Stack overflow problem in kernel module

[Karthik Subramanian <karthik301176@xxxxxxxxx>]

Hi Folks,

I'm about to ask a potentially stupid question, so I request you to be
patient with me, and if I'm missing something and need to read up on
it, please do point me to appropriate material :-).

I'm writing a test suite for a kernel module, and am facing this problem: 

I have a function say foobar(). 

The moment I declare a big array inside the function, like below, it
causes the kernel to crash
anytime I call the function.

int foobar (int args)
{

  /* local var declarations */

  char somebuffer[1024];  

  /* rest of the function */

}

I was told that it's bad design to use local variables that are as
huge as this in kernel modules - so my questions are:

1. Why is it a bad idea to use huge local arrays in kernel modules?
2. When the kernel crashed, what followed on screen mentioned a stack
overflow. How can I find out how much stack area I have, and whether
or not a particular function can potentially cause stack overflow?

Thanks for your patience and your help :-)

Regards,
Karthik.


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