From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: [PATCH net-2.6] ethtool: Remove fallback to old ethtool operations for ETHTOOL_SFEATURES Date: Mon, 16 May 2011 03:45:23 +0100 Message-ID: <1305513923.19966.20.camel@localhost> References: <1305335142.2851.70.camel@bwh-desktop> <20110514103539.GA5214@rere.qmqm.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Miller , netdev@vger.kernel.org To: =?UTF-8?Q?Micha=C5=82_Miros=C5=82aw?= Return-path: Received: from exchange.solarflare.com ([216.237.3.220]:28363 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753519Ab1EPCpf convert rfc822-to-8bit (ORCPT ); Sun, 15 May 2011 22:45:35 -0400 In-Reply-To: <20110514103539.GA5214@rere.qmqm.pl> Sender: netdev-owner@vger.kernel.org List-ID: On Sat, 2011-05-14 at 12:35 +0200, Micha=C5=82 Miros=C5=82aw wrote: > On Sat, May 14, 2011 at 02:05:42AM +0100, Ben Hutchings wrote: > > ethtool_set_feature_compat() squashes the feature mask into a boole= an, > > which is not correct for ethtool_ops::set_flags. > >=20 > > We could fix this, but the fallback code for ETHTOOL_SFEATURES actu= ally > > makes things more complicated for the ethtool utility and any other > > application using the ethtool API. They will still need to fall ba= ck to > > the old offload control commands in order to support older kernel > > versions. The fallback code in the kernel adds a third possibility= for > > them to handle. So make ETHTOOL_SFEATURES fail when the driver > > implements the old offload control operations, and let userland do = the > > fallback. >=20 > BTW, the idea behind the compat code is that if ETHTOOL_[GS]FEATURES = is > available, then there should be no need to fallback to old ops. For > a userspace tool that targets only kernels >=3D 2.6.39 there's no nee= d > to care about old ops at all. Well that's not true, because those tools still have to deal with ETHTOOL_F_COMPAT. And we're supposed to have all drivers converted for 2.6.40, so the hypothetical new tool only has to wait one more release. Ben. --=20 Ben Hutchings, Senior Software Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.