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From:   "Wang, Haiyue" <haiyue.wang@intel.com>
To:     "Huang, Ying" <ying.huang@intel.com>
CC:     "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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        "naoya.horiguchi@linux.dev" <naoya.horiguchi@linux.dev>,
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Subject: RE: [PATCH v3 1/2] mm: migration: fix the FOLL_GET failure on
 following huge page
Thread-Topic: [PATCH v3 1/2] mm: migration: fix the FOLL_GET failure on
 following huge page
Thread-Index: AQHYsELdwe4rYEhX3kmQ25LUIwgSE62vNNY6gAAAhrCAAAO+gA==
Date:   Mon, 15 Aug 2022 02:15:41 +0000
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> -----Original Message-----
> From: Wang, Haiyue
> Sent: Monday, August 15, 2022 10:11
> To: Huang, Ying <ying.huang@intel.com>
> Cc: linux-mm@kvack.org; linux-kernel@vger.kernel.org; akpm@linux-foundati=
on.org; david@redhat.com;
> linmiaohe@huawei.com; songmuchun@bytedance.com; naoya.horiguchi@linux.dev=
; alex.sierra@amd.com
> Subject: RE: [PATCH v3 1/2] mm: migration: fix the FOLL_GET failure on fo=
llowing huge page
>=20
> > -----Original Message-----
> > From: Huang, Ying <ying.huang@intel.com>
> > Sent: Monday, August 15, 2022 09:59
> > To: Wang, Haiyue <haiyue.wang@intel.com>
> > Cc: linux-mm@kvack.org; linux-kernel@vger.kernel.org; akpm@linux-founda=
tion.org; david@redhat.com;
> > linmiaohe@huawei.com; songmuchun@bytedance.com; naoya.horiguchi@linux.d=
ev; alex.sierra@amd.com
> > Subject: Re: [PATCH v3 1/2] mm: migration: fix the FOLL_GET failure on =
following huge page
> >
> > Haiyue Wang <haiyue.wang@intel.com> writes:
> >


> >
> > > This is an temporary solution to mitigate the racing fix.
> >
> > Why is it "racing fix"?  This isn't a race condition fix.
>=20
> The 'Fixes' commit is about race condition fix.
>=20
> How about " his is an temporary solution to mitigate the side effect
> Of the race condition fix"

Try to add more words to make things clean:

"This is an temporary solution to mitigate the side effect of the race
condition fix by calling follow_page() with FOLL_GET set."

>=20
> >
> > Best Regards,
> > Huang, Ying
> >
> > > After supporting follow huge page by FOLL_GET is done, this fix can b=
e
> > > reverted safely.
> > >
> > > Fixes: 4cd614841c06 ("mm: migration: fix possible do_pages_stat_array=
 racing with memory offline")
> > > Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
> >
> > [snip]