Re: lan based kgdb

[torvalds@transmeta.com (Linus Torvalds)]

In article <20021115222430.GA1877@tahoe.alcove-fr>,
Stelian Pop  <stelian.pop@fr.alcove.com> wrote:
>	  
>	* the USB stack seems simpler than the net stack + 
>	  (eventualy) pcmcia + network card driver.

What drugs are you on? The USB stack is extremely complex and fragile,
and depends on a lot more working than just about any network driver out
there. We're still debugging basic USB functionality.

Yes, if you're comparing to a full TCP implementation, plain USB serial
lines may be simpler (ignoring for the moment the fact that there isn't
even a standard USB serial line protocol, and they may be going the same
way as the hardware serial lines - the way of the dodo). 

But it should be possible to do a really simple UDP-packets-only thing
for kgdb.  Sure, it may lose packets.  Tough.  Don't debug over a WAN,
and try to keep a clean direct network connection if you are worried
about it.  But we want kernel printk's to be synchronous anyway, without
timeouts etc.

And I suspect you're better off losing packets (very rarely over any
normal local network) if that means that your debugger needs only
minimal support. You can always re-type.

		Linus