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 1C920A0350 for ; Wed, 1 Jul 2020 15:41:03 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 5504F1C2F6; Wed, 1 Jul 2020 15:41:02 +0200 (CEST) Received: from mail-io1-f45.google.com (mail-io1-f45.google.com [209.85.166.45]) by dpdk.org (Postfix) with ESMTP id 12F381C28F for ; Wed, 1 Jul 2020 15:41:01 +0200 (CEST) Received: by mail-io1-f45.google.com with SMTP id c16so24996272ioi.9 for ; Wed, 01 Jul 2020 06:41:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=OHB6438pdCDsqlAcMncKNVnQguPpkPU9aJ8q8ML4h84=; b=DMv1hhcvZKISKH7IVsdESrQKT4wu4Q+1jpQTuVLokjBxrGnWPTzcjrQcpcJj8Y67vU Ej9izBCs/CCRURNyBB7df3iF8S/3aTqvQ8sznP43FL4uI4wjgO3hr0KiHkhGffQ3PE91 nmlNLhniTdsbaY233ek5+uBygMr9jZGNbe0ZQIFIL9lZm9dnPhMXWNUqMh8sKYiD7EJ+ 6ZK1hnUaktGM0tykjLP+DoRS2jxI29jcxWa04ouCw9LFAUYWA0Srscxn1YvqOYxJxSac zVHQo2GOp4Nlh43BVfk5l8tVYNDhLHXatQp4kIB/CExtggv9GpBBg63uhICdGPYQAlmo Gg4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=OHB6438pdCDsqlAcMncKNVnQguPpkPU9aJ8q8ML4h84=; b=cqyYvSRCPvCPmXd5/x+ttfMxnw3Z6UUI2iLVccqhd5LZB0AaRkBhaT8lvyEdx409An mYIihZl8Do2x3eG/NCobdpRHY9GW60SwDEzBrfA6aWLCi/+8H7QJiEcrUTERPIeusyv6 hbmgaLNpzQKAotM/LmNpUk93Q4optqMXs62d4vQZ9xKYQ1Z2SpGe9u+ie1ThRY04O37M QvmgO6ChwgL1YU8Uw6uyfkCwB8yCHetfqo5PjL4dbCxWDzxDWY9YNQ5BwH5Dv/uRvo3Q Mfrv1ajYKDEq6aJ1hn3rjMFgOQqGCUVTYFXgLDwRBaF6vb+x/8FUSKe5c5b9OZLKkXhm 6ogg== X-Gm-Message-State: AOAM530z/uybmLVdGJs0gnt+QrGsz3VgYC4Ca5yvPusMuw8LG0diIEi3 U+LjzpP0URXtO3L+aSj/Knxl/4ppkz/duuodrUw= X-Google-Smtp-Source: ABdhPJz5CXZkl+NC1gD11OrjQ2aX08SF8IhpiSXXUkbhW2UgY/zq6FBkua1Exfze5AwfmHBpkocfzmIpVgKMXxb3Hjs= X-Received: by 2002:a05:6638:223:: with SMTP id f3mr28777031jaq.144.1593610860273; Wed, 01 Jul 2020 06:41:00 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: David Aldrich Date: Wed, 1 Jul 2020 14:40:49 +0100 Message-ID: To: Cliff Burdick Cc: users Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: Re: [dpdk-users] Why is udp packet, sent by dpdk, received with zero'd payload? X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org Sender: "users" I think this is where my lack of understanding is my problem. Looking at the mbuf dump: dump mbuf at 0x53e4e92c0, iova=73e4e9340, buf_len=2176 pkt_len=57, ol_flags=c0000000000000, nb_segs=2, in_port=65535 segment at 0x53e4e92c0, data=0x53e4e9396, data_len=42 Dump data at [0x53e4e9396], len=42 00000000: 94 40 C9 1F C4 DB 94 40 C9 1E 13 7D 08 00 45 B8 | .@.....@...}..E. 00000010: 00 2B 00 00 00 00 40 11 F5 E8 C0 A8 01 69 C0 A8 | .+....@......i.. 00000020: 01 68 0B B9 0B B8 00 17 64 2D | | | | | | | .h......d- segment at 0x53e146e40, data=0x53e4fbbc0, data_len=15 Dump data at [0x53e4fbbc0], len=15 00000000: 48 65 6C 6C 6F 20 66 72 6F 6D 20 64 70 64 6B | | Hello from dpdk It consists of two parts (segments?), of lengths 42 and 15. This makes sense to me as I first put the payload in the mbuf (15 bytes) and then added the Ethernet and L3 headers (42 bytes) by calling rte_pktmbuf_prepend(). I guess only the first segment is getting transmitted? On Wed, Jul 1, 2020 at 1:57 PM Cliff Burdick wrote: > Are you setting data_len and packet_len in the mbuf before sending? > > > On Wed, Jul 1, 2020, 03:23 David Aldrich > wrote: > >> Hi, >> >> I have a problem transmitting udp packets with dpdk-stable-18.11.8. I have >> posted a question about it on stackoverflow: >> >> >> https://stackoverflow.com/questions/62674596/why-is-udp-packet-sent-by-dpdk-received-with-zerod-payload >> >> I would be grateful for any comments either there or in this group please. >> >> Best regards >> >> David >> >