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Date:   Wed, 21 Jun 2023 15:46:57 -0700
From:   Mike Kravetz <mike.kravetz@oracle.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Sidhartha Kumar <sidhartha.kumar@oracle.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org,
        Matthew Wilcox <willy@infradead.org>,
        Ackerley Tng <ackerleytng@google.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Vishal Annapurve <vannapurve@google.com>,
        Erdem Aktas <erdemaktas@google.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 2/2] hugetlb: revert use of page_cache_next_miss()
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On 06/21/23 15:39, Andrew Morton wrote:
> On Wed, 21 Jun 2023 15:19:58 -0700 Sidhartha Kumar <sidhartha.kumar@oracle.com> wrote:
> 
> > > IMPORTANT NOTE FOR STABLE BACKPORTS:
> > > This patch will apply cleanly to v6.3.  However, due to the change of
> > > filemap_get_folio() return values, it will not function correctly.  This
> > > patch must be modified for stable backports.
> > 
> > This patch I sent previously can be used for the 6.3 backport:
> > 
> > https://lore.kernel.org/lkml/b5bd2b39-7e1e-148f-7462-9565773f6d41@oracle.com/T/#me37b56ca89368dc8dda2a33d39f681337788d13c
> 
> Are we suggesting that this be backported?  If so, I'll add the cc:stable.
> 
> Because -stable maintainers have been asked not to backport MM patches to
> which we didn't add the cc:stable.

Yes, we need to get a fix into 6.3 as well.

The 'issue' with a backport is noted in the IMPORTANT NOTE above.

My concern is that adding cc:stable will have it automatically picked up
and this would make things worse than they are in 6.3.

My 'plan' was to not add the cc:stable, but manually create a patch for
6.3 once this goes upstream.  Honestly, I am not sure what is the best
way to deal with this.  I could also try to catch the email about the
automatic backport and say 'no, use this new patch instead'.
-- 
Mike Kravetz