Re: [PATCH v2 15/26] userfaultfd: wp: drop _PAGE_UFFD_WP properly when fork

From: Peter Xu
Date: Fri Feb 22 2019 - 04:09:34 EST


On Thu, Feb 21, 2019 at 01:06:31PM -0500, Jerome Glisse wrote:
> On Tue, Feb 12, 2019 at 10:56:21AM +0800, Peter Xu wrote:
> > UFFD_EVENT_FORK support for uffd-wp should be already there, except
> > that we should clean the uffd-wp bit if uffd fork event is not
> > enabled. Detect that to avoid _PAGE_UFFD_WP being set even if the VMA
> > is not being tracked by VM_UFFD_WP. Do this for both small PTEs and
> > huge PMDs.
> >
> > Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
>
> This patch must be earlier in the serie, before the patch that introduce
> the userfaultfd API so that bisect can not end up on version where this
> can happen.

Yes it should be now? Since the API will be introduced until patch
21/26 ("userfaultfd: wp: add the writeprotect API to userfaultfd
ioctl").

>
> Otherwise the patch itself is:
>
> Reviewed-by: JÃrÃme Glisse <jglisse@xxxxxxxxxx>

Unless I found anything I've missed above... I'll temporarily pick
this R-b for now then.

Thanks,

--
Peter Xu