From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc MERLIN Subject: Re: PMP SMART error recovery and failure code decoding help Date: Mon, 17 Jan 2011 09:29:24 -0800 Message-ID: <20110117172924.GE27342@merlins.org> References: <20110116163950.GA691@merlins.org> <20110117132623.GD27123@htj.dyndns.org> <20110117164340.GD27342@merlins.org> <20110117171209.GH27123@htj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from magic.merlins.org ([209.81.13.136]:60575 "EHLO mail1.merlins.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753386Ab1AQR3Z (ORCPT ); Mon, 17 Jan 2011 12:29:25 -0500 Content-Disposition: inline In-Reply-To: <20110117171209.GH27123@htj.dyndns.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: linux-ide@vger.kernel.org On Mon, Jan 17, 2011 at 06:12:09PM +0100, Tejun Heo wrote: > Hello, > > On Mon, Jan 17, 2011 at 08:43:40AM -0800, Marc MERLIN wrote: > > > It could be that the drives need to spin up to answer the smart > > > command and the timeout on the smart commands is a bit too short for > > > that to happen. Forcing a disk access before issuing the smart > > > command could work around the problem. > > > > Right, although the idea is of course to keep the drives spun down :) > > I haven't been able to find which SMART call is causing those errors yet. > > Does cmd b0/d8:00:00:4f:c2/00:00:00:00:00/00 translate to anything useful? > > That's SMART ENABLE OPERATIONS. It turns on SMART. Haha, ok, not as useful as I thought :) > > > > That said, is it normal/expected for the PMP code to do a full bus reset > > > > because of a SMART command that couldn't go through? > > > > > > Yeah, after a timeout, the driver doesn't know what state the > > > controller / PMP / devices are in, so it's kind of forced to do full > > > reset. > > > > Fair enough. I guess it's one of the downsides of PMP. > > The device would still be reset even if it's attached directly. The > only different is that everything under PMP is reset together instead > of individual ones. That's absolutely correct. I was kind of trying to avoid unnecessary full PMP resets: they always make me nervous with software raid on top, but so far no real disasters have happened :) Thanks for your answers, Marc -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems & security .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/