linux-kernel - Re: [PATCH] drivers: video: Remove useless checks

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Message-ID: <4DDCFA6F.2020801@canonical.com>
Date:	Wed, 25 May 2011 06:47:43 -0600
From:	Tim Gardner <tim.gardner@...onical.com>
To:	Maxin B John <maxin.john@...il.com>
CC:	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	airlied@...hat.com, lethal@...ux-sh.org, james@...anarts.com,
	error27@...il.com, randy.dunlap@...cle.com
Subject: Re: [PATCH] drivers: video: Remove useless checks

On 05/19/2011 12:27 PM, Maxin B John wrote:
> Comparing unsigned less than zero will never be true.
> Removing similar checks from 'fbmem.c' and 'fbcmap.c'.
>
> Please let me know your comments.
>
> Signed-off-by: Maxin B. John<maxin.john@...il.com>
> ---
> diff --git a/drivers/video/fbcmap.c b/drivers/video/fbcmap.c
> index 5c3960d..15cf8fc 100644
> --- a/drivers/video/fbcmap.c
> +++ b/drivers/video/fbcmap.c
> @@ -285,8 +285,7 @@ int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info)
>   		rc = -ENODEV;
>   		goto out;
>   	}
> -	if (cmap->start<  0 || (!info->fbops->fb_setcolreg&&
> -				!info->fbops->fb_setcmap)) {
> +	if (!info->fbops->fb_setcolreg&&  !info->fbops->fb_setcmap) {
>   		rc = -EINVAL;
>   		goto out1;
>   	}
> diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
> index 5aac00e..9edca4d 100644
> --- a/drivers/video/fbmem.c
> +++ b/drivers/video/fbmem.c
> @@ -1143,7 +1143,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
>   			return -EFAULT;
>   		if (con2fb.console<  1 || con2fb.console>  MAX_NR_CONSOLES)
>   			return -EINVAL;
> -		if (con2fb.framebuffer<  0 || con2fb.framebuffer>= FB_MAX)
> +		if (con2fb.framebuffer>= FB_MAX)
>   			return -EINVAL;
>   		if (!registered_fb[con2fb.framebuffer])
>   			request_module("fb%d", con2fb.framebuffer);
>

Looks right to me, though there are other places that suffer from the 
same issue. See fb_set_cmap() and its use of 'int start' and cmap->start.

rtg
-- 
Tim Gardner tim.gardner@...onical.com
--
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