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Date:   Tue, 9 Aug 2022 18:57:14 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Charan Teja Kalla <quic_charante@quicinc.com>
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        <sieberf@amazon.com>, <shakeelb@google.com>, <sjpark@amazon.de>,
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        <quic_pkondeti@quicinc.com>, <linux-kernel@vger.kernel.org>,
        <linux-mm@kvack.org>
Subject: Re: [PATCH V3] mm: fix use-after free of page_ext after race with
 memory-offline
Message-Id: <20220809185714.5af7057c1270b11079cb196a@linux-foundation.org>
In-Reply-To: <1660056403-20894-1-git-send-email-quic_charante@quicinc.com>
References: <1660056403-20894-1-git-send-email-quic_charante@quicinc.com>
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On Tue, 9 Aug 2022 20:16:43 +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.

Has this race ever been observed at runtime?

Given the size of the fix, I'm looking for excuses to not backport it
into -stable kernels!