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Date:   Tue, 7 Jul 2020 12:56:41 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Barry Song <song.bao.hua@hisilicon.com>
Cc:     <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        <linuxarm@huawei.com>, Mike Kravetz <mike.kravetz@oracle.com>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        Roman Gushchin <guro@fb.com>
Subject: Re: [PATCH v3] mm/hugetlb: avoid hardcoding while checking if cma
 is enable
Message-Id: <20200707125641.dbd2ccd63f525aa5870069d8@linux-foundation.org>
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On Tue, 7 Jul 2020 16:02:04 +1200 Barry Song <song.bao.hua@hisilicon.com> wrote:

> hugetlb_cma[0] can be NULL due to various reasons, for example, node0 has
> no memory. so NULL hugetlb_cma[0] doesn't necessarily mean cma is not
> enabled. gigantic pages might have been reserved on other nodes.

I'm trying to figure out whether this should be backported into 5.7.1,
but the changelog doesn't describe any known user-visible effects of
the bug.  Are there any?