Re: BitKeeper repo for KGDB

[Matt Mackall <mpm@selenic.com>]

On Mon, Feb 09, 2004 at 08:50:13AM -0700, Tom Rini wrote:
> On Sun, Feb 08, 2004 at 07:29:51PM -0600, Matt Mackall wrote:
> > On Fri, Feb 06, 2004 at 04:02:54PM -0700, Tom Rini wrote:

> > >  	if (!netpoll_trap() && len == 8 && !strncmp(msg, "$Hc-1#09", 8))
> > > -		printk(KERN_CRIT "Someone is trying to attach\n");
> > > -//		kgdb_schedule_breakpoint();
> > > +		breakpoint();
> > >  
> > >  	for (i = 0; i < len; i++) {
> > > -		if (msg[i] == 3)	/* Check for ^C? */
> > > -			printk(KERN_CRIT "Someone is trying to ^C?\n");
> > > -//			kgdb_schedule_breakpoint();
> > > +		if (msg[i] == 3)
> > > +			breakpoint();
> > 
> > The kgdb_schedule_breakpoint stuff in -mm didn't just appear to make
> > things more complicated, it is in fact necessary. You cannot
> > reasonably expect to break deep inside the network stack IRQ handler
> > and then send more packets out the same interface. Expect especially
> > nasty results on SMP. It only works for the serial case because that
> > path is a priori known to be lockless.
> 
> Ah, hmm...  I don't suppose there's any way to do this w/o touching
> every arch's do_IRQ, is there?

Probably not. On the other hand, it provides yet more motivation for
an irq handling refactoring in 2.7.

-- 
Matt Mackall : http://www.selenic.com : Linux development and consulting