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 33E9BC54EBE for ; Fri, 13 Jan 2023 02:51:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229964AbjAMCvE (ORCPT ); Thu, 12 Jan 2023 21:51:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231346AbjAMCuy (ORCPT ); Thu, 12 Jan 2023 21:50:54 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BBDC45D6B9 for ; Thu, 12 Jan 2023 18:50:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673578206; 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=odERJ73Z3UfAhcbzEnILTL+WyS7927XUH/5iYtkYUew=; b=c290WSpTUlJ4nhIAORqkNQ4C/EkRTfx6KCwTcnRpihNHjezuFQNAf7BBYh8AQIl0R4Er66 SG5yHy/eTvbFRusVeFTQemfYPrH4xOJqtlSLCANdYcNMr5HN6cWGbm6wxc5mEaLT2/edgP qaui08wx1LLn+ioE1fWrgF/QuAg0hrk= Received: from mail-pg1-f197.google.com (mail-pg1-f197.google.com [209.85.215.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-50-CL4lVbhmOQqZYnpdljGpwA-1; Thu, 12 Jan 2023 21:50:05 -0500 X-MC-Unique: CL4lVbhmOQqZYnpdljGpwA-1 Received: by mail-pg1-f197.google.com with SMTP id k16-20020a635a50000000b0042986056df6so9037552pgm.2 for ; Thu, 12 Jan 2023 18:50:05 -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=odERJ73Z3UfAhcbzEnILTL+WyS7927XUH/5iYtkYUew=; b=U/R0vx1Fi5JZ+aQB5cplDrmHbK6ScL/fa3aV+Hgfxt5lMI+NZyxXZHXXHPOrRCNno0 E8RSkS68ksVfagx/Fb0DsDx/BQbebVZSbEH/kOzU6GtxIUj6s438HS4stBFpfR1sP1Xj X8lXoqE8yrQ5nsU6DE025iIZTJtzAhQvCR7Q44ZiH422VXc17RI1/1HbSLnpNF0Ngim/ 5fWZNBoVvbqViw0mwwW0SH+Q2Cv+PlXOnyTWqUb9IQwjSVwslYD6ND10y20n/pIQADKy /dyYZi0i9wNYhvbL1BLX61RS5ZS5BJtHLRvgS+gn3yFFc4UvkISxGBvnPwaf0cPW84pe 0BfA== X-Gm-Message-State: AFqh2krPtO+sa5erGjg3rTjbs0w8K9/IwQx2OKpzJAspUQ5eWf+mb5XV JkxR/6zYUpjHoW7E/WGIolBUYdp0A1DZNZw8BYZqegSjc3joXlbWag+1FZCi+2L/ko+PtAe0bcU 4ijWjLVdz7Xhq X-Received: by 2002:a17:90a:6344:b0:225:ce95:dc15 with SMTP id v4-20020a17090a634400b00225ce95dc15mr68433134pjs.29.1673578204456; Thu, 12 Jan 2023 18:50:04 -0800 (PST) X-Google-Smtp-Source: AMrXdXvjkjbMP4vKqVA3kL5O3q2YuiKZMzH0b0ScPMkUSeUY2VDrz1aY78FXrrFA3oTZm1pFUn6Fqw== X-Received: by 2002:a17:90a:6344:b0:225:ce95:dc15 with SMTP id v4-20020a17090a634400b00225ce95dc15mr68433119pjs.29.1673578204181; Thu, 12 Jan 2023 18:50:04 -0800 (PST) Received: from [10.72.12.164] ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id mn23-20020a17090b189700b00227223c58ecsm7212010pjb.42.2023.01.12.18.50.00 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 12 Jan 2023 18:50:03 -0800 (PST) Message-ID: Date: Fri, 13 Jan 2023 10:49:54 +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 v3 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: <20230103064012.108029-1-hengqi@linux.alibaba.com> <20230103064012.108029-3-hengqi@linux.alibaba.com> From: Jason Wang In-Reply-To: <20230103064012.108029-3-hengqi@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org 在 2023/1/3 14:40, 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 | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 443aa7b8f0ad..60e199811212 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -3074,7 +3074,9 @@ static int virtnet_restore_guest_offloads(struct virtnet_info *vi) > static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, > struct netlink_ext_ack *extack) > { > - unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr); > + unsigned int room = SKB_DATA_ALIGN(VIRTIO_XDP_HEADROOM + > + sizeof(struct skb_shared_info)); > + unsigned int max_sz = PAGE_SIZE - room - ETH_HLEN; > struct virtnet_info *vi = netdev_priv(dev); > struct bpf_prog *old_prog; > u16 xdp_qp = 0, curr_qp; > @@ -3095,9 +3097,9 @@ 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"); > - netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz); > + if (prog && !prog->aux->xdp_has_frags && dev->mtu > max_sz) { > + NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP without frags"); > + netdev_warn(dev, "single-buffer XDP requires MTU less than %u\n", max_sz); > return -EINVAL; > } I think we probably need to backport this to -stable. So I suggest to move/squash the check of !prog->aux->xdp_has_frags to one of the following patch. With this, Acked-by: Jason Wang Thanks >