From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C86B3C433E0 for ; Wed, 20 Jan 2021 03:04:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93F3523109 for ; Wed, 20 Jan 2021 03:04:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389466AbhATDEF (ORCPT ); Tue, 19 Jan 2021 22:04:05 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:51458 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388061AbhATDDI (ORCPT ); Tue, 19 Jan 2021 22:03:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611111702; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZodmnXn4xAMstumzC/OBLSYq3RcxDLukButfIEIAT2Y=; b=R6jhdz8kjMaMI3az+PxEM7iYoGTja6Gc8GezHQqUnv2BWWB7XIYiCZzbhBa7zReqnd0A1E 1D7NDmULhVSzD0Gxg1auFqCjEyGD89dnGP8zhf20jxUIZIsP6KJDj+18/MqMG/vetWC6Md uspBVY1y+sbuoq3oPHahEW6u2YHYY0w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-155-RfqNDkrNMjyVLRuQG31F_g-1; Tue, 19 Jan 2021 22:01:37 -0500 X-MC-Unique: RfqNDkrNMjyVLRuQG31F_g-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 105C0E743; Wed, 20 Jan 2021 03:01:35 +0000 (UTC) Received: from [10.72.13.124] (ovpn-13-124.pek2.redhat.com [10.72.13.124]) by smtp.corp.redhat.com (Postfix) with ESMTP id 02EC172171; Wed, 20 Jan 2021 03:01:25 +0000 (UTC) Subject: Re: [PATCH bpf-next v2 1/3] net: add priv_flags for allow tx skb without linear To: Xuan Zhuo , netdev@vger.kernel.org Cc: "Michael S. Tsirkin" , "David S. Miller" , Jakub Kicinski , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Magnus Karlsson , Jonathan Lemon , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , virtualization@lists.linux-foundation.org, bpf@vger.kernel.org References: <30ae1c94b5c26919bd90bb251761c526edfbaf56.1611048724.git.xuanzhuo@linux.alibaba.com> From: Jason Wang Message-ID: <13d2ceda-16d1-488c-d131-55cca813b224@redhat.com> Date: Wed, 20 Jan 2021 11:01:24 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <30ae1c94b5c26919bd90bb251761c526edfbaf56.1611048724.git.xuanzhuo@linux.alibaba.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2021/1/19 下午5:45, Xuan Zhuo wrote: > In some cases, we hope to construct skb directly based on the existing > memory without copying data. In this case, the page will be placed > directly in the skb, and the linear space of skb is empty. But > unfortunately, many the network card does not support this operation. > For example Mellanox Technologies MT27710 Family [ConnectX-4 Lx] will > get the following error message: > > mlx5_core 0000:3b:00.1 eth1: Error cqe on cqn 0x817, ci 0x8, qn 0x1dbb, opcode 0xd, syndrome 0x1, vendor syndrome 0x68 > 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > 00000030: 00 00 00 00 60 10 68 01 0a 00 1d bb 00 0f 9f d2 > WQE DUMP: WQ size 1024 WQ cur size 0, WQE index 0xf, len: 64 > 00000000: 00 00 0f 0a 00 1d bb 03 00 00 00 08 00 00 00 00 > 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > 00000020: 00 00 00 2b 00 08 00 00 00 00 00 05 9e e3 08 00 > 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > mlx5_core 0000:3b:00.1 eth1: ERR CQE on SQ: 0x1dbb > > So a priv_flag is added here to indicate whether the network card > supports this feature. I don't see Mellanox engineers are copied. I wonder if we need their confirmation on whether it's a bug or hardware limitation. Thanks