Re: [PATCH 00/11] Use global pages with PTI

Linus Torvalds
2018-03-24T00:54:38Z

On Fri, Mar 23, 2018 at 5:46 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> It is, of course, possible that I misunderstood what you actually
> benchmarked. But I assume the above benchmark numbers are with the
> whole "don't even do global entries if you have PCID".

Oh, I went back and read your description, and realized that I _had_
misunderstood what you did.

I thought you didn't bother with global pages at all when you had PCID.

But that's not what you meant. You always do global for the actual
user-mapped kernel pages, but when you don't have PCID you do *all*
kernel test as global, whether shared or not.

So I entirely misread what the latest change was.

Linus