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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 CF618C48BE0 for ; Fri, 11 Jun 2021 15:25:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADD82613DE for ; Fri, 11 Jun 2021 15:25:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231698AbhFKP1b (ORCPT ); Fri, 11 Jun 2021 11:27:31 -0400 Received: from mga06.intel.com ([134.134.136.31]:48614 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231679AbhFKP1b (ORCPT ); Fri, 11 Jun 2021 11:27:31 -0400 IronPort-SDR: sWDJ07TzeUUCoa5rohlIjbOrclK6hObyjWKxfIE4kRRC0epM1JG2s/PcG2tilwjyoIpeqalLhv hbTw9XeLJSXQ== X-IronPort-AV: E=McAfee;i="6200,9189,10012"; a="266695236" X-IronPort-AV: E=Sophos;i="5.83,265,1616482800"; d="scan'208";a="266695236" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jun 2021 08:25:32 -0700 IronPort-SDR: ZqiQIQQUh0QmOX+Mf8/WNsTGQMXPGbeew8tTM/Y4GTULg5Q7y0eJUahjzJ+U3+MeiEINwhbV92 YKcgMROJS5zw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,265,1616482800"; d="scan'208";a="553436010" Received: from ranger.igk.intel.com ([10.102.21.164]) by fmsmga001.fm.intel.com with ESMTP; 11 Jun 2021 08:25:29 -0700 Date: Fri, 11 Jun 2021 17:12:45 +0200 From: Maciej Fijalkowski To: Xuan Zhuo Cc: netdev@vger.kernel.org, Jesse Brandeburg , Tony Nguyen , "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Jeff Kirsher , =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , intel-wired-lan@lists.osuosl.org, bpf@vger.kernel.org Subject: Re: [PATCH net] ixgbe: xsk: fix for metasize when construct skb by xdp_buff Message-ID: <20210611151245.GA31289@ranger.igk.intel.com> References: <20210609122244.52647-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210609122244.52647-1-xuanzhuo@linux.alibaba.com> User-Agent: Mutt/1.12.1 (2019-06-15) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Wed, Jun 09, 2021 at 08:22:44PM +0800, Xuan Zhuo wrote: > We should copy data_meta to the skb space. Then use __skb_pull to > correct skb->data This looks like a bug that has been sitting over here for sometime. Have you encountered this during your virtio-net's AF_XDP ZC work? I'm all ears how you spotted this. Anyway, other drivers needs such fixing too. Are you willing to do that or should we take it on our side? Magnus is OOO today, I'd like to get his final ack on that. >From me: Reviewed-by: Maciej Fijalkowski Thanks! > > Fixes: d0bcacd0a1309 ("ixgbe: add AF_XDP zero-copy Rx support") > Signed-off-by: Xuan Zhuo > --- > drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c > index f72d2978263b..ee88107fa57a 100644 > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c > @@ -204,7 +204,7 @@ static struct sk_buff *ixgbe_construct_skb_zc(struct ixgbe_ring *rx_ring, > struct ixgbe_rx_buffer *bi) > { > unsigned int metasize = bi->xdp->data - bi->xdp->data_meta; > - unsigned int datasize = bi->xdp->data_end - bi->xdp->data; > + unsigned int datasize = bi->xdp->data_end - bi->xdp->data_meta; > struct sk_buff *skb; > > /* allocate a skb to store the frags */ > @@ -214,10 +214,12 @@ static struct sk_buff *ixgbe_construct_skb_zc(struct ixgbe_ring *rx_ring, > if (unlikely(!skb)) > return NULL; > > - skb_reserve(skb, bi->xdp->data - bi->xdp->data_hard_start); > - memcpy(__skb_put(skb, datasize), bi->xdp->data, datasize); > - if (metasize) > + skb_reserve(skb, bi->xdp->data_meta - bi->xdp->data_hard_start); > + memcpy(__skb_put(skb, datasize), bi->xdp->data_meta, datasize); > + if (metasize) { > + __skb_pull(skb, metasize); > skb_metadata_set(skb, metasize); > + } > > xsk_buff_free(bi->xdp); > bi->xdp = NULL; > -- > 2.31.0 >