@@ -40,29 +40,8 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
goto out_free;
}
- /*
- * Ensure the new MM is clean and nothing unwanted is mapped.
- *
- * TODO: We should clear the memory up to STUB_START to ensure there is
- * nothing mapped there, i.e. we (currently) have:
- *
- * |- user memory -|- unused -|- stub -|- unused -|
- * ^ TASK_SIZE ^ STUB_START
- *
- * Meaning we have two unused areas where we may still have valid
- * mappings from our internal clone(). That isn't really a problem as
- * userspace is not going to access them, but it is definitely not
- * correct.
- *
- * However, we are "lucky" and if rseq is configured, then on 32 bit
- * it will fall into the first empty range while on 64 bit it is going
- * to use an anonymous mapping in the second range. As such, things
- * continue to work for now as long as we don't start unmapping these
- * areas.
- *
- * Change this to STUB_START once we have a clean userspace.
- */
- unmap(new_id, 0, TASK_SIZE);
+ /* Ensure the new MM is clean and nothing unwanted is mapped */
+ unmap(new_id, 0, STUB_START);
return 0;