v3: - Rebase to akpm mm-unstable v2: - Fix the commit message of patch 1, replacing CoW with wr-unprotect example Currently akpm mm-unstable fails with uffd hugetlb private mapping test randomly on a write check. The initial bisection of that points to the recent pmd unshare series, but it turns out there's no direction relationship with the series but only some timing change caused the race to start trigger. The race should be fixed in patch 1. Patch 2 is a trivial cleanup on the similar race with hugetlb migrations, patch 3 comment on the write check so when anyone read it again it'll be clear why it's there. Thanks, Peter Xu (3): mm/hugetlb: Fix race condition of uffd missing/minor handling mm/hugetlb: Use hugetlb_pte_stable in migration race check mm/selftest: uffd: Explain the write missing fault check mm/hugetlb.c | 66 ++++++++++++++++++++---- tools/testing/selftests/vm/userfaultfd.c | 22 +++++++- 2 files changed, 76 insertions(+), 12 deletions(-) -- 2.37.3