Hi, On Sat, Sep 19, 2026 at 09:46:28AM +0900, Donggeun Yoo wrote: > UFFDIO_MOVE on a swapped-out page installs the source PTE at the > destination unchanged, so a uffd bit set on the source lands in a > destination VMA that was never registered for write protection, and > nothing clears it afterwards. Patch 1 clears the bit unless the > destination is RWP-registered, which is what the present-page and > zeropage move paths already do. Patch 2 adds the test that catches it.
This and changelogs read like an LLM generated text. Please add attribution as per https://docs.kernel.org/process/coding-assistants.html#attribution > x86_64 defconfig plus USERFAULTFD, TRANSPARENT_HUGEPAGE, GUP_TEST and a > swap device, under QEMU, base 17e7b8eacf4c: > > uffd-unit-tests before after > move-swap-wp on anon not ok ok > the other 114 unit tests ok ok > uffd-wp-mremap, 38 tests ok ok > > pagemap bit 57 at the destination before after > swapped page, dst not armed set clear > swapped page, dst WP-armed set clear > swapped page, dst RWP-armed set set > resident page, dst WP-armed clear clear > > MADV_COLLAPSE over 2 MB at dst EINVAL 0 > > Donggeun Yoo (2): > userfaultfd: clear the inherited uffd bit in move_swap_pte() > selftests/mm: add a test for UFFDIO_MOVE of a write-protected swap > entry > > mm/userfaultfd.c | 2 + > tools/testing/selftests/mm/uffd-unit-tests.c | 61 ++++++++++++++++++++ > 2 files changed, 63 insertions(+) > > > base-commit: 17e7b8eacf4cac800a4fc89a28729df72a2dabda > -- > 2.53.0 > -- Sincerely yours, Mike.
