> [Severity: High] This is a pre-existing issue, but by adding this
> error path, the patch exposes it further. Does returning an error
> here without cancelling hdmi->hpd_work risk a use-after-free?

Thanks for taking a look.

The window you describe does exist, but it is not introduced or
widened by this patch: hdmi->hpd_work is initialized and the HPD
interrupt requested early in dw_hdmi_qp_rockchip_bind(), and the
function already has several error returns after the interrupt is
live -- encoder init, dw_hdmi_qp_bind() and drm_bridge_connector_init()
-- none of which cancel the delayed work. This patch adds one more
return immediately after the last of those, following the function's
existing error-handling pattern.
Since the cancellation gap is common to all of bind()'s error paths,
I think the right fix is a separate patch addressing all of them at
once (e.g. switching to devm_delayed_work_autocancel() or a devres
action) rather than special-casing the new return. I'm happy to send
that as a follow-up.

Igor


On Tue, Jul 14, 2026 at 10:40 PM <[email protected]> wrote:
>
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) 
> to consider:
>
> Pre-existing issues:
> - [High] Returning an error from `dw_hdmi_qp_rockchip_bind()` without 
> cancelling `hdmi->hpd_work` leads to a Use-After-Free when the delayed work 
> or HPD interrupt fires.
> --
>
> --- Patch [1]: [PATCH] drm/rockchip: dw_hdmi_qp: attach the HDMI Colorspace 
> connector property ---
> commit 77d2f0e8bc60d50755aec22dee119ad08bb92b3c
> Author: Igor Paunovic <[email protected]>
>
> drm/rockchip: dw_hdmi_qp: attach the HDMI Colorspace connector property
>
> This commit creates and attaches the standard HDMI colorspace property
> after the bridge connector is initialised. This allows userspace to request
> BT.2020 colorimetry and enables wide-gamut/HDR output on RK3588.
>
> > diff --git a/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c 
> > b/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c
> > --- a/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c
> > +++ b/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c
> [ ... ]
> > @@ -695,6 +695,20 @@ static int dw_hdmi_qp_rockchip_bind(struct device 
> > *dev, struct device *master,
> >               return dev_err_probe(hdmi->dev, PTR_ERR(connector),
> >                                    "Failed to init bridge connector\n");
> >
> > +     /*
> > +      * Attach the HDMI Colorspace property. The HDMI connector framework
> > +      * already consumes conn_state->colorspace for the AVI infoframe
> > +      * (drm_hdmi_avi_infoframe_colorimetry()), and HDR_OUTPUT_METADATA and
> > +      * max bpc are attached by drmm_connector_hdmi_init(), but without the
> > +      * Colorspace property userspace cannot request BT.2020 signalling,
> > +      * which keeps wide-gamut/HDR output unavailable. Passing 0 selects
> > +      * the full HDMI colorspace set defined by the core.
> > +      */
> > +     ret = drm_mode_create_hdmi_colorspace_property(connector, 0);
> > +     if (ret)
> > +             return ret;
>
> [Severity: High]
> This is a pre-existing issue, but by adding this error path, the patch
> exposes it further. Does returning an error here without cancelling
> hdmi->hpd_work risk a use-after-free?
>
> If a hardware HPD interrupt fires right before the devres cleanup
> unregisters the IRQ, hdmi->hpd_work can get queued. The DRM master
> teardown then frees hdmi (which was allocated via drmm_kzalloc),
> leaving the delayed work to execute later with a dangling pointer:
>
> drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c:dw_hdmi_qp_rk3588_hpd_work() {
>         struct rockchip_hdmi_qp *hdmi = container_of(work,
>                                                      struct rockchip_hdmi_qp,
>                                                      hpd_work.work);
>         struct drm_device *drm = hdmi->encoder.encoder.dev;
>         ...
> }
>
> Could we ensure that the delayed work is properly cancelled before
> returning errors from dw_hdmi_qp_rockchip_bind()?
>
> > +     drm_connector_attach_colorspace_property(connector);
> >
> >       return 0;
> >  }
>
> --
> Sashiko AI review · 
> https://sashiko.dev/#/patchset/[email protected]?part=1

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