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

From: Jerome Glisse
Date: Fri Feb 22 2019 - 10:36:27 EST


On Fri, Feb 22, 2019 at 05:09:19PM +0800, Peter Xu wrote:
> 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").

No i was confuse when reading this patch i had the feeling it was
after the ioctl ignore my comment.

>
> >
> > Otherwise the patch itself is:
> >
> > Reviewed-by: Jérôme Glisse <jglisse@xxxxxxxxxx>
>
> Unless I found anything I've missed above... I'll temporarily pick
> this R-b for now then.

It is fine, the patch ordering was my confusion.

Cheers,
Jérôme