Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751018AbXBCV1f (ORCPT ); Sat, 3 Feb 2007 16:27:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750860AbXBCV1f (ORCPT ); Sat, 3 Feb 2007 16:27:35 -0500 Received: from vms040pub.verizon.net ([206.46.252.40]:49644 "EHLO vms040pub.verizon.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750979AbXBCV1d (ORCPT ); Sat, 3 Feb 2007 16:27:33 -0500 Date: Sat, 03 Feb 2007 13:26:12 -0800 From: Auke Kok Subject: Re: 2.6.20-rc7: known regressions (v2) (part 1) In-reply-to: <093c01c747d6$45f9a2f0$84163e05@kroptech.com> To: Adam Kropelin Cc: Auke Kok , "Eric W. Biederman" , Adrian Bunk , Linus Torvalds , Andrew Morton , Linux Kernel Mailing List , jgarzik@pobox.com, alan@lxorguk.ukuu.org.uk, Allen Parker , jesse.brandeburg@intel.com, gregkh@suse.de, linux-pci@atrey.karlin.mff.cuni.cz, netdev@vger.kernel.org Message-id: <45C4FDF4.4060002@intel.com> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit References: <20070203004447.GJ3754@stusta.de> <45C42669.2010105@intel.com> <089b01c747be$0ca22620$84163e05@kroptech.com> <45C4F3F1.6060500@intel.com> <093c01c747d6$45f9a2f0$84163e05@kroptech.com> User-Agent: Mail/News 1.5.0.9 (X11/20061228) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1814 Lines: 41 Adam Kropelin wrote: > Auke Kok wrote: >> Adam Kropelin wrote: >>> I've never had this device work 100% with MSI on any kernel version >>> I've tested so far. But I'm not the original reporter of the >>> problem, and I believe for him it was a true regression where a >>> previous kernel wored correctly. >> maybe I've been unclear, but here's how e1000 detects link changes: >> >> 1) by checking every 2 seconds in the watchdog by reading PHY >> registers > > That would explain why I see link status changes but 0 interrupt count > in /proc/interrupts. However, on >= 2.6.19 the link state never changes. > Ever. It's always down. On <= 2.6.18 the link state does change but with > 0 interupt count. > >> 2) by receiving an interrupt from the NIC with the LSI bit >> in the interrupt control register >> >> if the link is down to start with, the watchdog will obviously spot a >> 'link up' change since it doesn't use any interrupts. > > This does not seem to work on 2.6.19+. Unless the watchdog interval is > tens of minutes. I've waited at least 5 minutes and link never went up. that's explained by a driver change that did that. Since at initialization we're basically waiting for a link change to tell the stack that we're up, we decided to change the order to have the hardware fire an LSI interrupt to trigger a watchdog run. So no interrupts would immediately explain why the watchdog never runs. That's nothing to worry about for this problem, as soon as interrupts are seen in /proc/interrupts this all starts working for e1000. Cheers, Auke - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/