[PATCH 4/4] efifb: Disallow manual bind and unbind

[PATCH 4/4] efifb: Disallow manual bind and unbind

[Andy Lutomirski]

Both were buggy: bind would happily scribble over a real graphics
device and unbind wouldn't destroy the framebuffer.  Hotplugging
efifb makes no sense anyway, so just disable it.

As an added benefit, we save some runtime memory.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
---
 drivers/video/efifb.c |   21 ++++++++++++++-------
 1 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/video/efifb.c b/drivers/video/efifb.c
index 39bbfa9..f67717e 100644
--- a/drivers/video/efifb.c
+++ b/drivers/video/efifb.c
@@ -331,7 +331,7 @@ static int __init efifb_setup(char *options)
 	return 0;
 }
 
-static int __devinit efifb_probe(struct platform_device *dev)
+static int __init efifb_probe(struct platform_device *dev)
 {
 	struct fb_info *info;
 	int err;
@@ -501,7 +501,6 @@ err_release_mem:
 }
 
 static struct platform_driver efifb_driver = {
-	.probe	= efifb_probe,
 	.driver	= {
 		.name	= "efifb",
 	},
@@ -532,13 +531,21 @@ static int __init efifb_init(void)
 	if (!screen_info.lfb_linelength)
 		return -ENODEV;
 
-	ret = platform_driver_register(&efifb_driver);
+	ret = platform_device_register(&efifb_device);
+	if (ret)
+		return ret;
 
-	if (!ret) {
-		ret = platform_device_register(&efifb_device);
-		if (ret)
-			platform_driver_unregister(&efifb_driver);
+	/*
+	 * This is not just an optimization.  We will interfere
+	 * with a real driver if we get reprobed, so don't allow
+	 * it.
+	 */
+	ret = platform_driver_probe(&efifb_driver, efifb_probe);
+	if (ret) {
+		platform_device_unregister(&efifb_driver);
+		return ret;
 	}
+
 	return ret;
 }
 module_init(efifb_init);
-- 
1.7.5.1

Re: [PATCH 4/4] efifb: Disallow manual bind and unbind

[Peter Jones]

On 05/26/2011 10:13 AM, Andy Lutomirski wrote:
> Both were buggy: bind would happily scribble over a real graphics
> device and unbind wouldn't destroy the framebuffer.  Hotplugging
> efifb makes no sense anyway, so just disable it.
> 
> As an added benefit, we save some runtime memory.
> 
> Signed-off-by: Andy Lutomirski <luto@mit.edu>

Signed-off-by: Peter Jones <pjones@redhat.com>

> ---
>  drivers/video/efifb.c |   21 ++++++++++++++-------
>  1 files changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/video/efifb.c b/drivers/video/efifb.c
> index 39bbfa9..f67717e 100644
> --- a/drivers/video/efifb.c
> +++ b/drivers/video/efifb.c
> @@ -331,7 +331,7 @@ static int __init efifb_setup(char *options)
>  	return 0;
>  }
>  
> -static int __devinit efifb_probe(struct platform_device *dev)
> +static int __init efifb_probe(struct platform_device *dev)
>  {
>  	struct fb_info *info;
>  	int err;
> @@ -501,7 +501,6 @@ err_release_mem:
>  }
>  
>  static struct platform_driver efifb_driver = {
> -	.probe	= efifb_probe,
>  	.driver	= {
>  		.name	= "efifb",
>  	},
> @@ -532,13 +531,21 @@ static int __init efifb_init(void)
>  	if (!screen_info.lfb_linelength)
>  		return -ENODEV;
>  
> -	ret = platform_driver_register(&efifb_driver);
> +	ret = platform_device_register(&efifb_device);
> +	if (ret)
> +		return ret;
>  
> -	if (!ret) {
> -		ret = platform_device_register(&efifb_device);
> -		if (ret)
> -			platform_driver_unregister(&efifb_driver);
> +	/*
> +	 * This is not just an optimization.  We will interfere
> +	 * with a real driver if we get reprobed, so don't allow
> +	 * it.
> +	 */
> +	ret = platform_driver_probe(&efifb_driver, efifb_probe);
> +	if (ret) {
> +		platform_device_unregister(&efifb_driver);
> +		return ret;
>  	}
> +
>  	return ret;
>  }
>  module_init(efifb_init);


-- 
        Peter

If you're not part of the solution, then you're part of the precipitate.

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