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Message-ID: <19b49f1f-9d2d-6cf1-e764-ca4219b22ab9@redhat.com>
Date:   Fri, 16 Dec 2022 17:37:23 +0100
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Subject: Re: [PATCH 1/2] mm/uffd: Fix pte marker when fork() without fork
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To:     Peter Xu <peterx@redhat.com>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Andrea Arcangeli <aarcange@redhat.com>,
        Pengfei Xu <pengfei.xu@intel.com>,
        Nadav Amit <nadav.amit@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Huang Ying <ying.huang@intel.com>, stable@vger.kernel.org
References: <20221214200453.1772655-1-peterx@redhat.com>
 <20221214200453.1772655-2-peterx@redhat.com>
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 <8c36dd0a-90be-91bf-0ded-55b34ee0a770@redhat.com> <Y5ybyFa5U9VzVcwg@x1n>
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From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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On 16.12.22 17:24, Peter Xu wrote:
> On Fri, Dec 16, 2022 at 04:57:33PM +0100, David Hildenbrand wrote:
>> I'm more concerned about backports, when one backports #1 but not #2. In
>> theory, patch #2 fixes patch #1, because that introduced IMHO a real
>> regression -- a possible memory corruption when discarding a hwpoison
>> marker. Warnings are not nice but at least indicate that something needs a
>> second look.
> 
> Note that backporting patch 1 only is exactly what I wanted to do here - it
> means his/her tree should not have the swapin error pte markers at all.
> 
> The swapin error pte marker change only existed for a few days in Linus's
> tree, so no one should be backporting patch 2.

Right, and these patches are supposed to land in 6.2 as well. Makes 
sense to me then.

Especially, the other parts in patch #2 are worth being in a separate patch.

Acked-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb