From mboxrd@z Thu Jan 1 00:00:00 1970 From: Albert Lee Subject: Re: libata: CD and dvd devices not recognized Date: Fri, 23 Mar 2007 11:40:36 +0800 Message-ID: <46034C34.5000602@tw.ibm.com> References: <45F873AC.6010204@gmail.com> <200703172107.42107.bzolnier@gmail.com> <45FD0F68.7090207@gmail.com> <200703181610.33714.bzolnier@gmail.com> <45FE7DCC.3000507@ru.mvista.com> <45FEE5EB.9020909@gmail.com> <4600BA1C.7060300@tw.ibm.com> <4600F45C.3000303@gmail.com> <46021CDA.3070807@tw.ibm.com> <20070322123729.14f11b96@lxorguk.ukuu.org.uk> Reply-To: albertl@mail.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from e34.co.us.ibm.com ([32.97.110.152]:36613 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422664AbXCWDkn (ORCPT ); Thu, 22 Mar 2007 23:40:43 -0400 Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e34.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id l2N3ehmi030622 for ; Thu, 22 Mar 2007 23:40:43 -0400 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by westrelay02.boulder.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l2N3eg32064174 for ; Thu, 22 Mar 2007 21:40:42 -0600 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l2N3efBf027546 for ; Thu, 22 Mar 2007 21:40:42 -0600 In-Reply-To: <20070322123729.14f11b96@lxorguk.ukuu.org.uk> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: albertl@mail.com, YUP , Bartlomiej Zolnierkiewicz , linux-ide@vger.kernel.org, Sergei Shtylyov , Jeff Garzik , dougg@torque.net Alan Cox wrote: >>We have two possible solutions here: >>a. Patch Ubuntu, such that the incorrect INQUIRY is fixed. >>b. Patch kernel, such that the AOpen drives are blacklisted. >> Each INQUIRY is inspected for the blacklisted drives. >> If the INQUIRY looks wrong, the INQUIRY is rejected. >> >>I guess a. is the preferred solution... > > > We have two problems here > > #1 Ubuntu got the inquiry command wrong > > #2 Until now we considered "INQUIRY" a safe command for SG_IO passthrough. > > We can't really take INQUIRY out of SG_IO so do we decide its the > hardware vendors problem or do something cleverer in the filters ? > Maybe the SG_IO author has better idea (ccing Doug)? BTW, in addition to the AOpen "INQUIRY with EVPD" problem, we have another imperfect ATAPI drive (TORiSAN) that freezes when "READ >= 128KB". (http://bugzilla.kernel.org/show_bug.cgi?id=6710) We can limit "dev->max_sectors" to workaround the TORiSAN problem. But I don't know whether "dev->max_sectors" also works for SG_IO? If no, some user space application, unaware of the problem, might send a "correct" READ that locks the drive completely. -- albert