On Tue, Jul 14, 2020 at 12:11 PM Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Tue, Jul 14, 2020 at 9:08 AM Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> wrote: > > > > I was thinking we should not call move_page_tables() with overlapping ranges > > at all, just to keep things simple. > > No, we're not breaking the existing stack movement code just to keep > things simple. > > The rule is "make it as simple as possible, but no simpler". > > And "as possible" in the case of Linux means "no breaking of old > interfaces". The stack randomization movement most certainly counts. Hi Linus, I think you misunderstood me. I was not advocating breaking the stack movement code or breaking stack randomization, I was going to try to see if I could keep that working while not having to do an overlapping move. That would be what I would do in the future patch (until which as you mentioned, you would switch the WARN_ON to WARN_ON_ONCE). I agree with you that we keep things as simple as possible while not breaking functionality. Cheers, - Joel