From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753407AbbDBNRd (ORCPT ); Thu, 2 Apr 2015 09:17:33 -0400 Received: from cantor2.suse.de ([195.135.220.15]:45987 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753356AbbDBNR2 (ORCPT ); Thu, 2 Apr 2015 09:17:28 -0400 Subject: Re: [PATCH 00/86] pci: export pci_ids.h and related cleanups From: Jean Delvare To: "Michael S. Tsirkin" Cc: Christoph Hellwig , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Bjorn Helgaas , Dave Jones , Jesse Barnes In-Reply-To: <20150402131850-mutt-send-email-mst@redhat.com> References: <1427635734-24786-1-git-send-email-mst@redhat.com> <20150402094424.0de6c990@endymion.delvare> <20150402094608-mutt-send-email-mst@redhat.com> <20150402082306.GA24610@infradead.org> <1427965456.4063.1272.camel@chaos.site> <20150402120711-mutt-send-email-mst@redhat.com> <1427973330.4063.1410.camel@chaos.site> <20150402131850-mutt-send-email-mst@redhat.com> Content-Type: text/plain; charset="UTF-8" Organization: Suse Linux Date: Thu, 02 Apr 2015 15:17:25 +0200 Message-ID: <1427980645.4281.78.camel@chaos.site> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le Thursday 02 April 2015 à 14:05 +0200, Michael S. Tsirkin a écrit : > On Thu, Apr 02, 2015 at 01:15:30PM +0200, Jean Delvare wrote: > > Le Thursday 02 April 2015 à 12:09 +0200, Michael S. Tsirkin a écrit : > > > On Thu, Apr 02, 2015 at 11:04:16AM +0200, Jean Delvare wrote: > > > > Le Thursday 02 April 2015 à 01:23 -0700, Christoph Hellwig a écrit : > > > > > The class ids are a hardware defintion, not a kernel API. Just use the > > > > > definitions from libpci, or copy over the kernel header if you prefer > > > > > it over the libpci definutions. > > > > > > > > I agree with Christoph, such defines would better come from > > > > pciutils-devel, not the kernel. > > > > > > This just leads to code duplication. Projects that don't link with > > > pciutils don't want to depend on it. > > > > Well, they don't have to depend on anything then, they can keep defining > > their own named IDs. > > > > Please realize that 1* code duplication is impossible to avoid > > completely and 2* this hardly qualifies as code duplication in the first > > place (giving symbolic names to constants is not actual programming.) > > If it's not actual programming, why keep arguing about it? Clam down, please. You brought it on the table, not me. I'm only trying to help. > What's the problem with exporting class IDs? Zero maintainance overhead and makes > life a bit easier to userspace. Anything that belongs to uapi implies maintenance overhead: greater care to what is being added, and impossibility to rename or remove anything. Plus, as explained before, this is conceptually wrong, these values are defined externally and are not a kernel API. You still have not explained how user-space would actually benefit from the change anyway, as previous kernels did not export that file, projects can't rely on it unless they stop supporting all kernels before v4.1. And again, just because exporting this file (or even part of it) looks convenient, doesn't mean it's right. I am under the impression that you did not read my previous explanations very carefully. That's sad because they took me a long time to write. -- Jean Delvare SUSE L3 Support