On Sat, May 20, 2023 at 12:14 AM Joel Fernandes joel@joelfernandes.org wrote:
On Sat, May 20, 2023 at 12:01 AM Linus Torvalds torvalds@linux-foundation.org wrote:
On Fri, May 19, 2023 at 8:57 PM Joel Fernandes joel@joelfernandes.org wrote:
I also realize that I don't really need to check whether the masked source address falls under a VMA neighboring to that of the source's.
I don't think that's true.
You can't start randomly moving other source vma's that may have other contents.
If the beginning part of the PMD is not mapped at the destination, I thought maybe a whole PMD could be moved to it. But I guess not because we don't want those contents to be accessible. So then in that case we have to forbid the optimization for all intra-VMA moves except those involving the stack. I will think more about it.
Duh, we can't move crap from the source like that also because it has real data. I think I got confused between "moving" and "copying". I feel silly, maybe it is time to go to sleep and live to fight another day.
- Joel