Re: [PATCH v2 2/2] drm/panthor: Fix OPP refcnt leaks in devfreq initialisation

From: Steven Price
Date: Thu Oct 03 2024 - 10:51:38 EST


On 03/10/2024 14:30, Adrián Larumbe wrote:
> Make sure in case of errors between the first fetch of an OPP in
> panthor_devfreq_init and its successive put, the error path decrements its
> reference count to avoid OPP object leaks when removing the device.
>
> Signed-off-by: Adrián Larumbe <adrian.larumbe@xxxxxxxxxxxxx>
> Fixes: fac9b22df4b1 ("drm/panthor: Add the devfreq logical block")

Reviewed-by: Steven Price <steven.price@xxxxxxx>

> ---
> drivers/gpu/drm/panthor/panthor_devfreq.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.c b/drivers/gpu/drm/panthor/panthor_devfreq.c
> index 9d0f891b9b53..ce0ac4563f65 100644
> --- a/drivers/gpu/drm/panthor/panthor_devfreq.c
> +++ b/drivers/gpu/drm/panthor/panthor_devfreq.c
> @@ -197,7 +197,7 @@ int panthor_devfreq_init(struct panthor_device *ptdev)
> if (ret && ret != -ENODEV) {
> if (ret != -EPROBE_DEFER)
> DRM_DEV_ERROR(dev, "Couldn't retrieve/enable sram supply\n");
> - return ret;
> + goto opp_err;
> }
>
> /*
> @@ -207,7 +207,7 @@ int panthor_devfreq_init(struct panthor_device *ptdev)
> ret = dev_pm_opp_set_opp(dev, opp);
> if (ret) {
> DRM_DEV_ERROR(dev, "Couldn't set recommended OPP\n");
> - return ret;
> + goto opp_err;
> }
>
> dev_pm_opp_put(opp);
> @@ -242,6 +242,10 @@ int panthor_devfreq_init(struct panthor_device *ptdev)
> DRM_DEV_INFO(dev, "Failed to register cooling device\n");
>
> return 0;
> +
> +opp_err:
> + dev_pm_opp_put(opp);
> + return ret;
> }
>
> int panthor_devfreq_resume(struct panthor_device *ptdev)