Comment 3 for bug 352197

I've had the chance to further examine this bug on my box. I've found
some things that could even make the bug report not applicable, but
i'd like to ask for advice on further testing:

1.- the problem is not exclusive to the kernel versions mentioned
above, it just hadn't appeared before on the ones marked ok. I have
experienced the same problem with all tested kernels from 2.6.27-7 and
above.

2.- i have experienced the same problem with kubuntu hardy, intrepid
and jaunty beta install disks, as well as debian lenny.

3.- the problem is completely erratic. sometimes it appears at boot,
sometimes it appears on x startup, sometimes only after a few minutes
after the session login. It seems to be related to high disk IO, but i
could not be certain of this, ie i don't know if the problem appears
with the machine "idle".

4.- but most important of all, i have solved it, apparently:
blacklisting ahci in /etc/modprobe.d/blacklist makes the problem go
away, by forcing libata to use the ata_piix driver for all drives (im
sure there must be a more elegant way of doing this, but after
googling for days on "how to disable ahci" i gave up and just
blacklisted the module to test it).

Now, the strange part is that this configuration should be properly
supported by ahci, as the ICH6M controller is thoroughly tested, and
the Hitachi disk that was causing problems is not particularly
esotheric... but i wouldn't know how to test this further, much less
change ahci config params to see if i can get this drive on this
controller to work (if theres any params that could make the disk
behave).

In any case, the bug (?) seems to be located in the AHCI module, and
it seems to affect this HW configuration only, so i don't know if it
makes any sense keepin it open.

I'm willing to try anything suggested if it helps to isolate the issue.

thanks for your time!

On Mon, Apr 6, 2009 at 1:35 PM, Leann Ogasawara
<email address hidden> wrote:
> ** Tags added: intrepid regression-release
>
> --
> ata timeout exception with linux 2.6.28-11
> https://bugs.launchpad.net/bugs/352197
> You received this bug notification because you are a direct subscriber
> of the bug.
>

--
entia non sunt multiplicanda praeter necessitatem