linux-kernel - Re: [PATCH] msm: msm_fb: Add remove function for platform driver for clean unloading

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Tue, 26 Aug 2014 14:19:18 +0300
From:	Tomi Valkeinen <tomi.valkeinen@...com>
To:	Pramod Gurav <pramod.gurav@...rtplayin.com>,
	<linux-fbdev@...r.kernel.org>, <linux-kernel@...r.kernel.org>
CC:	Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>,
	Stephen Boyd <sboyd@...eaurora.org>,
	Jingoo Han <jg1.han@...sung.com>,
	Rob Clark <robdclark@...il.com>
Subject: Re: [PATCH] msm: msm_fb: Add remove function for platform driver
 for clean unloading

Hi,

On 04/08/14 17:43, Pramod Gurav wrote:
> This adds a  remove function to platform driver structure so that
> resources are released when driver is unloaded.
> 
> Moved kzalloc to use managed resource and adds a return check if failed.

Please split this patch into two. You change two unrelated things here,
the unloading and the kzalloc part.

> CC: Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>
> CC: Tomi Valkeinen <tomi.valkeinen@...com>
> CC: Stephen Boyd <sboyd@...eaurora.org>
> CC: Jingoo Han <jg1.han@...sung.com>
> CC: Rob Clark <robdclark@...il.com>
> 
> Signed-off-by: Pramod Gurav <pramod.gurav@...rtplayin.com>
> ---
>  drivers/video/fbdev/msm/msm_fb.c |   28 +++++++++++++++++++++++++---
>  1 file changed, 25 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/video/fbdev/msm/msm_fb.c b/drivers/video/fbdev/msm/msm_fb.c
> index 1374803..ac277e2 100644
> --- a/drivers/video/fbdev/msm/msm_fb.c
> +++ b/drivers/video/fbdev/msm/msm_fb.c
> @@ -553,6 +553,7 @@ static int msmfb_probe(struct platform_device *pdev)
>  	fb = framebuffer_alloc(sizeof(struct msmfb_info), &pdev->dev);
>  	if (!fb)
>  		return -ENOMEM;
> +
>  	msmfb = fb->par;
>  	msmfb->fb = fb;
>  	msmfb->panel = panel;
> @@ -569,8 +570,13 @@ static int msmfb_probe(struct platform_device *pdev)
>  	mutex_init(&msmfb->panel_init_lock);
>  	init_waitqueue_head(&msmfb->frame_wq);
>  	INIT_WORK(&msmfb->resume_work, power_on_panel);
> -	msmfb->black = kzalloc(msmfb->fb->var.bits_per_pixel*msmfb->xres,
> -			       GFP_KERNEL);
> +	msmfb->black = devm_kzalloc(&pdev->dev,
> +				    msmfb->fb->var.bits_per_pixel*msmfb->xres,
> +				    GFP_KERNEL);
> +	if (!msmfb->black) {
> +		ret = -ENOMEM;
> +		goto error_register_framebuffer;
> +	}
>  
>  	printk(KERN_INFO "msmfb_probe() installing %d x %d panel\n",
>  	       msmfb->xres, msmfb->yres);
> @@ -589,6 +595,8 @@ static int msmfb_probe(struct platform_device *pdev)
>  
>  	msmfb->sleeping = WAKING;
>  
> +	platform_set_drvdata(pdev, msmfb);
> +
>  	return 0;
>  
>  error_register_framebuffer:
> @@ -598,13 +606,27 @@ error_setup_fbmem:
>  	return ret;
>  }
>  
> +static int msmfb_remove(struct platform_device *pdev)
> +{
> +	struct msmfb_info *msmfb = NULL;

No need to initialize to NULL, msmfb is initialized always below.

> +
> +	msmfb = platform_get_drvdata(pdev);
> +	if (msmfb) {

Can msmfb ever be NULL here? If I'm not mistaken, remove is only called
if the probe had succeeded. And if probe had succeeded, the drvdata is
always set to a proper pointer to msmfb_info.

 Tomi



Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)