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Subject: Re: [PATCH] mm: Make copy_huge_page() always available
To:     "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Mina Almasry <almasrymina@google.com>
Cc:     YueHaibing <yuehaibing@huawei.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Peter Xu <peterx@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20210712153207.39302-1-willy@infradead.org>
From:   Mike Kravetz <mike.kravetz@oracle.com>
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On 7/12/21 8:32 AM, Matthew Wilcox (Oracle) wrote:
> Rewrite copy_huge_page() and move it into mm/util.c so it's always
> available.  Fixes an exposure of uninitialised memory on configurations
> with HUGETLB and UFFD enabled and MIGRATION disabled.
> 
> Fixes: 8cc5fcbb5be8 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
>  include/linux/migrate.h |  5 -----
>  include/linux/mm.h      |  1 +
>  mm/migrate.c            | 48 -----------------------------------------
>  mm/util.c               | 10 +++++++++
>  4 files changed, 11 insertions(+), 53 deletions(-)

Thanks Matthew,

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
-- 
Mike Kravetz