From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 32BD0A04B1; Wed, 4 Nov 2020 18:08:10 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 519372BFE; Wed, 4 Nov 2020 18:08:08 +0100 (CET) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by dpdk.org (Postfix) with ESMTP id A79222BD3 for ; Wed, 4 Nov 2020 18:08:06 +0100 (CET) IronPort-SDR: efaDjowftGB2Xo63VfXa00ojKpj6kQ1wAkH5Nw2rOjQLdZNc2s9nqzpX7BzcOjIVaNqktK/nGn /FD3BYwwyFPg== X-IronPort-AV: E=McAfee;i="6000,8403,9795"; a="148532043" X-IronPort-AV: E=Sophos;i="5.77,451,1596524400"; d="scan'208";a="148532043" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Nov 2020 09:07:49 -0800 IronPort-SDR: oLZSt50d2pJyXcq+unKinir5S8LazPjrEAFTAdD3e3055fbvcINg7Ba9UBIOIrHw3y9TvcTZIQ 8esLcgeI1DLw== X-IronPort-AV: E=Sophos;i="5.77,451,1596524400"; d="scan'208";a="353903809" Received: from fyigit-mobl1.ger.corp.intel.com (HELO [10.213.228.199]) ([10.213.228.199]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Nov 2020 09:07:46 -0800 To: Thomas Monjalon , SteveX Yang Cc: dev@dpdk.org, konstantin.ananyev@intel.com, beilei.xing@intel.com, wenzhuo.lu@intel.com, bernard.iremonger@intel.com, qiming.yang@intel.com, mdr@ashroe.eu, nhorman@tuxdriver.com, david.marchand@redhat.com, andrew.rybchenko@oktetlabs.ru References: <20201028030334.30300-1-stevex.yang@intel.com> <13f49ee0-8cee-5f1b-e3bb-0d3a54e9e189@intel.com> <5676659a-980c-7f13-caa9-d83a5f89c700@intel.com> <2392354.O08QGPWUWg@thomas> From: Ferruh Yigit Message-ID: <13d2c6ad-c14b-b471-5920-ec3c552b7a61@intel.com> Date: Wed, 4 Nov 2020 17:07:42 +0000 MIME-Version: 1.0 In-Reply-To: <2392354.O08QGPWUWg@thomas> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH v8 1/2] app/testpmd: fix max rx packet length for VLAN packets X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 11/4/2020 4:51 PM, Thomas Monjalon wrote: > 03/11/2020 14:29, Ferruh Yigit: >> On 11/2/2020 11:48 AM, Ferruh Yigit wrote: >>> On 11/2/2020 8:52 AM, SteveX Yang wrote: >>>> When the max rx packet length is smaller than the sum of mtu size and >>>> ether overhead size, it should be enlarged, otherwise the VLAN packets >>>> will be dropped. >>>> >>>> Fixes: 35b2d13fd6fd ("net: add rte prefix to ether defines") >>>> >>>> Signed-off-by: SteveX Yang >>> >>> Reviewed-by: Ferruh Yigit >> >> Applied to dpdk-next-net/main, thanks. >> >> only 1/2 applied since discussion is going on for 2/2. > > I'm not sure this testpmd change is good. > > Reminder: testpmd is for testing the PMDs. > Don't we want to see VLAN packets dropped in the case described above? > The patch set 'max_rx_pkt_len' in a way to make MTU 1500 for all PMDs, otherwise testpmd set hard-coded 'RTE_ETHER_MAX_LEN' value, which makes MTU between 1492-1500 depending on PMD. It is application responsibility to provide correct 'max_rx_pkt_len'. I guess the original intention was to set MTU as 1500 but was not correct for all PMDs and this patch is fixing it. The same problem in the ethdev, (assuming 'RTE_ETHER_MAX_LEN' will give MTU 1500), the other patch in the set is to fix it later.