Re: [PATCH v23 07/28] x86/mm: Remove _PAGE_DIRTY from kernel RO pages

2021-03-22 Thread Yu, Yu-cheng
On 3/22/2021 2:13 AM, Kirill A. Shutemov wrote: 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

Re: [PATCH v23 07/28] x86/mm: Remove _PAGE_DIRTY from kernel RO pages

2021-03-22 Thread Kirill A. Shutemov
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 Shado

[PATCH v23 07/28] x86/mm: Remove _PAGE_DIRTY from kernel RO pages

2021-03-16 Thread Yu-cheng Yu
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 re