From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [BUG] Kernel recieves DNS reply, but doesn't deliver it to a waiting application Date: Mon, 04 Feb 2013 07:21:07 -0800 Message-ID: <1359991267.30177.143.camel@edumazet-glaptop> References: <20121003232548.eb6b6b22.bircoph@gmail.com> <20121013163639.87abca00.bircoph@gmail.com> <1350135860.21172.14606.camel@edumazet-glaptop> <20121014031119.a60263d6.bircoph@gmail.com> <20121021032543.09d1844f.bircoph@gmail.com> <1350823941.13333.2167.camel@edumazet-glaptop> <20121022073636.98462bc6.bircoph@gmail.com> <1350888489.8609.322.camel@edumazet-glaptop> <20121023012759.ca7f91d6.bircoph@gmail.com> <20121212122716.1e71f644.bircoph@gmail.com> <20121223150627.d7ebcf6a.bircoph@gmail.com> <1356718263.21409.430.camel@edumazet-glaptop> <20130116203644.8eb2a16f.bircoph@gmail.com> <20130204173932.bad780bc.bircoph@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Andrew Savchenko Return-path: Received: from mail-pa0-f51.google.com ([209.85.220.51]:49240 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753506Ab3BDPVK (ORCPT ); Mon, 4 Feb 2013 10:21:10 -0500 Received: by mail-pa0-f51.google.com with SMTP id hz1so2440173pad.38 for ; Mon, 04 Feb 2013 07:21:09 -0800 (PST) In-Reply-To: <20130204173932.bad780bc.bircoph@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 2013-02-04 at 17:39 +0400, Andrew Savchenko wrote: > With 16-days uptime system works fine. > > Also I was able to reproduce this bug on another box: an embedded > system running openwrt with 3.7.5 kernel with openl2tpd client and > dnsmasq server. Due to limited memory resources this bug happened to > be easily reproducible: several thousands of dns queries were > sufficient to reproduce this bug. Full debug on embedded box was not > possible due to constrained resources, but bug appearance was the same > and /proc/net/udp is apparently broken (see attached log). > > I applied your patch on openwrt's 3.7.5 kernel and it fixed the bug > on this box too. > > So we've found a solution and I'm looking forward for it in the main > kernel :) Thanks a lot for testing, I'll send the official patch asap.