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From:   "Luck, Tony" <tony.luck@intel.com>
To:     Mike Kravetz <mike.kravetz@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>
CC:     Liu Shixin <liushixin2@huawei.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Muchun Song <muchun.song@linux.dev>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH -next] mm: hwpoison: support recovery from HugePage
 copy-on-write faults
Thread-Topic: [PATCH -next] mm: hwpoison: support recovery from HugePage
 copy-on-write faults
Thread-Index: AQHZbFDq19fMxv6l/0SbTe2cXT0UDa8n/G4AgAA+bwCAAAbNAIAACa8AgAALdoCAABLfsA==
Date:   Thu, 13 Apr 2023 00:47:37 +0000
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References: <20230411092741.780679-1-liushixin2@huawei.com>
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> I do not think cc:stable is necessary/desirable.  Why?
>
> a873dfe1032a was an enhancement to better handle copying pages with memor=
y
> errors in the kernel.  IIUC, we never handled that situation in the past.
> I would not call the fact that it did not take hugetlb into account a bug=
.
> Although, some might argue that it should have addressed all callers of
> copy_user_highpage which would have included hugetlb.  IMO, There would b=
e
> little to gain by backporing to 6.1 as the issue of copying pages with
> errors has existed forever.  Perhaps Tony will comment as I was not invol=
ved
> in a873dfe1032a.

I concur. We are gradually fixing more cases where Linux consumes
poison data in kernel context. But this is an incremental process to
improve overall reliability. Backporting to stable and long term releases
isn't a priority.

-Tony