From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: Regarding offloading IPv6 addrconf and ndisc Date: Tue, 1 Aug 2006 02:31:58 +0200 Message-ID: <200608010231.58339.ak@suse.de> References: <44C8B0B8.2010408@miyazawa.org> <20060727.183415.104032934.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: herbert@gondor.apana.org.au, kazunori@miyazawa.org, yoshfuji@linux-ipv6.org, netdev@vger.kernel.org, usagi-core@linux-ipv6.org Return-path: Received: from mx2.suse.de ([195.135.220.15]:7352 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1030357AbWHAAcV (ORCPT ); Mon, 31 Jul 2006 20:32:21 -0400 To: David Miller In-Reply-To: <20060727.183415.104032934.davem@davemloft.net> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org > If we process these in sequence in software interrupt, everything > is fine. Processing of "A" will add the address, and the test > ping packet "B" will respond properly. > > If you defer "A", everything breaks and the test packet "B" will > get processed first and not work. Playing devil's advocate here: if the packets are processed on two different CPUs then this could also happen and break the test case. So the test is probably a bit fragile. Currently it is unlikely to happen because of interrupt affinity for a single device, but in future with MSI-X support it might not. I generally agree it's better to keep this in kernel though. -Andi