From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: sata_nv + ADMA + Samsung disk problem Date: Wed, 02 Jan 2008 15:55:45 +0900 Message-ID: <477B3571.6080500@gmail.com> References: <20070808120804.GB5257@boogie.lpds.sztaki.hu> <20080101164416.GA29574@boogie.lpds.sztaki.hu> <477B0429.7040909@gmail.com> <477B0CFD.1030603@shaw.ca> <477B10F2.9000107@shaw.ca> <477B1233.3090706@gmail.com> <477B2CE4.8070602@garzik.org> <477B318E.4030309@shaw.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 ([209.85.198.187]:62610 "EHLO rv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751210AbYABGzx (ORCPT ); Wed, 2 Jan 2008 01:55:53 -0500 Received: by rv-out-0910.google.com with SMTP id k20so5158751rvb.1 for ; Tue, 01 Jan 2008 22:55:52 -0800 (PST) In-Reply-To: <477B318E.4030309@shaw.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Robert Hancock Cc: Jeff Garzik , Gabor Gombas , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, kluo@nvidia.com, AMartin@nvidia.com, pchen@nvidia.com Robert Hancock wrote: > Jeff Garzik wrote: >> Tejun Heo wrote: >>> Thanks a lot for the detailed explanation. Nvidia ppl, any ideas? >>> FLUSH is used regularly. We really need to fix this. >> >> >> I reiterate my opinion :) ... We should remove ADMA support from >> sata_nv. It's only in a few chips, it's not appearing in any new >> chips, and nasty problems have lingered since ADMA support was >> introduced. >> >> Definitely sounds like we should disable ADMA by default for >> 2.6.24-rc, too. > > I wouldn't agree.. It's only in a few chips (CK804/MCP04), but those > chips are very common in desktop, workstation, even some server > machines. Given the huge number of these chips out there, problem > reports have been quite rare. I agree with Jeff here. Maybe not remove but disable it by default and when enabling warn loudly. NCQ just doesn't enough for its cost when the cost includes erratic behaviors. Only very small fraction of error cases actually make to bugzilla or this mailing list. Nvidia gents, is there anyway (be it NDA or whatever) to get Robert or any of us technical documentation? Thanks. -- tejun