Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755985AbZJKOqN (ORCPT ); Sun, 11 Oct 2009 10:46:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754779AbZJKOqL (ORCPT ); Sun, 11 Oct 2009 10:46:11 -0400 Received: from netrider.rowland.org ([192.131.102.5]:42949 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754259AbZJKOqK (ORCPT ); Sun, 11 Oct 2009 10:46:10 -0400 Date: Sun, 11 Oct 2009 10:45:33 -0400 (EDT) From: Alan Stern X-X-Sender: stern@netrider.rowland.org To: Benjamin Herrenschmidt cc: Josua Dietze , Ben Efros , fangxiaozhi , Greg KH , Kernel development list , USB list , Hugh Blemings Subject: Re: USB serial regression 2.6.31.1 -> 2.6.31.2 In-Reply-To: <1255213021.2192.9.camel@pasglop> 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: 3874 Lines: 66 On Sun, 11 Oct 2009, Benjamin Herrenschmidt wrote: > On Sun, 2009-10-11 at 08:20 +1100, Benjamin Herrenschmidt wrote: > > > Yes, that works, you can see the ttyUSBx ports showing up. It looks like > > it may just be the resets coming from usb-storage that are breaking > > things. > > Ok so I did a quick hack to usb-storage, basically put the block that > tests for the response size and sets USB_FL_SANE_SENSE into an #if 0 : > Now, the result in the dmesg log is : > > Oct 11 09:04:05 pasglop kernel: [ 52.916100] usb 4-1: new full speed USB device using uhci_hcd and address 2 > Oct 11 09:04:05 pasglop kernel: [ 53.076402] usb 4-1: configuration #1 chosen from 1 choice > Oct 11 09:04:06 pasglop kernel: [ 53.104090] Initializing USB Mass Storage driver... > Oct 11 09:04:06 pasglop kernel: [ 53.105405] scsi2 : SCSI emulation for USB Mass Storage devices > Oct 11 09:04:06 pasglop kernel: [ 53.105585] usbcore: registered new interface driver usb-storage > Oct 11 09:04:06 pasglop kernel: [ 53.105589] USB Mass Storage support registered. > Oct 11 09:04:06 pasglop kernel: [ 53.107164] usb-storage: device found at 2 > Oct 11 09:04:06 pasglop kernel: [ 53.107167] usb-storage: waiting for device to settle before scanning > Oct 11 09:04:06 pasglop kernel: [ 53.224104] usb 4-1: USB disconnect, address 2 > Oct 11 09:04:06 pasglop kernel: [ 53.960100] usb 4-1: new full speed USB device using uhci_hcd and address 3 > Oct 11 09:04:11 pasglop kernel: [ 54.121941] usb 4-1: configuration #1 chosen from 1 choice > Oct 11 09:04:11 pasglop kernel: [ 54.140861] scsi6 : SCSI emulation for USB Mass Storage devices > Oct 11 09:04:11 pasglop kernel: [ 54.143007] usb-storage: device found at 3 > Oct 11 09:04:11 pasglop kernel: [ 54.143010] usb-storage: waiting for device to settle before scanning > Oct 11 09:04:11 pasglop kernel: [ 59.141422] usb-storage: device scan complete > Oct 11 09:04:11 pasglop kernel: [ 59.144370] scsi 6:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2 > Oct 11 09:04:11 pasglop kernel: [ 59.147379] scsi 6:0:0:1: Direct-Access HUAWEI SD Storage 2.31 PQ: 0 ANSI: 2 > Oct 11 09:04:11 pasglop kernel: [ 59.169383] sr1: scsi-1 drive > > At which point nothing happens for a while (and no serial stuff shows up). > > If I yank the device, I then see: > > Oct 11 09:05:28 pasglop kernel: [ 59.169494] sr 6:0:0:0: Attached scsi CD-ROM sr1 > Oct 11 09:05:28 pasglop kernel: [ 59.169563] sr 6:0:0:0: Attached scsi generic sg2 type 5 > Oct 11 09:05:28 pasglop kernel: [ 59.169668] sd 6:0:0:1: Attached scsi generic sg3 type 0 > Oct 11 09:05:28 pasglop kernel: [ 59.227809] sd 6:0:0:1: [sdb] Attached SCSI removable disk > Oct 11 09:05:28 pasglop kernel: [ 71.048322] ISO 9660 Extensions: Microsoft Joliet Level 1 > Oct 11 09:05:28 pasglop kernel: [ 71.057316] ISOFS: changing to secondary root > Oct 11 09:05:28 pasglop kernel: [ 128.369159] usb 4-1: USB disconnect, address 3 > Oct 11 09:05:28 pasglop kernel: [ 128.429675] scsi 6:0:0:0: rejecting I/O to dead device The printk timestamps indicate that the first four lines above happened before you unplugged the device. Maybe the first six. But evidently the syslogd process was blocked. > > However, if I put it back in later on ... it works. The storage shows up > and the modem too. > > Weird. I'll have to reboot to try to reproduce with usbmon logging. You might have to get a stack trace (Alt-SysRq-T) as well. It sounds like something important got hung up somewhere. Perhaps the usb-serial modules couldn't be loaded for that reason. 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/