Reset Problem with SATA Port Multiplier

[Dieter BSD]

Bob writes:
> After a few hours of a database-like workload

A faster way to trigger the problem would be useful.

> We're actually more interested in archive type workloads than this
> database workload and we have not observed the problem with an archive
> workload.

So perhaps something about the timing triggers the bug?

Sam writes
> if you have a script or a way to build a kernel to help debug this I will
> run it if you post it here... I have the same issue on a 3 port multiplier
> using -HEAD

Can you share the make and model of this 3 port multiplier?
If it is happening with more than one model of pm, it is more likely
some generic problem, rather than triggering some model-specific quirk/bug.
Has anyone seen this problem with an older OS release? (say 7.x or 8.x?)
If the problem was introduced recently, we might be able to find it
by looking at what changed in the source code. I haven't seen the
problem with 8.2 or earlier.

Looks like a verbose boot will give a little more info.
But I suspect that adding more log(9) statements will be needed.
Unless mav has a better idea?