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Date:   Mon, 7 Jun 2021 10:31:21 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     Kefeng Wang <wangkefeng.wang@huawei.com>,
        Mike Rapoport <rppt@kernel.org>,
        uclinux-h8-devel@lists.sourceforge.jp, linux-s390@vger.kernel.org,
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        linux-csky@vger.kernel.org, linux-mm@kvack.org,
        linux-m68k@lists.linux-m68k.org, openrisc@lists.librecores.org,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-snps-arc@lists.infradead.org, linuxppc-dev@lists.ozlabs.org,
        linux-riscv@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2 00/15] init_mm: cleanup ARCH's text/data/brk setup code
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On Mon, Jun 07, 2021 at 07:48:54AM +0200, Christophe Leroy wrote:
> Hi Kefeng,
> 
> What you could do is to define a __weak function that architectures can
> override and call that function from mm_init() as suggested by Mike,

The problem with weak functions is that they bloat the kernel. Each
time a weak function is overriden, it becomes dead unreachable code
within the kernel image.

At some point we're probabily going to have to enable -ffunction-sections
to (hopefully) allow the dead code to be discarded.

-- 
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