Re: sata_nv + ADMA + Samsung disk problem

From: Robert Hancock
Date: Wed Jan 02 2008 - 19:28:15 EST


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@xxxxxxxxxxxxx
Home Page: http://www.roberthancock.com/

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/