Several MM selftests report failures when the test environment lacks
an underlying prerequisite, such as fallocate() support, MADV_REMOVE,
local page-cache semantics, or swap.

This series converts those unsupported cases to SKIP while preserving
failures for unexpected errors. It also allows migration tests to retry
transient move_pages() failures.

Tested on an arm64 Ampere system using an NFS root filesystem. The MM
selftest run completed without failures or errors. Also verified on
x86_64 to ensure the changes do not cause unexpected errors.

Changes since v1:
- Print swapout diagnostics before reporting no-swap skips.
- Limit the NFS skip to the hard dirty-page variant.
- Retry per-page failures for the full runtime.
- Verify that both alternating NUMA targets are reached.

Muhammad Usama Anjum (5):
  selftests/mm: skip COW tmpfile cases when fallocate() is unsupported
  selftests/mm: skip guard hole-punch test if MADV_REMOVE is unsupported
  selftests/mm: skip khugepaged swap tests without swap
  selftests/mm: skip hard dirty page-cache test on NFS
  selftests/mm: retry migration failures for the full runtime

 tools/testing/selftests/mm/cow.c            |  9 +++--
 tools/testing/selftests/mm/guard-regions.c  | 10 ++++--
 tools/testing/selftests/mm/khugepaged.c     | 38 ++++++++++++++++++--
 tools/testing/selftests/mm/memory-failure.c |  9 +++--
 tools/testing/selftests/mm/migration.c      | 39 +++++++++++----------
 5 files changed, 78 insertions(+), 27 deletions(-)

-- 
2.47.3