Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:60064 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756128AbdDGTez (ORCPT ); Fri, 7 Apr 2017 15:34:55 -0400 Date: Fri, 07 Apr 2017 12:34:53 -0700 (PDT) Message-Id: <20170407.123453.846031355373739122.davem@davemloft.net> (sfid-20170407_213627_704477_06C2D28B) To: pablo@netfilter.org Cc: johannes@sipsolutions.net, linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [RFC 0/3] netlink: extended error reporting From: David Miller In-Reply-To: <20170407192714.GA23349@salvia> References: <1491592185.5800.7.camel@sipsolutions.net> <20170407.122223.385211483743191711.davem@davemloft.net> <20170407192714.GA23349@salvia> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Pablo Neira Ayuso Date: Fri, 7 Apr 2017 21:27:14 +0200 > On Fri, Apr 07, 2017 at 12:22:23PM -0700, David Miller wrote: >> From: Johannes Berg >> Date: Fri, 07 Apr 2017 21:09:45 +0200 >> >> > On Fri, 2017-04-07 at 21:06 +0200, Pablo Neira Ayuso wrote: >> >> On Fri, Apr 07, 2017 at 08:59:12PM +0200, Johannes Berg wrote: >> >> [...] >> >> > Heh. I think I really want to solve - at least partially - >> >> > nla_parse() >> >> > to see that it can be done this way. It'd be nice to even transform >> >> > all >> >> > the callers (I generated half of these patches with spatch anyway) >> >> > to >> >> > have at least that. >> >> >> >> We can just have a modified version of nla_parse that deals with >> >> this. >> > >> > Yes, but we need to figure out a good way to have the offset. >> > >> > We also need to see if we want to *force* having the offset. In some >> > sense that'd be useful, in another it might be very complicated to fill >> > it in at all times, if for example errors come from lower layers like >> > drivers. >> >> It has to be optional, some kinds of errors don't have an exact >> context per-se. >> >> Also another way to look at this is that we're providing a lot of >> new power and expressability. So even if only one aspect of the >> new error reporting is used it's a positive step forward. >> >> So allow offset "0" meaning "unspecified". > > Instead, we can just not send the offset attribute to userspace if > it's not specified. So missing attribute means "unspecified". Agreed, not providing the attribute to indicate this is fine.