Return-path: Received: from mail-qa0-f47.google.com ([209.85.216.47]:65262 "EHLO mail-qa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753976AbaFIKWW (ORCPT ); Mon, 9 Jun 2014 06:22:22 -0400 Received: by mail-qa0-f47.google.com with SMTP id s7so7549193qap.20 for ; Mon, 09 Jun 2014 03:22:21 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <53956986.8070603@openwrt.org> References: <1399624824-9204-1-git-send-email-janusz.dziedzic@tieto.com> <20140520142453.GB13981@tuxdriver.com> <20140520180832.GD13981@tuxdriver.com> <1400610273.4474.6.camel@jlt4.sipsolutions.net> <1400688233.4136.8.camel@jlt4.sipsolutions.net> <53956986.8070603@openwrt.org> Date: Mon, 9 Jun 2014 12:22:21 +0200 Message-ID: (sfid-20140609_122232_111047_1C3D9064) Subject: Re: [PATCH] wireless-regdb: add DFS CAC time parameter From: Janusz Dziedzic To: Felix Fietkau Cc: Johannes Berg , "Luis R. Rodriguez" , "John W. Linville" , "wireless-regdb@lists.infradead.org" , linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 9 June 2014 10:00, Felix Fietkau wrote: > On 2014-05-21 18:03, Johannes Berg wrote: >> On Tue, 2014-05-20 at 11:48 -0700, Luis R. Rodriguez wrote: >> >>> > I think we should, but if we can't then at least can we cut to an >>> > extensible format? >> >> I don't see any way to extend the format right now. >> >> There's a wrinkle with making it more extensible too though - if we do >> that then we must be extremely careful that future older crda versions >> (i.e. the next version that we're about to write) will not parse a newer >> extended file more permissively, so our extensions are limited anyway. >> >> Looks like the format update really is needed, which probably means we >> should change the scripts to generate two databases and change the >> filename, or so? > How about making the format properly extensible by reusing what we're > already doing to keep the kernel ABI stable? For example, we could store > the database in a netlink-like attribute format, with some changes to > make it fixed endian. > I'm already doing just that for a few things in OpenWrt, so I have > working C code for writing and parsing such a format. > > Another nice feature would be to indicate in the attributes if crda is > required to understand them, or if it can just continue with a warning. > > If done right, I think we can probably make this the last time we change > the format version. > What kind of benefit we have having binary format between crda <-> wireless-regd (nl-based or current regulatory.bin)? This is additional code/work to do - why we need that? BR Janusz