From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [patch net-next v2] ipv6: log autoconfiguration failures Date: Thu, 12 Dec 2013 12:58:18 -0500 Message-ID: <52A9F93A.5040104@gmail.com> References: <1386762314-5149-1-git-send-email-dvlasenk@redhat.com> <20131211192138.GB4675@order.stressinduktion.org> <52A99B56.1070503@redhat.com> <20131212.122241.2022824170198915190.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kuznet@ms2.inr.ac.ru, jmorris@namei.org, yoshfuji@linux-ipv6.org, kaber@trash.net, jpirko@redhat.com To: David Miller , dvlasenk@redhat.com Return-path: In-Reply-To: <20131212.122241.2022824170198915190.davem@davemloft.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 12/12/2013 12:22 PM, David Miller wrote: > From: Denys Vlasenko > Date: Thu, 12 Dec 2013 12:17:42 +0100 > >> I can easily imagine their frustration. Kernel _knows_ why >> it didn't work, and it's not expected to normally pappen, >> why didn't it tell anything about it? > > Packets are dropped silently, ARP fails and entries go stale silently, > none of this is logged with kernel messages, why is ipv6 autoconf so > unique and important to justify different behavior? But most of the changes from V2 report an actual error condition in the kernel: addr_len is not set correctly for the device type. These changes are worth keeping and not just as pr_debug. Having a counter of these failures will not provide much useful data if you happen to have multiple such device and where one happens to work and the other doesn't (very unlikely, I know). > > Give it statistics just like we have for every other kind of similar > event. The fact that link-local address could not be generated for a specific device type does not lend itself well to counting. There is no way from to tell from the counter which device does not support IPv6 autoconfig. -vlad