Date:   Thu, 2 Mar 2023 17:50:03 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Peter Xu <peterx@redhat.com>
Cc:     James Houghton <jthoughton@google.com>,
        David Hildenbrand <david@redhat.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Anish Moorthy <amoorthy@google.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: teach mincore_hugetlb about pte markers
Message-Id: <20230302175003.7772edcfc28cf0bd67f45e72@linux-foundation.org>
In-Reply-To: <ZAEkEDcoIZRrAIwX@x1n>
References: <20230302222404.175303-1-jthoughton@google.com>
        <ZAEkEDcoIZRrAIwX@x1n>
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On Thu, 2 Mar 2023 17:32:48 -0500 Peter Xu <peterx@redhat.com> wrote:

> On Thu, Mar 02, 2023 at 10:24:04PM +0000, James Houghton wrote:
> > By checking huge_pte_none(), we incorrectly classify PTE markers as
> > "present". Instead, check huge_pte_none_mostly(), classifying PTE
> > markers the same as if the PTE were completely blank.
> > 
> > PTE markers, unlike other kinds of swap entries, don't reference any
> > physical page and don't indicate that a physical page was mapped
> > previously. As such, treat them as non-present for the sake of
> > mincore().
> > 
> > Fixes: 5c041f5d1f23 ("mm: teach core mm about pte markers")
> > Signed-off-by: James Houghton <jthoughton@google.com>
> 
> Acked-by: Peter Xu <peterx@redhat.com>
> 

I think I'll add cc:stable to this.