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From: Wonhyuk Yang <vvghjk1234@gmail.com>
Date: Wed, 24 Nov 2021 08:59:20 +0900
Message-ID: <CAEcHRTo8wKgLLzjxgH+-fva87k7mhQFpzVQae9z5n+9orok38w@mail.gmail.com>
Subject: Re: [Question] The necessity of transaction ID in SLUB.
To: Christoph Lameter <cl@gentwo.org>
Cc: linux-mm@kvack.org, Joonsoo Kim <iamjoonsoo.kim@lge.com>
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List-ID: <linux-mm.kvack.org>

Now I know what I missed!

I missed that the freepointer may no more be valid because any other
preemptions. Also, It is possible that cpu_slab->freelist is unchanged
but it's freepointer may be changed. This is why we guarantee that
there is no update before, right?

Thanks to the answer, I was able to solve my question.