Kevin Sullivan <ksulliva@psc.edu> writes:

>
> Odd.  I built a new (non-generic) kernel from today's sources and the 
> problem seems to have vanished.  The machine is now quite happy with a 
> disconnected serial console.  I'd still be interested in knowing *why* it 
> happened before, though, if anyone has any insights :-)

It's because there was a bug.  B-)

Seriously, there was a bug that could cause the com driver to loop in
the interrupt handler if a line was disconnected while active.  I
fixed this in my recent batch of serial driver changes.