Reset Problem with SATA Port Multiplier

[Bob Bawn]

On Thu, Jul 25, 2013, Dieter BSD <dieterbsd at gmail.com> wrote:

> Sounds like FreeBSD is doing something bad to the pm, which Linux isn't
> doing. Perhaps log the commands the OS sends to the controller (over the
> network to a 2nd machine, or to a local disk not on a pm) and compare
> BSD to Linux?  Perhaps start logging when you get the first timeout, to
> save hours of commands to wade through.

Yes, that occurred to me. I was hoping to avoid learning how to build
kernels with debug messages but I suppose it's a good skill to have. :-)

> Alternately you could stare at the driver sources until enlightenment
> occurs.

I did a little of this and superficially it does seem like there could
be differences between FreeBSD and Linux in the treatment of the
mysterious 6th port (SEMB) on the 5-port multiplier. Hopefully, the
logging you suggest will clarify the situation.

Thanks for your help.