Re: [PATCH 2/4] arm: dump: no need to check return value of debugfs_create functions

[Laura Abbott]

On 1/22/19 6:41 AM, Greg Kroah-Hartman wrote:
> When calling debugfs functions, there is no need to ever check the
> return value.  The function can work or not, but the code logic should
> never do something different based on this.
>
> Cc: Russell King <linux@xxxxxxxxxxxxxxx>
> Cc: Jinbum Park <jinb.park7@xxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Laura Abbott <labbott@xxxxxxxxxx>

Acked-by: Laura Abbott <labbott@xxxxxxxxxx>

> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
>   arch/arm/include/asm/ptdump.h | 9 +++------
>   arch/arm/mm/dump.c            | 4 ++--
>   arch/arm/mm/ptdump_debugfs.c  | 8 ++------
>   3 files changed, 7 insertions(+), 14 deletions(-)
>
> diff --git a/arch/arm/include/asm/ptdump.h b/arch/arm/include/asm/ptdump.h
> index 3ebf9718288d..0c2d3d0d4cc6 100644
> --- a/arch/arm/include/asm/ptdump.h
> +++ b/arch/arm/include/asm/ptdump.h
> @@ -21,13 +21,10 @@ struct ptdump_info {
>   
>   void ptdump_walk_pgd(struct seq_file *s, struct ptdump_info *info);
>   #ifdef CONFIG_ARM_PTDUMP_DEBUGFS
> -int ptdump_debugfs_register(struct ptdump_info *info, const char *name);
> +void ptdump_debugfs_register(struct ptdump_info *info, const char *name);
>   #else
> -static inline int ptdump_debugfs_register(struct ptdump_info *info,
> -					const char *name)
> -{
> -	return 0;
> -}
> +static inline void ptdump_debugfs_register(struct ptdump_info *info,
> +					   const char *name) { }
>   #endif /* CONFIG_ARM_PTDUMP_DEBUGFS */
>   
>   void ptdump_check_wx(void);
> diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
> index 084779c5c893..eb385a500ed0 100644
> --- a/arch/arm/mm/dump.c
> +++ b/arch/arm/mm/dump.c
> @@ -450,7 +450,7 @@ void ptdump_check_wx(void)
>   static int ptdump_init(void)
>   {
>   	ptdump_initialize();
> -	return ptdump_debugfs_register(&kernel_ptdump_info,
> -					"kernel_page_tables");
> +	ptdump_debugfs_register(&kernel_ptdump_info, "kernel_page_tables");
> +	return 0;
>   }
>   __initcall(ptdump_init);
> diff --git a/arch/arm/mm/ptdump_debugfs.c b/arch/arm/mm/ptdump_debugfs.c
> index be8d87be4b93..598b636615a2 100644
> --- a/arch/arm/mm/ptdump_debugfs.c
> +++ b/arch/arm/mm/ptdump_debugfs.c
> @@ -24,11 +24,7 @@ static const struct file_operations ptdump_fops = {
>   	.release	= single_release,
>   };
>   
> -int ptdump_debugfs_register(struct ptdump_info *info, const char *name)
> +void ptdump_debugfs_register(struct ptdump_info *info, const char *name)
>   {
> -	struct dentry *pe;
> -
> -	pe = debugfs_create_file(name, 0400, NULL, info, &ptdump_fops);
> -	return pe ? 0 : -ENOMEM;
> -
> +	debugfs_create_file(name, 0400, NULL, info, &ptdump_fops);
>   }