On Tue, Apr 11, 2023 at 08:16:46PM -0700, Stefan Roesch wrote:
> case PR_SET_VMA:
> error = prctl_set_vma(arg2, arg3, arg4, arg5);
> break;
> +#ifdef CONFIG_KSM
> + case PR_SET_MEMORY_MERGE:
> + if (mmap_write_lock_killable(me->mm))
> + return -EINTR;
> +
> + if (arg2) {
> + int err = ksm_add_mm(me->mm);
> +
> + if (!err)
> + ksm_add_vmas(me->mm);
in the last version of this patch, you reported the error. Now you
swallow the error. I have no idea which is correct, but you've
changed the behaviour without explaining it, so I assume it's wrong.
> + } else {
> + clear_bit(MMF_VM_MERGE_ANY, &me->mm->flags);
> + }
> + mmap_write_unlock(me->mm);
> + break;
> + case PR_GET_MEMORY_MERGE:
> + if (arg2 || arg3 || arg4 || arg5)
> + return -EINVAL;
> +
> + error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags);
> + break;
Why do we need a GET? Just for symmetry, or is there an actual need for
it?
