From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Templeman, Chaim" Subject: RE: [Intel-wired-lan] [PATCH] e1000e: Cleanup handling of VLAN_HLEN as a part of max frame size Date: Mon, 13 Apr 2015 18:26:46 +0000 Message-ID: References: <20150408204630.4643.37880.stgit@ahduyck-vm-fedora22> <5525B2AE.80301@gmail.com> <5525B62A.1050601@gmail.com> <5525D389.3010700@gmail.com> <55269FF6.4090003@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: "netdev@vger.kernel.org" , "mike@cchtml.com" , "intel-wired-lan@lists.osuosl.org" , "Ertman, David M" , "Lubetkin, YanirX" To: Alexander Duyck , Hisashi T Fujinaka Return-path: Received: from mga03.intel.com ([134.134.136.65]:2558 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753855AbbDMS0w convert rfc822-to-8bit (ORCPT ); Mon, 13 Apr 2015 14:26:52 -0400 In-Reply-To: <55269FF6.4090003@gmail.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: I checked with the HW guys, and they confirmed that a total packet size of 9022 is acceptable. The original size of 9018 was defined as: Frame size (9018) = DST (6) + SRC (6) + VLAN (4) + TYPE (2) + MTU (x) + CRC (4). If an additional 4 bytes is required, that is ok. -----Original Message----- From: Alexander Duyck [mailto:alexander.duyck@gmail.com] Sent: Thursday, April 09, 2015 18:51 To: Templeman, Chaim; Hisashi T Fujinaka Cc: netdev@vger.kernel.org; mike@cchtml.com; intel-wired-lan@lists.osuosl.org; Ertman, David M; Lubetkin, YanirX Subject: Re: [Intel-wired-lan] [PATCH] e1000e: Cleanup handling of VLAN_HLEN as a part of max frame size On 04/08/2015 11:17 PM, Templeman, Chaim wrote: > We will look into this with the HW architect and get back to you on what the HW limitations actually are on this issue. Chaim, thanks for looking into this. The key piece that would be useful to know is if the 9018 should really be 9022 if you account for both VLAN header and CRC. Based on the documentation for the Windows driver that seems to be the case as they support an MTU of 9014 excluding the 8 bytes for CRC and VLAN header. - Alex --------------------------------------------------------------------- Intel Israel (74) Limited This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.