From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754578AbZKWSU2 (ORCPT ); Mon, 23 Nov 2009 13:20:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754301AbZKWSU1 (ORCPT ); Mon, 23 Nov 2009 13:20:27 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:55387 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753758AbZKWSU0 (ORCPT ); Mon, 23 Nov 2009 13:20:26 -0500 Date: Mon, 23 Nov 2009 13:20:26 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Jan Kara cc: tmhikaru@gmail.com, , , Jens Axboe , , Subject: Re: Weird I/O errors with USB hard drive not remounting filesystem readonly In-Reply-To: <20091123160914.GG15679@duck.suse.cz> 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 On Mon, 23 Nov 2009, Jan Kara wrote: > On Mon 23-11-09 10:06:03, Alan Stern wrote: > > On Mon, 23 Nov 2009, Jan Kara wrote: > > > > > Yeah, from what you write, it looks like USB enclosure is at fault (or it > > > could still be your USB controller but I doubt it). It's still a bit > > > bothering that the error reported by the drive was not properly propagated > > > up to VFS. Either it's some block layer retry/ignore magic that I missed or > > > we ignore errors from block layer in some place. > > > > Is there any interest in tracking this down? It's not hard to find out > > what low-level errors are being reported and to generate them on demand > > with an emulated USB disk drive. > Well, if you could provide me with the patch, I could try to track down > why the errors aren't propagated... It would be interesting because if it's > not some retry logic in block layer, it's a bug in VFS ;). I can't provide a patch without first knowing what the errors are. The way to find out is to use usbmon. See Documentation/usb/usbmon.txt for instructions. Alan Stern From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Stern Subject: Re: Weird I/O errors with USB hard drive not remounting filesystem readonly Date: Mon, 23 Nov 2009 13:20:26 -0500 (EST) Message-ID: References: <20091123160914.GG15679@duck.suse.cz> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <20091123160914.GG15679@duck.suse.cz> Sender: linux-ext4-owner@vger.kernel.org To: Jan Kara Cc: tmhikaru@gmail.com, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Jens Axboe , linux-scsi@vger.kernel.org, linux-ext4@vger.kernel.org List-Id: linux-scsi@vger.kernel.org On Mon, 23 Nov 2009, Jan Kara wrote: > On Mon 23-11-09 10:06:03, Alan Stern wrote: > > On Mon, 23 Nov 2009, Jan Kara wrote: > > > > > Yeah, from what you write, it looks like USB enclosure is at fault (or it > > > could still be your USB controller but I doubt it). It's still a bit > > > bothering that the error reported by the drive was not properly propagated > > > up to VFS. Either it's some block layer retry/ignore magic that I missed or > > > we ignore errors from block layer in some place. > > > > Is there any interest in tracking this down? It's not hard to find out > > what low-level errors are being reported and to generate them on demand > > with an emulated USB disk drive. > Well, if you could provide me with the patch, I could try to track down > why the errors aren't propagated... It would be interesting because if it's > not some retry logic in block layer, it's a bug in VFS ;). I can't provide a patch without first knowing what the errors are. The way to find out is to use usbmon. See Documentation/usb/usbmon.txt for instructions. Alan Stern