Re: [PATCH 1/3] mm/hugetlb: Fix race condition of uffd missing/minor handling

[Peter Xu]

On Mon, Oct 03, 2022 at 02:45:47PM -0700, Mike Kravetz wrote:
> This also explains why the new locking exposes the race.
> hugetlb_change_protection needs to take the i_mmap_sema in write mode because
> it could unshare pmds.  Previously, hugetlb page faults took i_mmap_sema in
> read mode so this race could not happen.

Makes sense, thanks for explaining.

-- 
Peter Xu