Re: [PATCH v2 22/26] userfaultfd: wp: enabled write protection in userfaultfd API

Jerome Glisse
2019-02-21T18:29:40Z

On Tue, Feb 12, 2019 at 10:56:28AM +0800, Peter Xu wrote:
> From: Shaohua Li <shli@fb.com>
>
> Now it's safe to enable write protection in userfaultfd API
>
> Cc: Andrea Arcangeli <aarcange@redhat.com>
> Cc: Pavel Emelyanov <xemul@parallels.com>
> Cc: Rik van Riel <riel@redhat.com>
> Cc: Kirill A. Shutemov <kirill@shutemov.name>
> Cc: Mel Gorman <mgorman@suse.de>
> Cc: Hugh Dickins <hughd@google.com>
> Cc: Johannes Weiner <hannes@cmpxchg.org>
> Signed-off-by: Shaohua Li <shli@fb.com>
> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>

Maybe fold that patch with the previous one ? In any case:

Reviewed-by: Jérôme Glisse <jglisse@redhat.com>

> ---
> include/uapi/linux/userfaultfd.h | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h
> index 1b977a7a4435..a50f1ed24d23 100644
> --- a/include/uapi/linux/userfaultfd.h
> +++ b/include/uapi/linux/userfaultfd.h
> @@ -19,7 +19,8 @@
> * means the userland is reading).
> */
> #define UFFD_API ((__u64)0xAA)
> -#define UFFD_API_FEATURES (UFFD_FEATURE_EVENT_FORK | \
> +#define UFFD_API_FEATURES (UFFD_FEATURE_PAGEFAULT_FLAG_WP | \
> + UFFD_FEATURE_EVENT_FORK | \
> UFFD_FEATURE_EVENT_REMAP | \
> UFFD_FEATURE_EVENT_REMOVE | \
> UFFD_FEATURE_EVENT_UNMAP | \
> @@ -34,7 +35,8 @@
> #define UFFD_API_RANGE_IOCTLS \
> ((__u64)1 << _UFFDIO_WAKE | \
> (__u64)1 << _UFFDIO_COPY | \
> - (__u64)1 << _UFFDIO_ZEROPAGE)
> + (__u64)1 << _UFFDIO_ZEROPAGE | \
> + (__u64)1 << _UFFDIO_WRITEPROTECT)
> #define UFFD_API_RANGE_IOCTLS_BASIC \
> ((__u64)1 << _UFFDIO_WAKE | \
> (__u64)1 << _UFFDIO_COPY)
> --
> 2.17.1
>