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From:   Alexander Potapenko <glider@google.com>
Date:   Wed, 12 Jul 2023 11:30:11 +0200
Message-ID: <CAG_fn=Vj+rqkz0_3kvBoBVoxET10KV-zoD=YtJmCfsA8YEMemg@mail.gmail.com>
Subject: Re: [PATCH v2] mm: kfence: allocate kfence_metadata at runtime
To:     Peng Zhang <zhangpeng.00@bytedance.com>
Cc:     elver@google.com, dvyukov@google.com, akpm@linux-foundation.org,
        kasan-dev@googlegroups.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, muchun.song@linux.dev
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> Below is the numbers obtained in qemu (with default 256 objects).
> before: Memory: 8134692K/8388080K available (3668K bss)
> after: Memory: 8136740K/8388080K available (1620K bss)
> More than expected, it saves 2MB memory. It can be seen that the size
> of the .bss section has changed, possibly because it affects the linker.

The size of .bss should only change by ~288K. Perhaps it has crossed
the alignment boundary for .bss, but this effect cannot be guaranteed
and does not depend exclusively on this patch.
I suggest that you omit these lines from the patch description, as
they may confuse the readers.