Re: [PATCH 37/51] drm/rockchip: Drop explicit drm_mode_config_cleanup call

From: Francesco Lavra <francescolavra.fl@gmail.com>
To: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>,
	Sandy Huang <hjc@rock-chips.com>,
	DRI Development <dri-devel@lists.freedesktop.org>,
	linux-rockchip@lists.infradead.org,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Daniel Vetter <daniel.vetter@intel.com>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 37/51] drm/rockchip: Drop explicit drm_mode_config_cleanup call
Date: Mon, 24 Feb 2020 20:13:10 +0100	[thread overview]
Message-ID: <CAOau3s8hWzD6xc6grZJr+yjtXuW1g=E_8tPigOUk-cJEQ8-JfQ@mail.gmail.com> (raw)
In-Reply-To: <20200221210319.2245170-38-daniel.vetter@ffwll.ch>

On Fri, Feb 21, 2020 at 10:04 PM Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
>
> It's (almost, there's some iommu stuff without significance) right
> above the drm_dev_put().
>
> This is made possible by a preceeding patch which added a drmm_
> cleanup action to drm_mode_config_init(), hence all we need to do to
> ensure that drm_mode_config_cleanup() is run on final drm_device
> cleanup is check the new error code for _init().
>
> Aside: Another driver with a bit much devm_kzalloc, which should
> probably use drmm_kzalloc instead ...
>
> v2: Explain why this cleanup is possible (Laurent).
>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> Cc: Sandy Huang <hjc@rock-chips.com>
> Cc: "Heiko Stübner" <heiko@sntech.de>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-rockchip@lists.infradead.org
> ---
>  drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> index 20ecb1508a22..d0eba21eebc9 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> @@ -135,7 +135,9 @@ static int rockchip_drm_bind(struct device *dev)
>         if (ret)
>                 goto err_free;
>
> -       drm_mode_config_init(drm_dev);
> +       ret = drm_mode_config_init(drm_dev);
> +       if (ret)
> +               goto err_free;

Shouldn't the goto label be err_mode_config_cleanup here? Otherwise
this error path misses the call to rockchip_iommu_cleanup().

>
>         rockchip_drm_mode_config_init(drm_dev);
>
> @@ -174,11 +176,8 @@ static int rockchip_drm_bind(struct device *dev)
>  err_unbind_all:
>         component_unbind_all(dev, drm_dev);
>  err_mode_config_cleanup:
> -       drm_mode_config_cleanup(drm_dev);
>         rockchip_iommu_cleanup(drm_dev);
>  err_free:
> -       drm_dev->dev_private = NULL;
> -       dev_set_drvdata(dev, NULL);
>         drm_dev_put(drm_dev);
>         return ret;
>  }

On Fri, Feb 21, 2020 at 10:04 PM Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
>
> It's (almost, there's some iommu stuff without significance) right
> above the drm_dev_put().
>
> This is made possible by a preceeding patch which added a drmm_
> cleanup action to drm_mode_config_init(), hence all we need to do to
> ensure that drm_mode_config_cleanup() is run on final drm_device
> cleanup is check the new error code for _init().
>
> Aside: Another driver with a bit much devm_kzalloc, which should
> probably use drmm_kzalloc instead ...
>
> v2: Explain why this cleanup is possible (Laurent).
>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> Cc: Sandy Huang <hjc@rock-chips.com>
> Cc: "Heiko Stübner" <heiko@sntech.de>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-rockchip@lists.infradead.org
> ---
>  drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> index 20ecb1508a22..d0eba21eebc9 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> @@ -135,7 +135,9 @@ static int rockchip_drm_bind(struct device *dev)
>         if (ret)
>                 goto err_free;
>
> -       drm_mode_config_init(drm_dev);
> +       ret = drm_mode_config_init(drm_dev);
> +       if (ret)
> +               goto err_free;
>
>         rockchip_drm_mode_config_init(drm_dev);
>
> @@ -174,11 +176,8 @@ static int rockchip_drm_bind(struct device *dev)
>  err_unbind_all:
>         component_unbind_all(dev, drm_dev);
>  err_mode_config_cleanup:
> -       drm_mode_config_cleanup(drm_dev);
>         rockchip_iommu_cleanup(drm_dev);
>  err_free:
> -       drm_dev->dev_private = NULL;
> -       dev_set_drvdata(dev, NULL);
>         drm_dev_put(drm_dev);
>         return ret;
>  }
> @@ -194,11 +193,8 @@ static void rockchip_drm_unbind(struct device *dev)
>
>         drm_atomic_helper_shutdown(drm_dev);
>         component_unbind_all(dev, drm_dev);
> -       drm_mode_config_cleanup(drm_dev);
>         rockchip_iommu_cleanup(drm_dev);
>
> -       drm_dev->dev_private = NULL;
> -       dev_set_drvdata(dev, NULL);
>         drm_dev_put(drm_dev);
>  }
>
> --
> 2.24.1
>
>
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip
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