Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757497AbZKROiE (ORCPT ); Wed, 18 Nov 2009 09:38:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757407AbZKROiC (ORCPT ); Wed, 18 Nov 2009 09:38:02 -0500 Received: from out02.mta.xmission.com ([166.70.13.232]:49405 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757216AbZKROh6 (ORCPT ); Wed, 18 Nov 2009 09:37:58 -0500 To: Arnd Bergmann Cc: Eric Dumazet , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, David Miller , Stephen Hemminger , Herbert Xu , Patrick McHardy , Patrick Mullaney , Edge Virtual Bridging , Anna Fischer , bridge@lists.linux-foundation.org, virtualization@linux-foundation.com, Jens Osterkamp , Gerhard Stenzel Subject: Re: [PATCH 1/3] macvlan: Reflect macvlan packets meant for other macvlan devices References: <1258497551-25959-1-git-send-email-arnd@arndb.de> <1258497551-25959-2-git-send-email-arnd@arndb.de> <4B03949D.4000908@gmail.com> <200911181047.07974.arnd@arndb.de> From: ebiederm@xmission.com (Eric W. Biederman) Date: Wed, 18 Nov 2009 06:37:50 -0800 In-Reply-To: <200911181047.07974.arnd@arndb.de> (Arnd Bergmann's message of "Wed\, 18 Nov 2009 10\:47\:07 +0100") Message-ID: User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-XM-SPF: eid=;;;mid=;;;hst=in02.mta.xmission.com;;;ip=76.21.114.89;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 76.21.114.89 X-SA-Exim-Mail-From: ebiederm@xmission.com X-SA-Exim-Version: 4.2.1 (built Thu, 25 Oct 2007 00:26:12 +0000) X-SA-Exim-Scanned: No (on in02.mta.xmission.com); Unknown failure Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1541 Lines: 45 Arnd Bergmann writes: > On Wednesday 18 November 2009, Eric Dumazet wrote: >> > - skb->dev = dev; >> > - skb->pkt_type = PACKET_HOST; >> > + skb->protocol = eth_type_trans(skb, dev); >> > + eth = eth_hdr(skb); >> > >> > - netif_rx(skb); >> > - return NULL; >> > + skb_dst_drop(skb); >> >> Why do you drop dst here ? >> >> It seems strange, since this driver specifically masks out IFF_XMIT_DST_RELEASE >> in its macvlan_setup() : >> >> dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; >> >> If we really want to drop dst, it could be done by caller, if IFF_XMIT_DST_RELEASE >> was not masked in macvlan_setup(). >> > > That must be my fault, it is the only change I did to Eric B's patch when > forward-porting to 2.6.32. The original patch did > > skb->protocol = eth_type_trans(skb, dev); > eth = eth_hdr(skb); > dst_release(skb->dst); > skb->dst = NULL; > skb->mark = 0; > > and I tried to convert that in the same way that other drivers did, but I > have to admit that I did not understand the mechanics of IFF_XMIT_DST_RELEASE. Please copy and ideally share code with the veth driver for recycling a skb. There are bunch of little things you have to do to get it right. As I recally I was missing a few details in my original patch. Eric -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/