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Date:   Sat, 13 Aug 2022 16:28:37 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Haiyue Wang <haiyue.wang@intel.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org, david@redhat.com,
        linmiaohe@huawei.com, ying.huang@intel.com,
        songmuchun@bytedance.com, naoya.horiguchi@linux.dev
Subject: Re: [PATCH v1] mm: migration: fix the FOLL_GET failure on following
 huge page
Message-Id: <20220813162837.cc20e208e7a9d65fd2e7dc14@linux-foundation.org>
In-Reply-To: <20220812084921.409142-1-haiyue.wang@intel.com>
References: <20220812084921.409142-1-haiyue.wang@intel.com>
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On Fri, 12 Aug 2022 16:49:21 +0800 Haiyue Wang <haiyue.wang@intel.com> wrote:

> Not all huge page APIs support FOLL_GET option, so the __NR_move_pages
> will fail to get the page node information for huge page.

Which ones need fixing?

What are the user-visible runtime effects of this bug?

Is a -stable backport warranted?

> This is an temporary solution to mitigate the racing fix.
> 
> After supporting follow huge page by FOLL_GET is done, this fix can be
> reverted safely.
>