Re: How to detect STACKOVEFLOW on mips

[Ralf Baechle <ralf@linux-mips.org>]

On Mon, Jul 05, 2010 at 02:09:31PM +0100, Matt Fleming wrote:

> > Which often isn't so helpful.  The alarm gets triggered on the last stack
> > pointer decrement but according to murphy the overflow has happened 10
> > levels up in the callchain.
> 
> Last decrement? The alarm should be triggered the next time the
> function in which the overflow occurs makes a function call. I don't
> see how you could go down a level of the callchain and not trigger the
> alarm if the overflow has happened?

guilt()
{
        char array[6000];

        blurb(&array);
}

blurb(void *p)
{
        frob(p);
}

With the deep nesting of the current kernel there is a good chance a
check in mcount will not be triggered in blurb() but possibly in frob
or even further down the callchain.

  Ralf