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From:   "Luck, Tony" <tony.luck@intel.com>
To:     "Williams, Dan J" <dan.j.williams@intel.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        Andrew Morton <akpm@linux-foundation.org>
CC:     Miaohe Lin <linmiaohe@huawei.com>,
        Matthew Wilcox <willy@infradead.org>,
        Shuai Xue <xueshuai@linux.alibaba.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Nicholas Piggin <npiggin@gmail.com>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
Subject: RE: [PATCH v2] mm, hwpoison: Try to recover from copy-on write faults
Thread-Topic: [PATCH v2] mm, hwpoison: Try to recover from copy-on write
 faults
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Date:   Wed, 19 Oct 2022 20:30:41 +0000
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> Given there is no use case for the residue value returned by
> copy_mc_to_kernel() perhaps just return EHWPOISON directly from
> copyuser_highpage_mc() in the short-copy case?

I don't think it hurts to keep the return value as residue count. It isn't
making that code any more complex and could be useful someday.

Other feedback looks good and I have applied ready for next version.

Thanks for the review.

-Tony