From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750893AbVIWLlX (ORCPT ); Fri, 23 Sep 2005 07:41:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750897AbVIWLlX (ORCPT ); Fri, 23 Sep 2005 07:41:23 -0400 Received: from clock-tower.bc.nu ([81.2.110.250]:27037 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1750892AbVIWLlX (ORCPT ); Fri, 23 Sep 2005 07:41:23 -0400 Subject: Re: Libata for parallel ATA controllers From: Alan Cox To: Mark Lord Cc: linux-kernel@vger.kernel.org In-Reply-To: <4333674D.3070502@rtr.ca> References: <1127408726.18840.126.camel@localhost.localdomain> <4333674D.3070502@rtr.ca> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Fri, 23 Sep 2005 13:07:56 +0100 Message-Id: <1127477276.5561.15.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Iau, 2005-09-22 at 22:24 -0400, Mark Lord wrote: > built-in error-handling or recovery mechanisms yet. If a drive > gets into a "reset me to recover" state, then libata just might > require a reboot to recover, whereas the IDE subsystem will usually > try a reset operation at some point. Or crash. > Not a problem with modern, mostly bug-free hardware (eg. most SATA), > but this could be an issue for some PATA interfaces. The basic error handling in the libata code seems to work as well when I tested it, if not better because the old PATA code hangs the box on SMP or pre-empt if you get a DMA timeout and cable changedown due to locking flaws and also issues an immediate idle in error recovery which seems to crash some drives for good. What doesn't work at all is failed cable detect - the speed change down support simply isn't in libata yet and that turns a downspeed change for poor cables or cable misdetect into a hang.