From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: regression when connecting to ipv6 localhost Date: Tue, 16 Oct 2012 18:43:07 +0200 Message-ID: <1350405787.3954.1229.camel@edumazet-glaptop> References: <1350242941.21172.17023.camel@edumazet-glaptop> <1350244485.21172.17077.camel@edumazet-glaptop> <1350246314.21172.17139.camel@edumazet-glaptop> <1350246414.21172.17144.camel@edumazet-glaptop> <1350246481.21172.17147.camel@edumazet-glaptop> <1350248858.21172.17197.camel@edumazet-glaptop> <1350250542.21172.17229.camel@edumazet-glaptop> <1350252091.21172.17257.camel@edumazet-glaptop> <1350279753.21172.17290.camel@edumazet-glaptop> <1350285275.22442.17.camel@joe-AO722> <1350286790.21172.17414.camel@edumazet-glaptop> <1350300302.22442.25.camel@joe-AO722> <1350304308.3954.66.camel@edumazet-glaptop> <1350307293.3954.119.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Jan Hinnerk Stosch Return-path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:33627 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755016Ab2JPQnM (ORCPT ); Tue, 16 Oct 2012 12:43:12 -0400 Received: by mail-bk0-f46.google.com with SMTP id jk13so3128338bkc.19 for ; Tue, 16 Oct 2012 09:43:11 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2012-10-16 at 18:07 +0200, Jan Hinnerk Stosch wrote: > 2012/10/15 Jan Hinnerk Stosch : > > > > Yes. Attached.. > > Today I read about the existence of the "git bisect" function and if I > have not done anything wrong the "bad commit" which lead to this > regression is ddbe503203855939946430e39bae58de11b70b69. > Perhaps this can help you. Interesting, I was about to ask you to do a bisection ;) So the hash value of ::1 was changed, and it has bad effect on your machine... Could it be hash collision and an old bug being uncovered ? Could you trace inet6_addr_hash() a bit ? diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index d7c56f8..096c04c 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -580,7 +580,10 @@ ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp) static u32 inet6_addr_hash(const struct in6_addr *addr) { - return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT); + u32 res = hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT); + + pr_err("inet6_addr_hash(%pi6) %u\n", addr, res); + return res; } /* On success it returns ifp with increased reference count */