protect_memory(stack, (1 << CONFIG_KERNEL_STACK_ORDER) * PAGE_SIZE, 1, 1, 0, 1); 
os_protect_memory((void *) stack, (1 << CONFIG_KERNEL_STACK_ORDER) * PAGE_SIZE, 1, 1, 0); 
void unprotect_stack(unsigned long stack){	protect_memory(stack, (1 << CONFIG_KERNEL_STACK_ORDER) * PAGE_SIZE, 		       1, 1, 0, 1);}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/0f80bc85c587e8fdeecece4f294a47eca4922ea2/init_task.c/clean/arch/um/kernel/init_task.c