static variables, functions, ... only affect linking, meaning as symbols they are restricted in use to the file they are declared in, but at the point of use it's a pointer/memory location and as such can be passed around and used as much as you want, allowing you to call other functions with that variable. As an example take a look at static function jump tables or plugin setups. You use static declarations to prevent symbol clashes and restrict access but you pass out a pointer to that table during initialization so your functions/plugin can be used.

Alright, so can you post what code works and what code doesn't. Maybe there's something that has changed that we are missing.

Hi,

@Estabroo: thanks for your explanation.
@Metaschisma: the last code that I posted was returning a wrong output (hash value) but when I replaced, in the same code, the declaration of "static uint8_t m[5000]" by "m = vmalloc(5000 * sizeof(uint8_t))" (with a corresponding vfree(m)) inside the "init_module()", I got the good result (hash value).

Can you try using a for loop to initialize instead of memset ?