From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: [Bugme-new] [Bug 8132] New: pptp server lockup in ppp_asynctty_receive() Date: Fri, 9 Mar 2007 11:21:43 +0100 Message-ID: <20070309102143.GD1662@ff.dom.local> References: <20070308084539.GA2423@ff.dom.local> <01a001c76226$c956b290$9b01a8c0@Empty> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andrew Morton , netdev@vger.kernel.org, "bugme-daemon\@kernel-bugs\.osdl\.org" , Alan Cox To: "Yuriy N\. Shkandybin" Return-path: Received: from mx2.go2.pl ([193.17.41.42]:58088 "EHLO poczta.o2.pl" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2993102AbXCIKRk (ORCPT ); Fri, 9 Mar 2007 05:17:40 -0500 Content-Disposition: inline In-Reply-To: <01a001c76226$c956b290$9b01a8c0@Empty> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, Mar 09, 2007 at 11:40:04AM +0300, Yuriy N. Shkandybin wrote: ... > I already have > CONFIG_PROVE_LOCKING=y > # CONFIG_4KSTACKS is not set > .config is at > http://bugzilla.kernel.org/attachment.cgi?id=10660&action=view > Also all information i've provied was recieved by serial console and it's > not hand writing. Maybe you cut too much (lines before a bug could be meaningful - if there are some secret data - try to mask only them). And there is no real lockdep diagnose, so I wasn't sure. Dump registers at the end looks incomplete (no ESP info), too. So, this all made me think - it's cut because it's from the screen. Very sorry!!! > I've checked logs and right before lockup there is oops in syslog > Mar 5 21:50:44 vpn2 skb_under_panic: text:c02248a2 len:207 put:1 As a matter of fact the first bug is the most interesting and everything after could be only some aftereffect. This skb_under_panic message could change all diagnose: it's not necessarily a locking problem. On the other hand this could be even harder to diagnose than locking... > head:db96e22c data:db96e22b tail:db96e2fa end:db96e82c dev: > Mar 5 21:50:44 vpn2 ------------[ cut here ]------------ Why?! We don't even know if there was some config pending here. > Mar 5 21:50:44 vpn2 kernel BUG at net/core/skbuff.c:112! ... > Another thing - when i`ve changed HZ from 100 too 300 there is no such > lockups for few days. You wrote it had been since several kernel releases, so it shouldn't be the case, but anyway - it would be interesting to check HZ 100 but with clean and more current kernel version e.g. 2.6.21-rc3. Thanks & regards, Jarek P.