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Date:   Fri, 29 Apr 2022 09:31:03 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Hongchen Zhang <zhanghongchen@loongson.cn>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Alistair Popple <apopple@nvidia.com>,
        Ralph Campbell <rcampbell@nvidia.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/swapops: make is_pmd_migration_entry more strict
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References: <1651131333-6386-1-git-send-email-zhanghongchen@loongson.cn>
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On Fri, Apr 29, 2022 at 10:23:08AM +0800, Hongchen Zhang wrote:
> Hello Peter,

Hi, Hongchen,

>   (1) the pmd passed to __split_huge_pmd_locked may be a none pmd,so it may
> be wrongly treated as a pmd migration entry.

With !ARCH_ENABLE_THP_MIGRATION is_pmd_migration_entry() returns 0
constantly.

>   (2) we are preparing to support thp migration on MIPS.

Makes sense (to not have Fixes then).  It'll be great if the objective of
the patch will be mentioned in the future.

Thanks for answering!

-- 
Peter Xu