How is supposed to be protected the units list?

[Matthew Jacob]

On 3/30/2010 9:14 AM, Matthew Jacob wrote:
>  Absolutely. I might also be insane. Working on finding that out.
>> May you please refer precisely to current code snippets (in terms of
>> functions, file, line, etc) in order to better explain this and the
It partly ends up the same as what Alexander found. I like his unit_lock 
patch a bit better.

In terms of the xpt_lock.diff patches for da- I don't think this is a 
good idea as they stand.

This is part of shutdown code, which can be called as part of panic, so 
there is no guarantee about what locks might or might not be held, or 
even whether the list being traversed is intact at all.

The problems that I ran into previously in da won't be fixed really by 
any of this. The problem here for da(4) is that it is scheduling a task 
to run- if the periph is going away, then the task should be cancelled.

Still testing... I'm working on a fault injection case where tons of 
arrival/departure events can be thrown at this.