From patchwork Wed Mar 13 18:46:45 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Gallatin X-Patchwork-Id: 227320 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 0D02F2C009C for ; Thu, 14 Mar 2013 05:47:07 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933024Ab3CMSrD (ORCPT ); Wed, 13 Mar 2013 14:47:03 -0400 Received: from mail-gh0-f179.google.com ([209.85.160.179]:42601 "EHLO mail-gh0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756375Ab3CMSrB (ORCPT ); Wed, 13 Mar 2013 14:47:01 -0400 Received: by mail-gh0-f179.google.com with SMTP id r14so234898ghr.10 for ; Wed, 13 Mar 2013 11:47:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer :x-gm-message-state; bh=6PGvyLmEE56DbD8PWpWL8FAocYdBf0E5pIiA97Bv4Ts=; b=dXWlMUQ106UrPX+jDQyeyEq9SoXSUjq9faXdt5XGgu1+RDvtmWnNZ/Ja6H4yFcK53z GfxHfyodvcR/PHgbG5Nnqty1ref6xcf26T6mliM6GuDbivgOdDV8WOEuzWjw2rOPnHMT ET/2SJ7LNZIqmj9oASEZLNiT3S3icVmciv/A3M25YeCbf1RcrzWKb3ri+Jkds97exezR ZeIluMEXoN9wNMux9D7DqUvHzW3ibWahngAgrGaFu96brek0JK/9tKFujmOkiWbAbEWg /WybWYV0n04nyYlyY1BRgY9TTheprzNGWWhdE9RAn0D1kKsgWDZsk7asVIXpq6lkpLHg /NJg== X-Received: by 10.236.175.67 with SMTP id y43mr16890501yhl.162.1363200420307; Wed, 13 Mar 2013 11:47:00 -0700 (PDT) Received: from drogon.sw.myri.com (c-24-127-11-217.hsd1.va.comcast.net. [24.127.11.217]) by mx.google.com with ESMTPS id u3sm36959813yhd.14.2013.03.13.11.46.57 (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 13 Mar 2013 11:46:58 -0700 (PDT) From: Andrew Gallatin To: davem@davemloft.net, gregkh@linuxfoundation.org Cc: stable@vger.kernel.org, netdev@vger.kernel.org, Andrew Gallatin Subject: [PATCH v3.4-stable] myri10ge: Restrict LRO max_aggr based on MTU Date: Wed, 13 Mar 2013 14:46:45 -0400 Message-Id: <1363200405-17839-1-git-send-email-gallatin@myri.com> X-Mailer: git-send-email 1.7.9.5 X-Gm-Message-State: ALoCoQmSA9ANOfSsK3bJ1/kX4Ys08KZ1ca/rM7YzKLtxd1A+zcHgLg3KrGPBNBV1fQC1oeECHJHO Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Fix a longstanding panic when myri10ge would configure lro_mgr->max_aggr wrong, so that lro could aggregate more than MAX_SKB_FRAGS frags when jumbo frames (which consume multiple frags) are used. To fix this, we determine the frags per packet in excess of MAX_SKB_FRAGS for the current MTU, and subtract those extra frags from MAX_SKB_FRAGS when configuring lro_mgr->max_aggr to ensure that MAX_SKB_FRAGS will not be exceeded. This does not apply to the mainline, because LRO was removed from myri10ge when it was converted to use GRO in 4ca3221 (appeared in 3.8). It should probably be merged to all active stable kernels prior to 3.8, since it fixes a panic. Signed-off-by: Andrew Gallatin --- drivers/net/ethernet/myricom/myri10ge/myri10ge.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c index 27273ae..99fa774 100644 --- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c +++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c @@ -2406,7 +2406,7 @@ static int myri10ge_open(struct net_device *dev) struct myri10ge_slice_state *ss; struct myri10ge_priv *mgp = netdev_priv(dev); struct myri10ge_cmd cmd; - int i, status, big_pow2, slice; + int i, status, big_pow2, slice, extra_frags; u8 *itable; struct net_lro_mgr *lro_mgr; @@ -2529,8 +2529,10 @@ static int myri10ge_open(struct net_device *dev) lro_mgr->get_frag_header = myri10ge_get_frag_header; lro_mgr->max_aggr = myri10ge_lro_max_pkts; lro_mgr->frag_align_pad = 2; - if (lro_mgr->max_aggr > MAX_SKB_FRAGS) - lro_mgr->max_aggr = MAX_SKB_FRAGS; + extra_frags = (dev->mtu + ETH_HLEN + VLAN_HLEN + MXGEFW_PAD) / + MYRI10GE_ALLOC_SIZE; + if (lro_mgr->max_aggr > MAX_SKB_FRAGS - extra_frags) + lro_mgr->max_aggr = MAX_SKB_FRAGS - extra_frags; /* must happen prior to any irq */ napi_enable(&(ss)->napi);