# Re: \[PATCH v23 07/28\] x86/mm: Remove \_PAGE\_DIRTY from kernel RO pages

- From: Kirill A. Shutemov \<hidden\>
- Date: 2021-03-22 09:14:38 
- List: linux-arch
- Page: https://ratatoskr.run/linux-arch/2021/03/6309798
- Thread: https://ratatoskr.run/linux-doc/2021/03/6303369/t.md

```text
On Tue, Mar 16, 2021 at 08:10:33AM -0700, Yu-cheng Yu wrote:
> The x86 family of processors do not directly create read-only and Dirty
> PTEs.  These PTEs are created by software.  One such case is that kernel
> read-only pages are historically setup as Dirty.
> 
> New processors that support Shadow Stack regard read-only and Dirty PTEs as
> shadow stack pages.  This results in ambiguity between shadow stack and
> kernel read-only pages.  To resolve this, removed Dirty from kernel read-
> only pages.
> 
> Signed-off-by: Yu-cheng Yu <redacted>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Kees Cook <redacted>
> Cc: Thomas Gleixner <redacted>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Peter Zijlstra <peterz@infradead.org>

Looks good to me.

Reviewed-by: Kirill A. Shutemov <redacted>

-- 
 Kirill A. Shutemov
```