On Apr 30, 2012, at 2:03 PM, Cameron Kaiser wrote:
    [...] because USB is
 one-way 
 Since when? 
 
 I think David is referring to its polled nature. 
 
Yes, I suppose "asymmetric" would have been a better term.  It's
not peer-to-peer like serial ports or 1394 are, which is what would
make it nearly useless for kernel debug; that's before you get to
issues of protocol stack, which 1394 gets away with by using DMA
on the controller, which is questionable from a security standpoint
but great for kernel debug.
- Dave