From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: [RFC][net-next-2.6 PATCH 3/4] ethtool: set hard_header_len using ETH_FLAG_{TX|RX}VLAN Date: Fri, 22 Oct 2010 14:00:16 +0100 Message-ID: <1287752416.2316.2.camel@achroite.uk.solarflarecom.com> References: <20101021221004.22906.58438.stgit@jf-dev1-dcblab> <20101021221015.22906.3516.stgit@jf-dev1-dcblab> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, jesse@nicira.com To: John Fastabend Return-path: Received: from mail.solarflare.com ([216.237.3.220]:46733 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751352Ab0JVNAT (ORCPT ); Fri, 22 Oct 2010 09:00:19 -0400 In-Reply-To: <20101021221015.22906.3516.stgit@jf-dev1-dcblab> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 2010-10-21 at 15:10 -0700, John Fastabend wrote: > Toggling the vlan tx|rx hw offloads needs to set the hard_header_len > as well otherwise we end up using LL_RESERVED_SPACE incorrectly. > This results in pskb_expand_head() being used unnecessarily. > > This add a check in ethtool_op_set_flags to catch the ETH_FLAG_TXVLAN > flag and set the header length. [...] Note that not every driver that implements the set_flags operation calls back to ethtool_op_set_flags(). Ben. -- Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.