Re: [PATCH] mm: Fix invalid page pointer returned with FOLL_PIN gups

From: Peter Xu
Date: Fri Jan 28 2022 - 01:16:15 EST


On Thu, Jan 27, 2022 at 09:57:34PM -0800, John Hubbard wrote:
> On 1/27/22 19:26, Peter Xu wrote:
> ...
> > I see that both you and John has a strong preference on at least the
> > WARN_ON_ONCE() in the patch.
> >
> > Do you think it's okay I repost with only the one-liner fix, which will keep
> > the Fixes but drop the WARN_ON_ONCE? Then we can leave the rest as follow up.
> >
>
> I think that's OK with me, anyway. You'll recall that I initially requested
> that you split this into two patches, after all.
>
> Would you like me to post a follow-up that does the refactoring that Jason
> and I are requesting? I see that we have some fundamental differences in
> opinion about how this should be done, so rather than drive you crazy with
> debating, maybe that would be smoother? :)

Sure thing. :-)

Please just double check that the pud devmap will still always work on mlock().
I believe both of you are much more familiar than me on that; it just still
seems a little bit tricky.

I'll repost this one, thanks.

--
Peter Xu