Date: Wed, 02 Jan 2008 18:27:00 -0600
From: Robert Hancock <hancockr@shaw.ca>
Subject: Re: sata_nv + ADMA + Samsung disk problem
In-reply-to: <477B3571.6080500@gmail.com>
To: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>, Gabor Gombas <gombasg@sztaki.hu>,
       linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org,
       kluo@nvidia.com, AMartin@nvidia.com, pchen@nvidia.com
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 <477B0CFD.1030603@shaw.ca> <477B10F2.9000107@shaw.ca>
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Tejun Heo wrote:
> 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.

Last I heard, NVIDIA management gave the thumbs down to any more NDAs 
for ADMA documentation. It would be nice if they would reconsider. 
Apparently Jeff does have the docs, though..

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

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