Re: libata oops 2.6.11-rc4 yesterdays BK

[Jeff Garzik <jgarzik@pobox.com>]

Andy Warner wrote:
> Brad Campbell wrote:
> 
>>[...]
>>Actually, I'm not sure without the libata dev patch as that removes SMART support, and I'm not 
>>convinced that my smartd polling every 20 minutes does not have something to do with it. All I know 
>>is the older kernel seems to cope. We'll see. 320 minutes left on this rebuild. I expect it will be 
>>done in the morning if all goes according to plan. (With the 2.6.11 kernel it never survived past 
>>about 25% rebuilt)
> 
> 
> Can you find time to try it without smartd active ?
> You report running a uni-processor system, and I have only
> seen PIO problems with (fast) SMP systems in my testing,
> but I am forming the opinion that libata-PIO functions
> are in need of a minor overhaul.
> 
> I have seen issues where port activity monopolised
> data-paths/arbitration inside chipsets such that the
> PIO operations would appear to time out. Since you're
> doing a raid rebuild, perhaps the I/O load is causing
> something similar to occur.

Does the PIO code deviate from the ATA/ATAPI-[4567] host state machine 
somehow?

Or is it just that newer SATA-emulating-PATA chips have trouble with it?

	Jeff