Re: [PATCH v4 02/14] drm/rockchip: vop2: Fix resource leak on vop2_enable() error path

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Use of sleeping functions in an atomic context path.
--

commit 3156fa20e2cac505ec1966277bb361639a86a353
Author: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>

drm/rockchip: vop2: Fix resource leak on vop2_enable() error path

This commit modifies vop2_enable() to return an int and gracefully unwind
resources such as clocks and runtime PM references if initialization steps 
like rockchip_drm_dma_attach_device() fail. It addresses a resource leak 
where previously the function returned void without disabling clocks or 
dropping the PM reference on error.

Link: https://lore.kernel.org/all/20260623202043.8BFE21F000E9@smtp.kernel.org/

> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
[ ... ]
> @@ -932,6 +938,17 @@ static void vop2_enable(struct vop2 *vop2)
>  		    VOP2_INT_BUS_ERRPR << 16 | VOP2_INT_BUS_ERRPR);
>  	vop2_writel(vop2, RK3568_SYS1_INT_EN,
>  		    VOP2_INT_BUS_ERRPR << 16 | VOP2_INT_BUS_ERRPR);
> +
> +	return 0;
> +
> +err_detach_dma:
> +	rockchip_drm_dma_detach_device(vop2->drm, vop2->dev);
> +err_disable_clks:
> +	vop2_core_clks_disable_unprepare(vop2);
> +err_put_pm:
> +	pm_runtime_put_sync(vop2->dev);

[Severity: High]
This is a pre-existing issue, but is it safe to execute a sleeping function
here? 

The DRM subsystem guidelines indicate that CRTC atomic_enable callbacks are
atomic context paths where sleeping is strictly forbidden. Since vop2_enable()
is called from the vop2_crtc_atomic_enable() callback, wouldn't executing
pm_runtime_put_sync() (as well as clk_prepare_enable() and
pm_runtime_resume_and_get() earlier in this function) cause system panics
such as scheduling while atomic or deadlocks during a display bring-up
or modeset?

> +
> +	return ret;
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260903-dw-hdmi-qp-yuv-v4-0-fb45bf4147eb@collabora.com?part=2