Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757197Ab1DHOZM (ORCPT ); Fri, 8 Apr 2011 10:25:12 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:33139 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1757040Ab1DHOZK (ORCPT ); Fri, 8 Apr 2011 10:25:10 -0400 Date: Fri, 8 Apr 2011 10:25:08 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Zdenek Kabelac cc: USB list , Linux Kernel Mailing List Subject: Re: Endless loop with "detected XactErr" In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1671 Lines: 47 On Thu, 7 Apr 2011, Zdenek Kabelac wrote: > Hi > > I've been trying to track some resume error with Intel GPU - and > notice a couple problems related to resume of my Lenovo T61. > Laptop has been docked - and suspend/resume has been performed without > 'undocking' laptop. > > After several iterations of suspend/resume - I've got this endless > printing loop with this line on console display: > > ehci_hcd 0000:00:1a.7: detected XactErr len 0/4 retry 1 > > Just with changing last number - I've got only one such line on serial console. > By looking into "drivers/usb/host/ehci-q.c" - there seems to be > endless goto loop. It isn't endless. You didn't notice the test against QH_XACTERR_MAX. > From the log it looks like my USB mouse connected to docking station > was the source of problem. > (Maybe a movement ??) This particular error message indicates a hardware problem in the USB signals. A bad contact, a bad cable, a device failure -- something like that. > Here is the trace from last resume: > [ 473.873802] ACPI: \_SB_.GDCK - undocking > [ 473.897678] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0010 > [ 473.904809] ehci_hcd 0000:00:1a.7: detected XactErr len 0/4 retry 1 And presumably additional lines containing similar messages. There's no real reason for them ever to stop, since they are only debugging messages. If you turn off CONFIG_USB_DEBUG you'll never see tham. Alan Stern -- 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/