From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263124AbVHEUQE (ORCPT ); Fri, 5 Aug 2005 16:16:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263118AbVHEUOA (ORCPT ); Fri, 5 Aug 2005 16:14:00 -0400 Received: from waste.org ([216.27.176.166]:2013 "EHLO waste.org") by vger.kernel.org with ESMTP id S263107AbVHEUMV (ORCPT ); Fri, 5 Aug 2005 16:12:21 -0400 Date: Fri, 5 Aug 2005 13:12:16 -0700 From: Matt Mackall To: Andi Kleen Cc: John B?ckstrand , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: lockups with netconsole on e1000 on media insertion Message-ID: <20050805201215.GG7425@waste.org> References: <42F347D2.7000207@home.se.suse.lists.linux.kernel> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 05, 2005 at 01:45:55PM +0200, Andi Kleen wrote: > John B?ckstrand writes: > > > I've been trying to hunt down a hard lockup issue with some hardware > > of mine, but I've possibly hit a kernel bug instead. When using > > netconsole on my e1000, if I unplug the cable and then re-plug it, the > > machine locks up hard. It manages to print the "link up" message on > > the screen, but nothing after that. Now, I wonder if this is supposed > > to be so? I tried this on 4 different configurations, 2.6.13-rc5 and > > 2.6.12 with and without "noapic acpi=off", same result on all of > > them. I've tried with 1 and 3 other NICs in the machine at the same > > time. > > I ran into the same problem some time ago on e1000. The problem was > that if the link doesn't come up netconsole ends up waiting forever > for it. I still don't like this fix. Yes, you're right, it should eventually give up. But here it gives up way too easily - 5 could easily translate to 5 microseconds. This is analogous to giving up on serial transmit if CTS is down for 5 loops. I'd be much happier if there were some udelay or the like in here so that we're not giving up on such a short timeframe. -- Mathematics is the supreme nostalgia of our time.