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Date:   Sat, 7 May 2022 14:05:08 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Muchun Song <songmuchun@bytedance.com>
Cc:     Mike Kravetz <mike.kravetz@oracle.com>, corbet@lwn.net,
        mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com,
        osalvador@suse.de, david@redhat.com, masahiroy@kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, duanxiongchun@bytedance.com, smuchun@gmail.com
Subject: Re: [PATCH v9 2/4] mm: memory_hotplug: override memmap_on_memory
 when hugetlb_free_vmemmap=on
Message-Id: <20220507140508.38c9e211eae4715134f9fa31@linux-foundation.org>
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On Wed, 4 May 2022 11:37:43 +0800 Muchun Song <songmuchun@bytedance.com> wrote:

> > Freeing HugeTLB vmemmap pages is not compatible with allocating memmap on
> > hot added memory. If "hugetlb_free_vmemmap=on" and
> > memory_hotplug.memmap_on_memory" are both passed on the kernel command line,
> > freeing hugetlb pages takes precedence.  However, the global variable
> > memmap_on_memory will still be set to 1, even though we will not try to
> > allocate memmap on hot added memory.
> > 
> > Not sure if that is more clear or not.
> > 
> 
> Clearer than mine.

I updated, thanks.