Re: [PATCH v3 5/5] mm: userfaultfd: add UFFDIO_CONTINUE_MODE_WP to install WP PTEs

Peter Xu
2023-03-07T01:23:45Z

On Mon, Mar 06, 2023 at 02:50:24PM -0800, Axel Rasmussen wrote:
> UFFDIO_COPY already has UFFDIO_COPY_MODE_WP, so when installing a new
> PTE to resolve a missing fault, one can install a write-protected one.
> This is useful when using UFFDIO_REGISTER_MODE_{MISSING,WP} in
> combination.
>
> So, add an analogous UFFDIO_CONTINUE_MODE_WP, which does the same thing
> but for *minor* faults.
>
> Update the selftest to do some very basic exercising of the new flag.
>
> Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>

Some mentioning on the use case would be nice. :) No objection having it.

Acked-by: Peter Xu <peterx@redhat.com>

Thanks,

--
Peter Xu