Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756077Ab0LHP5v (ORCPT ); Wed, 8 Dec 2010 10:57:51 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:36405 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756014Ab0LHP5u (ORCPT ); Wed, 8 Dec 2010 10:57:50 -0500 Date: Wed, 8 Dec 2010 10:57:46 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: James Bottomley cc: Greg KH , Luben Tuikov , Matthew Dharm , Linus Torvalds , , , Subject: Re: [PATCH repost 3] [SCSI] Retrieve the Caching mode page In-Reply-To: <1291823012.24312.52.camel@mulgrave.site> 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: 2045 Lines: 48 On Wed, 8 Dec 2010, James Bottomley wrote: > On Wed, 2010-12-08 at 10:16 -0500, Alan Stern wrote: > > On Tue, 7 Dec 2010, James Bottomley wrote: > > > > > Well, not other than I've already said: I think it looks OK, so I > > > marked it for my merge window queue. I'd still rather like USB people > > > to confirm that the original reason why this was done (to prevent device > > > crashes on the mode sense) is no longer an issue > > > > The original reason for adding the skip_ms_page_8 flag still applies. > > To assume it is no longer an issue would not be safe -- there's no > > reason to believe that the buggy devices it was meant for have all been > > retired. > > > > > ... but it's only USB > > > stuff, so suppose I'm OK with finding out in the field. > > > > With USB there's often no other choice. > > So the translation is that there's a possibility it will crash USB > devices but the only way to find out is to release it and see. In the strictest sense, there's always a possibility that any change will crash _some_ device somewhere. In this case I believe the probability is very low. Luben's patch does not change the commands sent to a USB device; it only changes the kernel's interpretation of the data sent back. Unless things are terribly badly broken, this won't hurt. > My problem is that it only takes one bug report from one failing device > (which I'm sure some kind soul will dig out of the attic or wherever > they threw it) for this to be a regression and then I get to revert the > patch ... unless we have a working backup plan? > > I think it's easy to put in and easy to revert ... we'll pick up a bit > of flack if the failing device doesn't appear for some time, but I'm OK > with risking that. IMO the risk is extremely small. 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/