From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: netconsole still hangs Date: Wed, 12 Mar 2008 16:30:13 -0700 Message-ID: <20080312163013.aaf07aa0.akpm@linux-foundation.org> References: <20080312161429.d5b1c67b.akpm@linux-foundation.org> <20080312161637.b082b515.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit To: shemminger@linux-foundation.org, netdev@vger.kernel.org, rjw@sisk.pl Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:45610 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751474AbYCLXa3 (ORCPT ); Wed, 12 Mar 2008 19:30:29 -0400 In-Reply-To: <20080312161637.b082b515.akpm@linux-foundation.org> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 12 Mar 2008 16:16:37 -0700 Andrew Morton wrote: > On Wed, 12 Mar 2008 16:14:29 -0700 > Andrew Morton wrote: > > > > > I thought the recent reverts fixed this, but it seems that it's just become > > a little harder to hit. > > > > I'm seeing netconsole hangs on two x86_64 systems (2-way t61p laptop, 8-way > > server). Both use e1000. > > > > With current mainline on the 8-way, create a printk storm with > > > > while true > > do > > echo t > /proc/sysrq-trigger > > done > > > > and the machine goes tits-up after about five seconds. > > > > whoops, hang on, it's still running. And it's still running! I killed the above loop five minutes ago and nothing new is coming out in `dmesg -c', yet data is still flying out over netconsole. hundreds and hundreds of megabytes. So I'd say that something in netconsole or the console susbsytem has screwed up its buffer indices and it has gone infinite. I don't know whether that's a regression though. OK, that stopped it, so the problem isn't buffering at the receiver. I already knew that, because the ifconfig "TX bytes" counters were going up on the sending side. OK, this time it did hang up. Machine unpingable, no signs of life.