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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 591F5C433E1 for ; Thu, 13 Aug 2020 21:01:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2BF2420829 for ; Thu, 13 Aug 2020 21:01:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597352516; bh=XYjE4M7c87GPxUaODyYmsXo++g7jdEEJTfG6obbcGQM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=A6jmOMo+57LPyr0b+SDzdOmJme6ZJnllKoR/Af6zbneUznDmo54QWXchr7JnMmym5 vcX+SUlcFthV2IMMoYz97OqFDJNESei3TS29poxYaOf0kCfdz/rV+jMTVh2CPiuQhw O/o9csOjrdUCDr4/Vfuda5s1Ba6GVirQFdCEbTMc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726640AbgHMVBz (ORCPT ); Thu, 13 Aug 2020 17:01:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:35270 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726486AbgHMVBz (ORCPT ); Thu, 13 Aug 2020 17:01:55 -0400 Received: from kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com (unknown [163.114.132.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7D05720715; Thu, 13 Aug 2020 21:01:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597352514; bh=XYjE4M7c87GPxUaODyYmsXo++g7jdEEJTfG6obbcGQM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=1KC18ENBKL28GM7Ij9JNqUP1ucQbzQhDoJnXrqH13qjWZM6FiPaS3TdHl8ClfzADV 81cZQRc69nExWH4h4aHFTscM6D3u5p/2UjWN5MYceIfVlewbTIpZy+uLGpv6o1Xhgc d0riwa5/ZQyv+SPqUZBDia1Oq1vKfXeot7lUV6IU= Date: Thu, 13 Aug 2020 14:01:52 -0700 From: Jakub Kicinski To: "Jason A. Donenfeld" Cc: netdev@vger.kernel.org, Thomas Ptacek , Adhipati Blambangan , David Ahern , Toke =?UTF-8?B?SMO4aWxhbmQtSsO4cmdlbnNlbg==?= , Alexei Starovoitov Subject: Re: [PATCH net v4] net: xdp: account for layer 3 packets in generic skb handler Message-ID: <20200813140152.1aab6068@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20200813195816.67222-1-Jason@zx2c4.com> References: <20200813195816.67222-1-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 13 Aug 2020 21:58:16 +0200 Jason A. Donenfeld wrote: > - cls_bpf does not support the same feature set as XDP, and operates at > a slightly different stage in the networking stack. Please elaborate. > I had originally dropped this patch, but the issue kept coming up in > user reports, so here's a v4 of it. Testing of it is still rather slim, > but hopefully that will change in the coming days. Here an alternative patch, untested: diff --git a/net/core/dev.c b/net/core/dev.c index d3d53dc601f9..7f68831bdd4f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5434,6 +5434,11 @@ static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) struct bpf_prog *new = xdp->prog; int ret = 0; + if (!dev->hard_header_len) { + NL_SET_ERR_MSG(xdp->extack, "generic XDP not supported on L3 devices, please use cls_bpf"); + return -EINVAL; + } + if (new) { u32 i;