linux-kernel - Re: [PATCH v4 1/2] drm/panfrost: Add missing OPP table refcnt decremental

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]

Message-ID: <7c4a3ed4-d37b-4de9-af53-5f022b5170c0@arm.com>
Date: Wed, 6 Nov 2024 16:00:31 +0000
From: Steven Price <steven.price@....com>
To: Adrián Larumbe <adrian.larumbe@...labora.com>,
 Boris Brezillon <boris.brezillon@...labora.com>,
 Rob Herring <robh@...nel.org>,
 Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
 Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>,
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
 AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
Cc: kernel@...labora.com, Liviu Dudau <liviu.dudau@....com>,
 dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 1/2] drm/panfrost: Add missing OPP table refcnt
 decremental

On 05/11/2024 20:54, Adrián Larumbe wrote:
> Commit f11b0417eec2 ("drm/panfrost: Add fdinfo support GPU load metrics")
> retrieves the OPP for the maximum device clock frequency, but forgets to
> keep the reference count balanced by putting the returned OPP object. This
> eventually leads to an OPP core warning when removing the device.
> 
> Fix it by putting OPP objects as many times as they're retrieved.
> 
> Also remove an unnecessary whitespace.
> 
> Signed-off-by: Adrián Larumbe <adrian.larumbe@...labora.com>
> Fixes: f11b0417eec2 ("drm/panfrost: Add fdinfo support GPU load metrics")
> Reviewed-by: Steven Price <steven.price@....com>
> Reviewed-by: Liviu Dudau <liviu.dudau@....com>

Both pushed to drm-misc-next.

Thanks,
Steve

> ---
>  drivers/gpu/drm/panfrost/panfrost_devfreq.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> index 2d30da38c2c3..3385fd3ef41a 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> @@ -38,7 +38,7 @@ static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
>  		return PTR_ERR(opp);
>  	dev_pm_opp_put(opp);
>  
> -	err =  dev_pm_opp_set_rate(dev, *freq);
> +	err = dev_pm_opp_set_rate(dev, *freq);
>  	if (!err)
>  		ptdev->pfdevfreq.current_frequency = *freq;
>  
> @@ -182,6 +182,7 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
>  	 * if any and will avoid a switch off by regulator_late_cleanup()
>  	 */
>  	ret = dev_pm_opp_set_opp(dev, opp);
> +	dev_pm_opp_put(opp);
>  	if (ret) {
>  		DRM_DEV_ERROR(dev, "Couldn't set recommended OPP\n");
>  		return ret;
> 
> base-commit: aadcf584583ca9833b4fb2140a4f437569ddbcd7