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Date:   Thu, 11 Aug 2022 15:01:05 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Peter Xu <peterx@redhat.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        David Hildenbrand <david@redhat.com>,
        Mike Rapoport <rppt@linux.vnet.ibm.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Nadav Amit <nadav.amit@gmail.com>,
        Axel Rasmussen <axelrasmussen@google.com>
Subject: Re: [PATCH] mm/uffd: Reset write protection when unregister with
 wp-mode
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On Thu, 11 Aug 2022 17:23:14 -0400 Peter Xu <peterx@redhat.com> wrote:

> On Thu, Aug 11, 2022 at 02:11:44PM -0700, Andrew Morton wrote:
> > On Thu, 11 Aug 2022 16:13:40 -0400 Peter Xu <peterx@redhat.com> wrote:
> > 
> > > I added a Fixes upon introducing of uffd-wp shmem+hugetlbfs because that's
> > > the only issue reported so far and that's the commit David's reproducer
> > > will start working (v5.19+).  But the whole idea actually applies to not
> > > only file memories but also anonymous.  It's just that we don't need to fix
> > > anonymous prior to v5.19- because there's no known way to exploit.
> > 
> > I added a cc:stable to this.
> 
> Thanks, Andrew.  I'll remember to do so in future patches when Fixes apply.
> 

Only if we want the fix to be backported!

I mean, it's legitimate and sensible to add a Fixes: to a patch which
fixes a comment typo, but we don't want that backported.

And sometimes a fix is too complex and the problem too small to warrant
a backport, but we still want that Fixes: tag.