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Date:   Mon, 20 Jul 2020 14:52:34 -0500
From:   Corey Minyard <minyard@acm.org>
To:     Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc:     arnd@arndb.de, gregkh@linuxfoundation.org,
        openipmi-developer@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, guohanjun@huawei.com
Subject: Re: [PATCH] ipmi/watchdog: add missing newlines when printing
 parameters by sysfs
Message-ID: <20200720195234.GC2952@minyard.net>
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On Mon, Jul 20, 2020 at 10:03:25AM +0800, Xiongfeng Wang wrote:
> When I cat some ipmi_watchdog parameters by sysfs, it displays as
> follows. It's better to add a newline for easy reading.
> 
> root@(none):/# cat /sys/module/ipmi_watchdog/parameters/action
> resetroot@(none):/# cat /sys/module/ipmi_watchdog/parameters/preaction
> pre_noneroot@(none):/# cat /sys/module/ipmi_watchdog/parameters/preop
> preop_noneroot@(none):/#

Yeah, that's not consistent with other things displayed in the kernel.

> 
> Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
> ---
>  drivers/char/ipmi/ipmi_watchdog.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
> index 55986e1..3e05a1d 100644
> --- a/drivers/char/ipmi/ipmi_watchdog.c
> +++ b/drivers/char/ipmi/ipmi_watchdog.c
> @@ -232,12 +232,16 @@ static int set_param_str(const char *val, const struct kernel_param *kp)
>  static int get_param_str(char *buffer, const struct kernel_param *kp)
>  {
>  	action_fn fn = (action_fn) kp->arg;
> -	int       rv;
> +	int rv, len;
>  
>  	rv = fn(NULL, buffer);
>  	if (rv)
>  		return rv;
> -	return strlen(buffer);
> +
> +	len = strlen(buffer);
> +	len += sprintf(buffer + len, "\n");

sprintf is kind of overkill to stick a \n on the end of a line.  How
about:

	buffer[len++] = '\n';

Since you are returning the length, you shouldn't need to nil terminate
the string.

An unrelated question: Are you using any of the special functions of the
IPMI watchdog, like the pretimeout?

-corey

> +
> +	return len;
>  }
>  
>  
> -- 
> 1.7.12.4
>