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Date:   Tue, 20 Jun 2023 17:21:10 -0400
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Subject: Re: [PATCH v4 1/7] mm/mremap: Optimize the start addresses in
 move_page_tables()
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From:   Joel Fernandes <joel@joelfernandes.org>
To:     Lorenzo Stoakes <lstoakes@gmail.com>
Cc:     linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kselftest@vger.kernel.org, linux-mm@kvack.org,
        Shuah Khan <shuah@kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Michal Hocko <mhocko@suse.com>,
        Kirill A Shutemov <kirill@shutemov.name>,
        "Liam R. Howlett" <liam.howlett@oracle.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Kalesh Singh <kaleshsingh@google.com>,
        Lokesh Gidra <lokeshgidra@google.com>,
        Vineeth Pillai <vineeth@bitbyteword.org>
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On 6/20/23 17:16, Joel Fernandes wrote:
> 
> Considering our discussion above that hugetlb mremap addresses should always 
> starts at a PMD boundary, maybe I can just add a warning to the if() like so to 
> detect any potential?
> 
>      if (is_vm_hugetlb_page(vma)) {
>          WARN_ON_ONCE(old_addr - old_end != len);

Oops, I meant WARN_ON_ONCE(old_end - old_addr != len);

to make sure we did not mess up hugetlb mremaps.

thanks,

  - Joel