hash_mm_context
struct hash_mm_context *hash_context;
static struct hash_mm_context init_hash_mm_context;
memset(mm->context.hash_context, 0, sizeof(struct hash_mm_context));
memcpy(mm->context.hash_context, current->mm->context.hash_context, sizeof(struct hash_mm_context));
mm->context.hash_context = kmalloc_obj(struct hash_mm_context);