Date:   Fri, 3 Mar 2023 14:11:45 -0800
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     ye.xingchen@zte.com.cn
Cc:     keescook@chromium.org, yzaikin@google.com,
        akpm@linux-foundation.org, linmiaohe@huawei.com,
        chi.minghao@zte.com.cn, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH] mm: =?iso-8859-1?Q?compaction?=
 =?iso-8859-1?Q?=3A_limit_illegal_input_parameters_of=A0compact=5Fmemor?=
 =?iso-8859-1?Q?y?= interface
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Sender: Luis Chamberlain <mcgrof@infradead.org>
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On Fri, Mar 03, 2023 at 08:44:41AM +0800, ye.xingchen@zte.com.cn wrote:
> From: Minghao Chi <chi.minghao@zte.com.cn>
> 
> Available only when CONFIG_COMPACTION is set. When 1 is written to
> the file, all zones are compacted such that free memory is available
> in contiguous blocks where possible.
> But echo others-parameter > compact_memory, this function will be
> triggered by writing parameters to the interface.
> 
> Applied this patch,
> sh/$ echo 1.1 > /proc/sys/vm/compact_memory
> sh/$ sh: write error: Invalid argument
> The start and end time of printing triggering compact_memory.
> 
> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
> Signed-off-by: Ye Xingchen <ye.xingchen@zte.com.cn>

Do a huge favor and while you're at it split this into two patches,
one which takes this out of kernel/sysctl.c and move it to
mm/compaction.c and a second one that does your change here.

Since kernel/sysctl.c is being trimmed you can base your changes on
sysctl-next [0] and I'm happy to take in there if Andrew agrees to it.

[0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=sysctl-next

  Luis