Re: hsm violation

[Robert Hancock <hancockr@shaw.ca>]

Andrew Morton wrote:
> On Sun, 24 Jun 2007 14:32:22 +0200 Enrico Sardi <enricoss@tiscali.it> wrote:
>> [   61.176000] ata1.00: exception Emask 0x2 SAct 0x2 SErr 0x0 action 0x2 
>> frozen
>> [   61.176000] ata1.00: (spurious completions during NCQ issue=0x0 
>> SAct=0x2 FIS=005040a1:00000004)

..

> 
> It's not obvious (to me) whether this is a driver bug, a hardware bug,
> expected-normal-behaviour or what - those diagnostics (which we get to
> see distressingly frequently) are pretty obscure.

The spurious completions during NCQ error is indicating that the drive 
has indicated it's completed NCQ command tags which weren't outstanding. 
  It's normally a result of a bad NCQ implementation on the drive. 
Technically we can live with it, but it's rather dangerous (if it 
indicates completions for non-outstanding commands, how do we know it 
doesn't indicate completions for actually outstanding commands that 
aren't actually completed yet..)

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