Re: [PATCH 2/5] mm: remove watermark_boost_factor_sysctl_handler

[Kees Cook]

On Fri, Apr 24, 2020 at 08:43:35AM +0200, Christoph Hellwig wrote:
> watermark_boost_factor_sysctl_handler is just a pointless wrapper for
> proc_dointvec_minmax, so remove it and use proc_dointvec_minmax
> directly.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-Kees

> Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
> ---
>  include/linux/mmzone.h |  2 --
>  kernel/sysctl.c        |  2 +-
>  mm/page_alloc.c        | 12 ------------
>  3 files changed, 1 insertion(+), 15 deletions(-)
> 
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> index 1b9de7d220fb7..f37bb8f187fc7 100644
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -911,8 +911,6 @@ static inline int is_highmem(struct zone *zone)
>  struct ctl_table;
>  int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
>  					void __user *, size_t *, loff_t *);
> -int watermark_boost_factor_sysctl_handler(struct ctl_table *, int,
> -					void __user *, size_t *, loff_t *);
>  int watermark_scale_factor_sysctl_handler(struct ctl_table *, int,
>  					void __user *, size_t *, loff_t *);
>  extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES];
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 8a176d8727a3a..99d27acf46465 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -1491,7 +1491,7 @@ static struct ctl_table vm_table[] = {
>  		.data		= &watermark_boost_factor,
>  		.maxlen		= sizeof(watermark_boost_factor),
>  		.mode		= 0644,
> -		.proc_handler	= watermark_boost_factor_sysctl_handler,
> +		.proc_handler	= proc_dointvec_minmax,
>  		.extra1		= SYSCTL_ZERO,
>  	},
>  	{
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 69827d4fa0527..62c1550cd43ec 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -7978,18 +7978,6 @@ int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write,
>  	return 0;
>  }
>  
> -int watermark_boost_factor_sysctl_handler(struct ctl_table *table, int write,
> -	void __user *buffer, size_t *length, loff_t *ppos)
> -{
> -	int rc;
> -
> -	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
> -	if (rc)
> -		return rc;
> -
> -	return 0;
> -}
> -
>  int watermark_scale_factor_sysctl_handler(struct ctl_table *table, int write,
>  	void __user *buffer, size_t *length, loff_t *ppos)
>  {
> -- 
> 2.26.1
> 

-- 
Kees Cook