Re: [PATCH] blacklist NCQ on Seagate Barracuda ST380817AS

From: Tejun Heo
Date: Sun Sep 30 2007 - 13:30:58 EST


Mark Lord wrote:
> Jeff Garzik wrote:
>> Paolo Ornati wrote:
>>> I have this problem only with XFS, and even with XFS it goes away
>>> mounting with "nobarrier"...
>>
>> This last is an interesting datapoint.
>>
>> I wonder if libata has a generic problem with NCQ + FLUSH CACHE.
>
> Yeah, that's pretty suspicious. Prior to issuing a FLUSH_CACHE op,
> one must first drain all outstanding NCQ commands (and not issue new ones).
>
> I'm sure the code must *try* to do that, but perhaps there's a bug in
> there?
> Or just another drive bug?

If there was such a bug, the aborted commands list should contain both
FPDMA commands and FLUSH commands. I don't think command filtering
itself is broken. Possibly another quirky firmware but it's strange
that this is the only Seagate drive showing this problem.

Thanks.

--
tejun
-
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/