Re: Device Driver Etiquette

[Matt Fredrickson <creslin@digium.com>]

----- "Arjan van de Ven" <arjan@infradead.org> wrote:
> On Fri, 2007-06-01 at 12:47 -0500, Matthew Fredrickson wrote:
> 
> > My question is this: is there a way to either work around the
> problem I 
> > am seeing with the stack without recompiling the kernel with 8K
> stack 
> > size or without disabling irqs for such a long period of time (which
> I 
> > think is not a nice thing to do either) OR is it acceptable
> (although 
> > not nice) to simply fix it this way, by disabling irqs while it
> loads 
> > the firmware?
> 
> I wonder if you're chasing ghosts; 4K stack kernels have a seperate
> stack for interrupts so... those should be safe.
> 
> Btw, you forgot to post a pointer to the source code of your driver,
> so
> it's a lot harder for us (read: impossible) to give you good advice..

As someone mentioned in another post, I believe what is causing this problem is a combination of factors.  The triggering of the softlockup detector seems to be what pushes it over the edge.  I think I will try as suggested to change the timer for it so that it does not trigger while the card is initializing.

If you'd like to see the source, here's a link:
http://svn.digium.com/view/zaptel/trunk/wct4xxp/

I can't give you the stack trace right now, since I'm not in the office, but it begins in the vpm450_init function and goes into the Octasic API functions, in the ChannelOpen routines as well as the chip initialization routines (the ones that load the firmware.

---
Matthew Fredrickson
Kernel Developer
Digium, Inc.