On Mon, Jan 17, 2011 at 02:26:23PM +0100, Tejun Heo wrote:

Hello,

Hi (sorry that got cut out of my original message :) ).

On Sun, Jan 16, 2011 at 08:39:50AM -0800, Marc MERLIN wrote:

quoted

Anyway, the problem happens with both drives that I manually spin down and
drives that spin down on their own. I think it's not actually a 'real',
error but more an issue where drives cannot answer some SMART error when
they are spun down.

It could be that the drives need to spin up to answer the smart
command and the timeout on the smart commands is a bit too short for
that to happen.  Forcing a disk access before issuing the smart
command could work around the problem.

 
Right, although the idea is of course to keep the drives spun down :)
I haven't been able to find which SMART call is causing those errors yet.
Does cmd b0/d8:00:00:4f:c2/00:00:00:00:00/00 translate to anything useful?

quoted

That said, is it normal/expected for the PMP code to do a full bus reset
because of a SMART command that couldn't go through?

Yeah, after a timeout, the driver doesn't know what state the
controller / PMP / devices are in, so it's kind of forced to do full
reset.

Fair enough. I guess it's one of the downsides of PMP.

Thanks for the answer,
Marc
-- 
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems & security ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/