From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [RFC net-next PATCH 2/5] mlx5: fix bug reading rss_hash_type from CQE Date: Fri, 19 May 2017 17:47:01 +0200 Message-ID: <591F1375.8020307@iogearbox.net> References: <149512205297.14733.15729847433404265933.stgit@firesoul> <149512209807.14733.12774004120782832472.stgit@firesoul> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: John Fastabend , netdev@vger.kernel.org, saeedm@mellanox.com To: Jesper Dangaard Brouer , Daniel Borkmann , Alexei Starovoitov Return-path: Received: from www62.your-server.de ([213.133.104.62]:34684 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751469AbdESPrI (ORCPT ); Fri, 19 May 2017 11:47:08 -0400 In-Reply-To: <149512209807.14733.12774004120782832472.stgit@firesoul> Sender: netdev-owner@vger.kernel.org List-ID: On 05/18/2017 05:41 PM, Jesper Dangaard Brouer wrote: > Masks for extracting part of the Completion Queue Entry (CQE) > field rss_hash_type was swapped, namely CQE_RSS_HTYPE_IP and > CQE_RSS_HTYPE_L4. > > The bug resulted in setting skb->l4_hash, even-though the > rss_hash_type indicated that hash was NOT computed over the > L4 (UDP or TCP) part of the packet. > > Added comments from the datasheet, to make it more clear what > these masks are selecting. > > Signed-off-by: Jesper Dangaard Brouer > --- Stand-alone fix for -net tree? > include/linux/mlx5/device.h | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h > index dd9a263ed368..a940ec6a046c 100644 > --- a/include/linux/mlx5/device.h > +++ b/include/linux/mlx5/device.h > @@ -787,8 +787,14 @@ enum { > }; > > enum { > - CQE_RSS_HTYPE_IP = 0x3 << 6, > - CQE_RSS_HTYPE_L4 = 0x3 << 2, > + CQE_RSS_HTYPE_IP = 0x3 << 2, > + /* cqe->rss_hash_type[3:2] - IP destination selected for hash > + * (00 = none, 01 = IPv4, 10 = IPv6, 11 = Reserved) > + */ > + CQE_RSS_HTYPE_L4 = 0x3 << 6, > + /* cqe->rss_hash_type[7:6] - L4 destination selected for hash > + * (00 = none, 01 = TCP. 10 = UDP, 11 = IPSEC.SPI > + */ > }; > > enum { >