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 9E1E9A04DD; Tue, 10 Nov 2020 16:59:39 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 84B5AF64; Tue, 10 Nov 2020 16:59:37 +0100 (CET) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 0D587DED for ; Tue, 10 Nov 2020 16:59:33 +0100 (CET) IronPort-SDR: RT7xaRsM+ltusjbhRkSbCtbAen5IzFNRp8SujKBjOXQzzfV3iJcf/2K1ItM5U8TxlTUjXEWc+o wmFWYYrwaEKw== X-IronPort-AV: E=McAfee;i="6000,8403,9801"; a="170105833" X-IronPort-AV: E=Sophos;i="5.77,466,1596524400"; d="scan'208";a="170105833" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Nov 2020 07:59:31 -0800 IronPort-SDR: Gro2ZdtaE5gN92k2ugkXmrw0rVC/kfCpvo9ygJH3fvWoCHje85JPga7s6Lzb2i5Hn3+Rw/XDj5 sCbzRE/y8b+A== X-IronPort-AV: E=Sophos;i="5.77,466,1596524400"; d="scan'208";a="541376280" Received: from fyigit-mobl1.ger.corp.intel.com (HELO [10.252.0.179]) ([10.252.0.179]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Nov 2020 07:59:30 -0800 To: Michael Pfeiffer , Keith Wiles Cc: dev@dpdk.org References: <20201109142217.115918-1-michael.pfeiffer@tu-ilmenau.de> From: Ferruh Yigit Message-ID: Date: Tue, 10 Nov 2020 15:59:29 +0000 MIME-Version: 1.0 In-Reply-To: <20201109142217.115918-1-michael.pfeiffer@tu-ilmenau.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH] net/tap: Allow all-zero checksum for UDP over IPv4 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 11/9/2020 2:22 PM, Michael Pfeiffer wrote: > Unlike TCP, UDP checksums are optional and may be zero to indicate "not > set" [RFC 768] (except for IPv6, where this prohibited [RFC 8200]). Add > this special case to the checksum offload emulation in net/tap. > > Signed-off-by: Michael Pfeiffer > --- > drivers/net/tap/rte_eth_tap.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c > index 2f8abb12c..e486b41c5 100644 > --- a/drivers/net/tap/rte_eth_tap.c > +++ b/drivers/net/tap/rte_eth_tap.c > @@ -303,6 +303,7 @@ tap_verify_csum(struct rte_mbuf *mbuf) > uint16_t cksum = 0; > void *l3_hdr; > void *l4_hdr; > + struct rte_udp_hdr *udp_hdr; > > if (l2 == RTE_PTYPE_L2_ETHER_VLAN) > l2_len += 4; > @@ -349,10 +350,18 @@ tap_verify_csum(struct rte_mbuf *mbuf) > /* Don't verify checksum for multi-segment packets. */ > if (mbuf->nb_segs > 1) > return; > - if (l3 == RTE_PTYPE_L3_IPV4) > + if (l3 == RTE_PTYPE_L3_IPV4) { > + if (l4 == RTE_PTYPE_L4_UDP) { > + udp_hdr = (struct rte_udp_hdr *)l4_hdr; > + if (udp_hdr->dgram_cksum == 0) { Overall patch looks good to me, but can you please add a comment on top of above check to describe why checksum can be zero, as done in the commit log. > + mbuf->ol_flags |= PKT_RX_L4_CKSUM_NONE; > + return; > + } > + } > cksum = ~rte_ipv4_udptcp_cksum(l3_hdr, l4_hdr); > - else if (l3 == RTE_PTYPE_L3_IPV6) > + } else if (l3 == RTE_PTYPE_L3_IPV6) { > cksum = ~rte_ipv6_udptcp_cksum(l3_hdr, l4_hdr); > + } > mbuf->ol_flags |= cksum ? > PKT_RX_L4_CKSUM_BAD : > PKT_RX_L4_CKSUM_GOOD; >