From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [PATCH 0/3] scsi: usb-storage: hide errors for five devices Date: Tue, 15 May 2012 08:35:39 -0700 Message-ID: <20120515153539.GA25206@kroah.com> References: <1336491453.1933.67.camel@x61.thuisdomein> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:65135 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965262Ab2EOPfp (ORCPT ); Tue, 15 May 2012 11:35:45 -0400 Received: by pbbrp8 with SMTP id rp8so7673875pbb.19 for ; Tue, 15 May 2012 08:35:45 -0700 (PDT) Content-Disposition: inline In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Alan Stern Cc: Paul Bolle , "James E.J. Bottomley" , Matthew Dharm , linux-scsi@vger.kernel.org, usb-storage@lists.one-eyed-alien.net, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org On Tue, May 08, 2012 at 01:03:17PM -0400, Alan Stern wrote: > On Tue, 8 May 2012, Paul Bolle wrote: > > > On Tue, 2012-05-08 at 10:02 -0400, Alan Stern wrote: > > > On Tue, 8 May 2012, Paul Bolle wrote: > > > > 1) These patches try to hide those errors by: > > > > - downgrading one error to a notice; and > > > > > > That's a reasonable thing to do, IMO. > > > > > > > - setting the NO_WP_DETECT quirk for these five devices. > > > > > > But that isn't. These quirks are intended for devices that crash when > > > they receive the command in question. > > > > Yes, these USB memory sticks don't crash. (They actually seem to work > > just fine, something that I perhaps should have emphasized in the commit > > descriptions.) > > > > > They aren't meant to suppress sending commands to devices that can > > > properly reject them. > > > > Even the sticks that hit "bad_sense" (in sd_read_cache_type(), which I > > forgot to mention in the comment descriptions)? Is that not as severe as > > it suggests? > > It means that the device either doesn't support the MODE SENSE command > or it returned useless data. As a result, we will assume it has a > write-through cache when it might not. > > For memory sticks this doesn't matter. For other devices it might be > more important (although anything with a working cache should not hit > this error case). > > > Of course, an easy way out would be to downgrade both the "Asking for > > cache data failed" and the "No Caching mode page present" errors to > > notices. But the SCSI people might disagree with that approach. > > Well, let's see what they say. What ever happened here, are these 3 patches acceptable, or do they need to be reworked or something else? thanks, greg k-h