From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [linux-usb-devel] Re: USB storage problems on OHCI.. Date: 03 Oct 2003 10:05:52 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1065193559.1887.52.camel@mulgrave> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from nat9.steeleye.com ([65.114.3.137]:23814 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S263756AbTJCPIY (ORCPT ); Fri, 3 Oct 2003 11:08:24 -0400 In-Reply-To: List-Id: linux-scsi@vger.kernel.org To: Alan Stern Cc: Linus Torvalds , Ruud Linders , Patrick Mansfield , Christoph Hellwig , Matthew Dharm , David Brownell , Greg KH , USB development list , SCSI development list , Andries.Brouwer@cwi.nl On Fri, 2003-10-03 at 09:18, Alan Stern wrote: > There haven't been any replies to my suggestion from a week ago > > http://marc.theaimsgroup.com/?l=linux-scsi&m=106462295800726&w=2 > > for a way to resolve the mode-sense page 8 problem. One way or another, I > wish somebody would do _something_ about this, particularly before > 2.6.0-final comes out. Well, the patch isn't quite correct because if it's not going to probe the cache it should set up a write through cache (or disabled cache) as the default. Patrick's patch http://marc.theaimsgroup.com/?l=linux-scsi&m=106366112221507 Does get this right. But my principle objection, as I've stated before, is that it isn't true that we don't need to manage the caches of hot pluggable devices, fibre channel being the counter example. Even for devices whose model is always forced remove, knowing the cache type is valuable information (especially as writeback cache type would be a rather grave error). The reason not to try to read the cache type for USB is that some of the devices barf on receiving the command. These type of devices are the ones we don't want to make any attempt to manage the cache for, and I'd like the flag name we settle on to reflect this. However, if there's no further objections on the naming front, I'll put Patrick's patch into the SCSI repository. James