[PATCH v5 0/2] fs/proc/task_mmu: fix PAGEMAP_SCAN written state for PMD holes

[Kiryl Shutsemau]

From: "Kiryl Shutsemau (Meta)" <kas@xxxxxxxxxx>

Patch 1 fixes PAGEMAP_SCAN reporting a PMD hole in a uffd-wp VMA as
not-written (Cc stable). Patch 2 adds the selftest, split out so it is
not backported.

Changes since v4 [1], addressing David's review:
  - Split the selftest into a separate patch (2/2); only the fix (1/2)
    is Cc stable.
  - Rework the commit message and shorten the code comment.
  - Rework the test: mirror unpopulated_scan_test(), skip-and-continue
    on setup failure, rename to unpopulated_thp_scan_test().

[1] https://lore.kernel.org/all/20260713091710.206548-1-kirill@xxxxxxxxxxxxx/

Kiryl Shutsemau (Meta) (2):
  fs/proc/task_mmu: fix PAGEMAP_SCAN written state for PMD holes
  selftests/mm: add PAGEMAP_SCAN test for THP PMD holes

 fs/proc/task_mmu.c                         | 20 ++++++-
 tools/testing/selftests/mm/pagemap_ioctl.c | 66 +++++++++++++++++++++-
 2 files changed, 83 insertions(+), 3 deletions(-)


base-commit: 9795ad96d277c4af049fe30de1cebd4e39d7bcbe
-- 
2.54.0