From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Dichtel Subject: Re: [PATCH net] net: Clear local_df only if crossing namespace. Date: Wed, 12 Feb 2014 10:32:49 +0100 Message-ID: <52FB3FC1.8080603@6wind.com> References: <1391811158-11433-1-git-send-email-pshelar@nicira.com> <20140207222840.GD16198@order.stressinduktion.org> <20140208005843.GE16198@order.stressinduktion.org> <20140211021150.GB11150@order.stressinduktion.org> Reply-To: nicolas.dichtel@6wind.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE To: Pravin Shelar , David Miller , netdev , "Templin, Fred L" , Steffen Klassert Return-path: Received: from mail-ee0-f51.google.com ([74.125.83.51]:44388 "EHLO mail-ee0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752020AbaBLJcw (ORCPT ); Wed, 12 Feb 2014 04:32:52 -0500 Received: by mail-ee0-f51.google.com with SMTP id b57so4206232eek.10 for ; Wed, 12 Feb 2014 01:32:51 -0800 (PST) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: Le 12/02/2014 05:26, Pravin Shelar a =E9crit : > On Mon, Feb 10, 2014 at 6:11 PM, Hannes Frederic Sowa > wrote: >> On Mon, Feb 10, 2014 at 01:00:14PM -0800, Pravin Shelar wrote: >>> On Fri, Feb 7, 2014 at 4:58 PM, Hannes Frederic Sowa >>> wrote: >>>> May I know because of wich vport, vxlan or gre, you did this chang= e? >>>> >>> It affects both gre and vxlan. >> >> Ok, thanks. >> >>>> I am feeling a bit uncomfortable handling remote and local packets= that >>>> differently on lower tunnel output (local_df is mostly set on loca= lly >>>> originating packets). >>> >>> For ip traffic it make sense to turn on local_df only for local >>> traffic, since for remote case we can send icmp (frag-needed) back = to >>> source. No such thing exist for OVS tunnels. ICMP packet are not >>> returned to source for the tunnels. That is why to be on safe side, >>> local_df is turned on for tunnels in OVS. >> >> I have a proposal: >> >> I don't like it that much because of the many arguments. But I curre= ntly >> don't see another easy solution. Maybe we should make bool xnet an e= num and >> test with bitops? >> >> I left the clearing of local_df in skb_scrub_packet as we need it fo= r the >> dev_forward_skb case and it should be done that in any case. >> >> This diff is slightly compile tested. ;) >> >> I can test and make proper submit if you agree. >> >> What do you think? >> > > I am not sure why the caller can not just set skb->local_df before > calling iptunnel_xmit() rather than passing extra arg to this > function? > There are not that many caller of this function. The benefit is that it ensures that future callers will think about thi= s point ;-) Steffen is reworking vti code and will use skb_scrub_packet(), I CC'ed = him in case he has some comment about this change. Regards, Nicolas