Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757646Ab0GWVvJ (ORCPT ); Fri, 23 Jul 2010 17:51:09 -0400 Received: from einhorn.in-berlin.de ([192.109.42.8]:42617 "EHLO einhorn.in-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756145Ab0GWVvG (ORCPT ); Fri, 23 Jul 2010 17:51:06 -0400 X-Envelope-From: stefanr@s5r6.in-berlin.de Message-ID: <4C4A0EB5.4020405@s5r6.in-berlin.de> Date: Fri, 23 Jul 2010 23:50:45 +0200 From: Stefan Richter User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.8.1.23) Gecko/20100627 SeaMonkey/1.1.18 MIME-Version: 1.0 To: Martin Mokrejs CC: Jay Fenlason , LKML , linux1394-devel@lists.sourceforge.net Subject: Re: 2.6.35-rc6 to 2.6.32.16: JuJu firewire issues References: <4C49A291.20001@ribosome.natur.cuni.cz> <20100723180807.GA32319@redhat.com> <4C49E1A2.7050606@ribosome.natur.cuni.cz> <20100723192646.GB32319@redhat.com> <4C49F955.1040308@ribosome.natur.cuni.cz> <4C4A0CAF.9060308@s5r6.in-berlin.de> In-Reply-To: <4C4A0CAF.9060308@s5r6.in-berlin.de> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1460 Lines: 30 Stefan Richter wrote: > Your dmesg shows multiple bus resets and one of the three nodes > disappearing from the bus from time to time. This points to a probelm > at the physical layer (i.e. highly unreliable hardware) which > fundamentally cannot be solved by software. PS: If you want, you can for example run the small utility "firecontrol" (requires libraw1394) in a console while you have the FireWire disk attached. Firecontrol will show all bus resets that happen as well as how many nodes are present on the bus after each reset. During usage of a FireWire disk, there should be only about two or so bus resets early on when the disk is plugged in, but then not anymore. The drivers do handle subsequent bus resets (firewire-sbp2 + firewire-core much better than sbp2 + ieee1394, obviously) but they cannot do much if very frequent bus resets happen and the target node even disappears from the bus due to electrical problems or whatever reasons. According to your dmesg, I expect firecontrol to show series of resets, some of them with a node going away and coming back. The most likely cause for that is buggy or defective hardware. -- Stefan Richter -=====-==-=- -=== =-=== http://arcgraph.de/sr/ -- 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/