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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 171B0C43218 for ; Sat, 27 Apr 2019 21:04:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6E3E2077B for ; Sat, 27 Apr 2019 21:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726488AbfD0VEH (ORCPT ); Sat, 27 Apr 2019 17:04:07 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:57356 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726088AbfD0VEH (ORCPT ); Sat, 27 Apr 2019 17:04:07 -0400 Received: from localhost (unknown [12.154.31.190]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 9F97614CF438B; Sat, 27 Apr 2019 14:04:05 -0700 (PDT) Date: Sat, 27 Apr 2019 17:04:02 -0400 (EDT) Message-Id: <20190427.170402.1871506886672225679.davem@davemloft.net> To: mkubecek@suse.cz Cc: netdev@vger.kernel.org, dsahern@gmail.com, johannes.berg@intel.com, jiri@mellanox.com, pablo@netfilter.org, kadlec@blackhole.kfki.hu, fw@strlen.de, netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next 0/3] make nla_nest_start() add NLA_F_NESTED flag From: David Miller In-Reply-To: References: X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sat, 27 Apr 2019 14:04:06 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Kubecek Date: Fri, 26 Apr 2019 11:13:03 +0200 (CEST) > One of the comments in recent review of the ethtool netlink series pointed > out that proposed ethnl_nest_start() helper which adds NLA_F_NESTED to > second argument of nla_nest_start() is not really specific to ethtool > netlink code. That is hard to argue with as closer inspection revealed that > exactly the same helper already exists in ipset code (except it's a macro > rather than an inline function). > > Another observation was that even if NLA_F_NESTED flag was introduced in > 2007, only few netlink based interfaces set it in kernel generated messages > and even many recently added APIs omit it. That is unfortunate as without > the flag, message parsers not familiar with attribute semantics cannot > recognize nested attributes and do not see message structure; this affects > e.g. wireshark dissector or mnl_nlmsg_fprintf() from libmnl. > > This is why I'm suggesting to rename existing nla_nest_start() to different > name (nla_nest_start_noflag) and reintroduce nla_nest_start() as a wrapper > adding NLA_F_NESTED flag. This is implemented in first patch which is > mostly generated by spatch. Second patch drops ipset helper macros which > lose their purpose. Third patch cleans up minor coding style issues found > by checkpatch.pl in first patch. > > We could leave nla_nest_start() untouched and simply add a wrapper adding > NLA_F_NESTED but that would probably preserve the state when even most new > code doesn't set the flag. Series applied, thank you.