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Date:   Fri, 26 Aug 2022 20:19:41 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Charan Teja Kalla <quic_charante@quicinc.com>
Cc:     <mhocko@suse.com>, <david@redhat.com>, <vbabka@suse.cz>,
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        <quic_pkondeti@quicinc.com>, <minchan@google.com>,
        <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>
Subject: Re: [PATCH V5] mm: fix use-after free of page_ext after race with
 memory-offline
Message-Id: <20220826201941.de6ed957a0d6547b2d501c19@linux-foundation.org>
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References: <1661496993-11473-1-git-send-email-quic_charante@quicinc.com>
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On Fri, 26 Aug 2022 12:26:33 +0530 Charan Teja Kalla <quic_charante@quicinc.com> wrote:

> The below is one path where race between page_ext and  offline of the
> respective memory blocks will cause use-after-free on the access of
> page_ext structure.

What are people's thoughts on a -stable backport?  It looks like the
bug has been there for years and the means of hitting it are obscure
and the patch isn't minor, so I'm thinking no?