From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH 7/9] libata-acpi: improve _GTF execution error handling and reporting Date: Fri, 14 Dec 2007 23:50:23 +0900 Message-ID: <4762982F.2060701@gmail.com> References: <11976129411285-git-send-email-htejun@gmail.com> <11976129433239-git-send-email-htejun@gmail.com> <47628F3A.1060806@rtr.ca> <47629004.4040701@gmail.com> <47629720.4010602@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from rv-out-0910.google.com ([209.85.198.184]:38860 "EHLO rv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753458AbXLNOua (ORCPT ); Fri, 14 Dec 2007 09:50:30 -0500 Received: by rv-out-0910.google.com with SMTP id k20so964854rvb.1 for ; Fri, 14 Dec 2007 06:50:29 -0800 (PST) In-Reply-To: <47629720.4010602@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mark Lord Cc: jeff@garzik.org, hancockr@shaw.ca, linux-ide@vger.kernel.org Mark Lord wrote: > Tejun Heo wrote: >> Mark Lord wrote: >>> Tejun Heo wrote: >>>> As _GTF commands can't transfer data, device error never signals >>>> transfer error. It indicates that the device vetoed the operation, so >>>> it's meaningless to retry. >>> .. >>> >>> The SECURITY commands may pass a data block to the drive, >>> containing the password required to unlock/freeze a drive. >>> I suspect ACPI on many machines will issue such a command, >>> and it does indeed transfer data (512 bytes). >> >> Surprise, ACPI _GTF can't do that. Don't ask me why. :-) > .. > > Then why are we (going to be) filtering those op's (one of your patches) ? Filtered ones are not LOCK / FREEZE LOCK commands which prevent further changes. e.g. SET MAX FREEZE LOCK will prevent further size changes using SET MAX [EXT]. It's bad for three reasons 1. it locks down drive feature without user consent (e.g. can't unlock HPA) 2. it makes debugging difficult by putting drives into different states 3. it just doesn't serve any good. -- tejun