Delivered-To: avagin@gmail.com Received: by 10.229.236.21 with SMTP id ki21cs133042qcb; Mon, 11 Oct 2010 08:24:03 -0700 (PDT) Received: by 10.224.96.200 with SMTP id i8mr4527147qan.152.1286810642441; Mon, 11 Oct 2010 08:24:02 -0700 (PDT) Return-Path: Received: from vzorg.swsoft.net (openvz.org [64.131.90.7]) by mx.google.com with ESMTP id u28si10063991qco.162.2010.10.11.08.24.01; Mon, 11 Oct 2010 08:24:02 -0700 (PDT) Received-SPF: pass (google.com: domain of avagin@openvz.org designates 64.131.90.7 as permitted sender) client-ip=64.131.90.7; Authentication-Results: mx.google.com; spf=pass (google.com: domain of avagin@openvz.org designates 64.131.90.7 as permitted sender) smtp.mail=avagin@openvz.org Received: from mx1.parallels.com (mx1.parallels.com [64.131.89.18]) by vzorg.swsoft.net (8.13.1/8.13.1) with ESMTP id o9BFO1Jx029765 for ; Mon, 11 Oct 2010 11:24:01 -0400 Received: from mailhub.sw.ru ([195.214.232.25] helo=relay.sw.ru) by mx1.parallels.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.71) (envelope-from ) id 1P5KEL-0006pD-1V for avagin@openvz.org; Mon, 11 Oct 2010 11:24:01 -0400 Received: from dhcp-10-30-18-117.sw.ru ([10.30.21.236]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id o9BFKqSY004037; Mon, 11 Oct 2010 19:20:53 +0400 (MSD) From: Andrey Vagin To: stable@kernel.org Cc: netdev@vger.kernel.org, Krishna Kumar , "David S. Miller" , Andrey Vagin Subject: [STABLE 2.6.32 PATCH] net: release dst entry while cache-hot for GSO case too Date: Mon, 11 Oct 2010 19:20:13 +0400 Message-Id: <1286810413-30238-1-git-send-email-avagin@openvz.org> X-Mailer: git-send-email 1.7.2.1 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.0.2 (vzorg.swsoft.net [64.131.90.7]); Mon, 11 Oct 2010 11:24:01 -0400 (EDT) From: Krishna Kumar commit 068a2de57ddf4f472e32e7af868613c574ad1d88 upstream. Non-GSO code drops dst entry for performance reasons, but the same is missing for GSO code. Drop dst while cache-hot for GSO case too. Note: Without this patch the kernel may oops if used bridged veth devices. A bridge set skb->dst = fake_dst_ops, veth transfers this skb to netif_receive_skb...ip_rcv_finish and it calls dst_input(skb), but fake_dst_ops->input = NULL -> Oops Signed-off-by: Krishna Kumar Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Andrey Vagin --- net/core/dev.c | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 915d0ae..c325ab6 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1747,6 +1747,14 @@ gso: skb->next = nskb->next; nskb->next = NULL; + + /* + * If device doesnt need nskb->dst, release it right now while + * its hot in this cpu cache + */ + if (dev->priv_flags & IFF_XMIT_DST_RELEASE) + skb_dst_drop(nskb); + rc = ops->ndo_start_xmit(nskb, dev); if (unlikely(rc != NETDEV_TX_OK)) { nskb->next = skb->next; -- 1.7.2.1