Re: [Kgdb-bugreport] [PATCH] Kill kgdb_serial

[Tom Rini <trini@kernel.crashing.org>]

On Tue, Mar 02, 2004 at 04:36:11PM -0800, George Anzinger wrote:
> Tom Rini wrote:
> >Regardless, it's not that we offer (nor does the -mm version, from what
> >I read of it) eth or serial at any point, it simply allows for serial to
> >be used and a switchover to eth.  And if kgdb is attached at the time,
> >it's a 'fun' gdb session (or at least is was when I was trying it out in
> >-mm and then in my own version).
> 
> I am not really suggesting a live switch capability, more like something 
> that is set a boot time.

That's still not, AFAICT, what's offered in -mm or kgdb.sf.net.

> >The real problem is that you start getting quite complex when you allow
> >for a system to be kgdb eth, or 8250, or some arch serial driver, or
> >some other I/O driver, and so on.  PPC has 3, and I don't see it getting
> >smaller from there.
> 
> I had imagined that it would be rather like a file system.  The stub would 
> pass (or it could be a global if you prefer) the index to use into an array 
> of interface structures.  Something like:
> 
> struct kgdb_interface {
> 	void (*kgdb_in)(*char)
> 	:
> 	:
> }
> 
> struct kgdb_interface kgdb_io_array[N];

And how do you pick a default?

> >And with both of those points, I don't think it's worth the trouble that
> >point 2 is, given the limitations of point 1.
> 
> I imagine that I would like this.  I would use the eth interface until 
> required to use the serial.  I would rather not have to rebuild the kernel 
> to do this....

Then you're talking about live switching again, or some sort of control
from userland.

-- 
Tom Rini
http://gate.crashing.org/~trini/