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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1BAEC10F1B for ; Tue, 27 Dec 2022 06:33:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229936AbiL0GdV (ORCPT ); Tue, 27 Dec 2022 01:33:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229961AbiL0GdL (ORCPT ); Tue, 27 Dec 2022 01:33:11 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFFFA3BE for ; Mon, 26 Dec 2022 22:32:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1672122751; 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=aPmuqzn4nncHHPF0mSfrt/O6uFSxH0gzkjB0fGhp5og=; b=H2uDYm+A5C10JzdelrravglRV3i2o4TIfmYm/Sp7XhNJx1Y0Y3kM4za7mE5P7RHkB42GLQ 36txHiCeCDYOrRzEZhMsZPpdYbtG6HrFPCykIUBm1R+yZHZ3bQIeGSYLB8Sk/N/NUoEs5E SB3byo9UwdYwOMEzR/tQ72Rmx0UmqXw= Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-163-SpDzo_LYOcOYkFGBuHVNpQ-1; Tue, 27 Dec 2022 01:32:28 -0500 X-MC-Unique: SpDzo_LYOcOYkFGBuHVNpQ-1 Received: by mail-pf1-f197.google.com with SMTP id k127-20020a628485000000b0058029fb70a3so6558303pfd.19 for ; Mon, 26 Dec 2022 22:32:28 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=aPmuqzn4nncHHPF0mSfrt/O6uFSxH0gzkjB0fGhp5og=; b=RhCbcG5wMD9lOFJozVcn0yIClDB/JoWX5qGwuieKiE0DnrQMk0qNFYU67uq1Onv9eg 7S0V9SXb4mblcIRWyAd+VcGvsryXiZXn7sb1HEHYQuHMwkjoK3lywsJI2r5AwAfKO6jh um5XKGMBa/96MorHzNgk4AH5dCZ06yBTUBcbrjkmM8nUcjUAjqBTEdzQbZfMBEKq6/yr +XADT9bo3ugoTA+m72bc3tnyTvd87V1fd9q4yDpZte1HZSoo0aKPIDPB9hpHpUsQdQlo KMZcMNHyHRWdPlEkOxILyxy6yoVUiyukidtsT16444uTJ1cSx+5tXaklAx/BKRsb3jQj UCXw== X-Gm-Message-State: AFqh2kp1vC4yqdAQSlBFYZDSSKQkGTki+Be93cC2d6vHJPG0YlvUCLsX 1WEcFOZ1g7A6lr1qeJ1+nBw7y2Lo2MnQPiLlXcxN79fE9kMM0v1kmf6bYyVyHKemlJU1nAs88CH xEi2CWm74J3mlvUF/ X-Received: by 2002:a17:902:6b4c:b0:18f:9cfb:42aa with SMTP id g12-20020a1709026b4c00b0018f9cfb42aamr22045680plt.10.1672122747706; Mon, 26 Dec 2022 22:32:27 -0800 (PST) X-Google-Smtp-Source: AMrXdXsrAnVNmNt22zl34xlV/FnvjFVshRXkKyTIIxTV5+bWVoE6t8kn2NguNc4g3QX4X8EQwBapUA== X-Received: by 2002:a17:902:6b4c:b0:18f:9cfb:42aa with SMTP id g12-20020a1709026b4c00b0018f9cfb42aamr22045664plt.10.1672122747491; Mon, 26 Dec 2022 22:32:27 -0800 (PST) Received: from [10.72.13.143] ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id x2-20020a170902ec8200b0017f72a430adsm8245068plg.71.2022.12.26.22.32.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 26 Dec 2022 22:32:27 -0800 (PST) Message-ID: <82eb2ffc-ce97-0c76-f7bc-8a163968cde7@redhat.com> Date: Tue, 27 Dec 2022 14:32:22 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.6.1 Subject: Re: [PATCH v2 2/9] virtio_net: set up xdp for multi buffer packets Content-Language: en-US To: Heng Qi , netdev@vger.kernel.org, bpf@vger.kernel.org Cc: "Michael S . Tsirkin" , Paolo Abeni , Jakub Kicinski , John Fastabend , "David S . Miller" , Daniel Borkmann , Alexei Starovoitov , Eric Dumazet , Xuan Zhuo References: <20221220141449.115918-1-hengqi@linux.alibaba.com> <20221220141449.115918-3-hengqi@linux.alibaba.com> From: Jason Wang In-Reply-To: <20221220141449.115918-3-hengqi@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 在 2022/12/20 22:14, Heng Qi 写道: > When the xdp program sets xdp.frags, which means it can process > multi-buffer packets over larger MTU, so we continue to support xdp. > But for single-buffer xdp, we should keep checking for MTU. > > Signed-off-by: Heng Qi > Reviewed-by: Xuan Zhuo > --- > drivers/net/virtio_net.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 443aa7b8f0ad..c5c4e9db4ed3 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -3095,8 +3095,8 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, > return -EINVAL; > } > > - if (dev->mtu > max_sz) { > - NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP"); > + if (prog && !prog->aux->xdp_has_frags && dev->mtu > max_sz) { Not related to this patch, but I see:         unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr); Which is suspicious, do we need to count reserved headroom/tailroom as well? Thanks > + NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP without frags"); > netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz); > return -EINVAL; > }