From patchwork Thu Aug 26 23:26:58 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Christoph Lameter (Ampere)" X-Patchwork-Id: 62812 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 8CD84B70DD for ; Fri, 27 Aug 2010 09:27:09 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753843Ab0HZX1F (ORCPT ); Thu, 26 Aug 2010 19:27:05 -0400 Received: from smtp104.prem.mail.ac4.yahoo.com ([76.13.13.43]:31422 "HELO smtp104.prem.mail.ac4.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752217Ab0HZX1D (ORCPT ); Thu, 26 Aug 2010 19:27:03 -0400 Received: (qmail 13254 invoked from network); 26 Aug 2010 23:27:00 -0000 Received: from router.home (cl@99.30.10.212 with plain) by smtp104.prem.mail.ac4.yahoo.com with SMTP; 26 Aug 2010 16:27:00 -0700 PDT X-Yahoo-SMTP: _Dag8S.swBC1p4FJKLCXbs8NQzyse1SYSgnAbY0- X-YMail-OSG: kPsSSwoVM1kAF8fs3IvZIsSkRtvyCtM7pGmz0GXm0v03bZm yEkNza4YZXtPltdVgU365wSFw66eVy4Ar63o1syJrSLFO6oo5UJQm_82mCJG IDk5y7psFE.1zatO9o_gWI72EgfBdozqolQ2gLRueACVQJyq2Rtoqxopz9ui OecjxLHyEngiUUNUXIo4rjM_apdoW1mhwJcSa_M7wdCvZqFLEqnV9i5o8GZJ 8J9.FevNW6cuSken_2Vme3C0a_PJ6p6_TiQ-- X-Yahoo-Newman-Property: ymail-3 Received: from cl (helo=localhost) by router.home with local-esmtp (Exim 4.71) (envelope-from ) id 1OolqW-0007Zq-0a; Thu, 26 Aug 2010 18:27:00 -0500 Date: Thu, 26 Aug 2010 18:26:58 -0500 (CDT) From: Christoph Lameter X-X-Sender: cl@router.home To: Jason Gunthorpe cc: David Miller , rdreier@cisco.com, linux-rdma@vger.kernel.org, ogerlitz@voltaire.com, yosefe@voltaire.com, netdev@vger.kernel.org Subject: Re: [IPoIB] Identify multicast packets and fix IGMP breakage V3 In-Reply-To: <20100826222146.GA23025@obsidianresearch.com> Message-ID: References: <20100826.151553.242147157.davem@davemloft.net> <20100826222146.GA23025@obsidianresearch.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 26 Aug 2010, Jason Gunthorpe wrote: > The 40 bytes at this location are defined by the HW specification to > be an IB GRH which has an identical layout to an IPv6 header. Roland > is right, it would be clearer to use ib_grh ->dgid Ok but then we have no nice function that checks for multicast anymore. Subject: [IPoIB] Identify multicast packets and fix IGMP breakage V3 IGMP processing is broken because the IPOIB does not set the skb->pkt_type the right way for Multicast traffic. All incoming packets are set to PACKET_HOST which means that the igmp_recv() function will ignore the IGMP broadcasts/multicasts. This in turn means that the IGMP timers are firing and are sending information about multicast subscriptions unnecessarily. In a large private network this can cause traffic spikes. Signed-off-by: Christoph Lameter --- -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-2.6/drivers/infiniband/ulp/ipoib/ipoib_ib.c =================================================================== --- linux-2.6.orig/drivers/infiniband/ulp/ipoib/ipoib_ib.c 2010-08-26 18:24:07.842079559 -0500 +++ linux-2.6/drivers/infiniband/ulp/ipoib/ipoib_ib.c 2010-08-26 18:25:33.859815544 -0500 @@ -271,6 +271,14 @@ ipoib_ud_dma_unmap_rx(priv, mapping); ipoib_ud_skb_put_frags(priv, skb, wc->byte_len); + /* First byte of dgid signals multicast when 0xff */ + if ((wc->wc_flags & IB_WC_GRH) && + ((struct ib_grh *)skb->data)->dgid.raw[0] == 0xff) + + skb->pkt_type = PACKET_MULTICAST; + else + skb->pkt_type = PACKET_HOST; + skb_pull(skb, IB_GRH_BYTES); skb->protocol = ((struct ipoib_header *) skb->data)->proto; @@ -281,9 +289,6 @@ dev->stats.rx_bytes += skb->len; skb->dev = dev; - /* XXX get correct PACKET_ type here */ - skb->pkt_type = PACKET_HOST; - if (test_bit(IPOIB_FLAG_CSUM, &priv->flags) && likely(wc->csum_ok)) skb->ip_summed = CHECKSUM_UNNECESSARY;