Re: [PATCH v2 10/39] x86/mm: Introduce _PAGE_COW

From: Peter Zijlstra
Date: Wed Oct 05 2022 - 07:34:57 EST

On Thu, Sep 29, 2022 at 03:29:07PM -0700, Rick Edgecombe wrote:

Mucho confusion here:

> (a) (Write=0,Cow=1,Dirty=0) A modified, copy-on-write (COW) page.
> (b) (Write=0,Cow=1,Dirty=0) A R/O page that has been COW'ed. The user page
> (d) (Write=0,Cow=1,Dirty=0) A shared shadow stack PTE. When a shadow stack

are all identical cases;

> (c) (Write=0,Cow=0,Dirty=1) A shadow stack PTE.
> (e) (Write=0,Cow=0,Dirty=1) A Cow PTE created when a processor without

as are these.