From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH #upstream] libata: blacklist NCQ on Seagate Barracuda ST380817AS Date: Thu, 04 Oct 2007 21:32:55 +0900 Message-ID: <4704DD77.6070609@gmail.com> References: <20071004020656.GA12186@htj.dyndns.org> <20071004125436.1ae8dbe8@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from el-out-1112.google.com ([209.85.162.176]:59208 "EHLO el-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756432AbXJDMdD (ORCPT ); Thu, 4 Oct 2007 08:33:03 -0400 Received: by el-out-1112.google.com with SMTP id v27so30615ele for ; Thu, 04 Oct 2007 05:33:02 -0700 (PDT) In-Reply-To: <20071004125436.1ae8dbe8@the-village.bc.nu> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: Jeff Garzik , linux-ide@vger.kernel.org, ornati@fastwebnet.it Alan Cox wrote: > On Thu, 4 Oct 2007 11:06:56 +0900 > Tejun Heo wrote: > >> From: Paolo Ornati >> >> Seagate Barracuda ST380817AS has troubles with NCQ. For example, >> unpacking a tarball on an XFS filesystem gives this: >> >> ata1.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x2 frozen >> ata1.00: cmd 61/40:00:29:a3:98/00:00:00:00:00/40 tag 0 cdb 0x0 data 32768 out >> res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout) > > Looking at this and our NCQ code I don't see any provision for drive > unfairness in our code. If we continue to issue commands to the drive I'm > not seeing where we guarantee a given command will ever complete rather > than being deferred forever by a dumb drive - which some SCSI drives also > will do... After several such timeouts, libata will turn off NCQ which should solve the problem. -- tejun