Re: [PATCH v25 20/30] mm/mprotect: Exclude shadow stack from preserve_write

On Thu, Apr 15, 2021 at 03:14:09PM -0700, Yu-cheng Yu wrote:

In change_pte_range(), when a PTE is changed for prot_numa, _PAGE_RW is
preserved to avoid the additional write fault after the NUMA hinting fault.
However, pte_write() now includes both normal writable and shadow stack
(RW=0, Dirty=1) PTEs, but the latter does not have _PAGE_RW and has no need
to preserve it.

Exclude shadow stack from preserve_write test, and apply the same change to
change_huge_pmd().

Signed-off-by: Yu-cheng Yu <redacted>

Reviewed-by: Kirill A. Shutemov <redacted>

-- 
 Kirill A. Shutemov