@kroah.com> User-Agent: Mutt/1.5.23+89 (0255b37be491) (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 12, 2015 at 03:26:26PM -0700, Greg KH wrote: > On Fri, Jun 12, 2015 at 10:06:16PM +0100, One Thousand Gnomes wrote: > > On Fri, 12 Jun 2015 13:43:27 -0700 > > Greg KH wrote: > > > > > On Fri, Jun 12, 2015 at 10:20:38PM +0200, julien.dehee@gmail.com wrote: > > > > From: Julien Dehee > > > > > > > > comedi/comedi_fops.c > > > > use ENODEV following open manual > > > > That should probably be ENXIO by a strict reading, but Linux has always > > used ENODEV 8) > > > > > > > > > > comedi/drivers.c > > > > use ENOTTY following ioctl manual > > > > > > > > drivers/serial2002.c > > > > use ENOTTY following ioctl manual > > > > > > What do you mean by "ioctl manual"? > > > > man 2 ioctl > > > > Unknown ioctls on a device should error with ENOTTY. It's one of > > those crazy pieces of Unix history. > > Note that the man 2 ioctl interface is not always what the kernel > exposes, but rather, what your libc exposes to other programs. So > setting these kernel values might not change what you get all the way > through, have you tested it? We also have the issue of the existing userspace comedi code, I don't know if it's handling the ioctl errors differently than ioctl(2) says, but that should be checked as well before I can take this patch. thanks, greg k-h