Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932258AbaAaA5q (ORCPT ); Thu, 30 Jan 2014 19:57:46 -0500 Received: from mail-bk0-f49.google.com ([209.85.214.49]:57813 "EHLO mail-bk0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753137AbaAaA5o (ORCPT ); Thu, 30 Jan 2014 19:57:44 -0500 MIME-Version: 1.0 X-Originating-IP: [109.128.142.46] In-Reply-To: <20140130142740.GC2185@casper.infradead.org> References: <1391087144-24490-1-git-send-email-teg@jklm.no> <20140130142740.GC2185@casper.infradead.org> From: Tom Gundersen Date: Fri, 31 Jan 2014 01:57:23 +0100 Message-ID: Subject: Re: [PATCH] rtnetlink: return the newly created link in response to newlink To: Thomas Graf Cc: netdev , LKML , John Fastabend , Nicolas Dichtel , Vlad Yasevich , Marcel Holtmann , "David S. Miller" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thomas, Thanks for your reply. On Thu, Jan 30, 2014 at 3:27 PM, Thomas Graf wrote: > On 01/30/14 at 02:05pm, Tom Gundersen wrote: >> Userspace needs to reliably know the ifindex of the netdevs it creates, >> as we cannot rely on the ifname staying unchanged. >> >> Earlier, a simlpe NLMSG_ERROR would be returned, but this returns the >> corresponding RTM_NEWLINK on success instead. > > This breaks existing Netlink applications in user space. User space > apps are not prepared to receive both a RTM_NEWLINK reply _and_ > the ACK unless they have set NLM_F_ECHO in the original request. > > You can already reliably retrieve the ifindex by listening to > RTNLGRP_LINK messages and be notified about the link created > including all follow-up renames. Ok, we'll keep doing this instead. Cheers, Tom -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/