Borlizzi Giacomo giacomo.borlizzi at
Wed Jan 17 04:31:17 EST 2001

I'm changing the operating system for my powerpc 860 board from
linux-2.2.13 to linux-2.4.0-test9.
With 2.2.13 version I have running the kernel and obtained the prompt of
sash .....
On 2.4 version it don't work instead.
My configuration foreseen  KERNELBASE set to 0x00000000 instead of
this configuration seems be not  compatible with MMU initialization
And infact during the execution of setup_arch() when the function
va_to_pte() is called
the  "mm = current->mm;" statment is executed (I report here some code)

pte_t *va_to_pte(unsigned long address)
 pgd_t *dir;
 pmd_t *pmd;
 pte_t *pte;
 struct mm_struct *mm;

 if (address < TASK_SIZE)           /* TASK_SIZE is 0x80000000 */
  mm = current->mm;                      <---this statment is executed
  mm = &init_mm;

 dir = pgd_offset(mm, address & PAGE_MASK);

but at this moment "current" is not initialized????
on the 2.2.13 instead the function was have two parameters...

That is a big change... where I can found information on use of MMU on
and on means of those  data structures?

Thanks you in advanced and sorry for my bad English
/Giacomo Borlizzi

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