Re: [PATCH v1 0/2] userfaultfd: clear the inherited uffd bit in move_swap_pte()

[Mike Rapoport]

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.