On Thu, 2024-01-04 at 10:29 +0200, Imre Deak wrote: > After an HPD IRQ storm on a connector intel_hpd_irq_storm_detect() > will > set the connector's HPD pin state to HPD_MARK_DISABLED and the IRQ > gets > disabled. Subsequently intel_hpd_irq_storm_switch_to_polling() will > enable polling for these connectors, setting the pin state to > HPD_DISABLED, but only if the connector's base.polled field is set to > DRM_CONNECTOR_POLL_HPD. intel_hpd_irq_storm_reenable_work() will > reenable the IRQ - after 2 minutes - if the pin state is > HPD_DISABLED. > > The connectors will be created with their base.polled field set to 0, > which gets initialized only later in i915_hpd_poll_init_work() (using > intel_connector::polled). If a storm is detected on a connector after > it's created and IRQs are enabled on it - by intel_hpd_init() - and > before its bease.polled field is initialized in the above work, the > connector's HPD pin will stay in the HPD_MARK_DISABLED state - > leaving > the IRQ disabled indefinitely - and polling will not get enabled on > it as > intended. > > I can't see a reason for initializing base.polled in a delayed > manner, > so do this already when creating the connector, to prevent the above > race condition. To me it looks like intel_connector::polled is used just to store original drm_connector::polled value and restore it in intel_hpd_irq_storm_reenable_work: if (connector->base.polled != connector->polled) drm_dbg(&dev_priv->drm, "Reenabling HPD on connector %s\n", connector->base.name); connector->base.polled = connector->polled; >From this perspective it is right thing to do to initialize connector- >base.polled as you are doing in this patch. Reviewed-by: Jouni Högander <jouni.hogander@xxxxxxxxx> > > Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_crt.c | 1 + > drivers/gpu/drm/i915/display/intel_dp.c | 1 + > drivers/gpu/drm/i915/display/intel_dvo.c | 1 + > drivers/gpu/drm/i915/display/intel_hdmi.c | 1 + > drivers/gpu/drm/i915/display/intel_sdvo.c | 2 ++ > drivers/gpu/drm/i915/display/intel_tv.c | 1 + > 6 files changed, 7 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_crt.c > b/drivers/gpu/drm/i915/display/intel_crt.c > index abaacea5c2cc4..b330337b842a4 100644 > --- a/drivers/gpu/drm/i915/display/intel_crt.c > +++ b/drivers/gpu/drm/i915/display/intel_crt.c > @@ -1069,6 +1069,7 @@ void intel_crt_init(struct drm_i915_private > *dev_priv) > } else { > intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT; > } > + intel_connector->base.polled = intel_connector->polled; > > if (HAS_DDI(dev_priv)) { > assert_port_valid(dev_priv, PORT_E); > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > b/drivers/gpu/drm/i915/display/intel_dp.c > index 9ff0cbd9c0df5..fed649af8fc85 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > @@ -6469,6 +6469,7 @@ intel_dp_init_connector(struct > intel_digital_port *dig_port, > connector->interlace_allowed = true; > > intel_connector->polled = DRM_CONNECTOR_POLL_HPD; > + intel_connector->base.polled = intel_connector->polled; > > intel_connector_attach_encoder(intel_connector, > intel_encoder); > > diff --git a/drivers/gpu/drm/i915/display/intel_dvo.c > b/drivers/gpu/drm/i915/display/intel_dvo.c > index 9111e9d46486d..83898ba493d16 100644 > --- a/drivers/gpu/drm/i915/display/intel_dvo.c > +++ b/drivers/gpu/drm/i915/display/intel_dvo.c > @@ -536,6 +536,7 @@ void intel_dvo_init(struct drm_i915_private > *i915) > if (intel_dvo->dev.type == INTEL_DVO_CHIP_TMDS) > connector->polled = DRM_CONNECTOR_POLL_CONNECT | > DRM_CONNECTOR_POLL_DISCONNECT; > + connector->base.polled = connector->polled; > > drm_connector_init_with_ddc(&i915->drm, &connector->base, > &intel_dvo_connector_funcs, > diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c > b/drivers/gpu/drm/i915/display/intel_hdmi.c > index eedef8121ff7c..55048c56bc527 100644 > --- a/drivers/gpu/drm/i915/display/intel_hdmi.c > +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c > @@ -3017,6 +3017,7 @@ void intel_hdmi_init_connector(struct > intel_digital_port *dig_port, > connector->ycbcr_420_allowed = true; > > intel_connector->polled = DRM_CONNECTOR_POLL_HPD; > + intel_connector->base.polled = intel_connector->polled; > > if (HAS_DDI(dev_priv)) > intel_connector->get_hw_state = > intel_ddi_connector_get_hw_state; > diff --git a/drivers/gpu/drm/i915/display/intel_sdvo.c > b/drivers/gpu/drm/i915/display/intel_sdvo.c > index 9218047495fb4..4e4a87f841787 100644 > --- a/drivers/gpu/drm/i915/display/intel_sdvo.c > +++ b/drivers/gpu/drm/i915/display/intel_sdvo.c > @@ -2805,6 +2805,7 @@ intel_sdvo_dvi_init(struct intel_sdvo > *intel_sdvo, u16 type) > } else { > intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT > | DRM_CONNECTOR_POLL_DISCONNECT; > } > + intel_connector->base.polled = intel_connector->polled; > encoder->encoder_type = DRM_MODE_ENCODER_TMDS; > connector->connector_type = DRM_MODE_CONNECTOR_DVID; > > @@ -2880,6 +2881,7 @@ intel_sdvo_analog_init(struct intel_sdvo > *intel_sdvo, u16 type) > intel_connector = &intel_sdvo_connector->base; > connector = &intel_connector->base; > intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT; > + intel_connector->base.polled = intel_connector->polled; > encoder->encoder_type = DRM_MODE_ENCODER_DAC; > connector->connector_type = DRM_MODE_CONNECTOR_VGA; > > diff --git a/drivers/gpu/drm/i915/display/intel_tv.c > b/drivers/gpu/drm/i915/display/intel_tv.c > index d4386cb3569e0..f3598fe39fda5 100644 > --- a/drivers/gpu/drm/i915/display/intel_tv.c > +++ b/drivers/gpu/drm/i915/display/intel_tv.c > @@ -1990,6 +1990,7 @@ intel_tv_init(struct drm_i915_private > *dev_priv) > * More recent chipsets favour HDMI rather than integrated S- > Video. > */ > intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT; > + intel_connector->base.polled = intel_connector->polled; > > drm_connector_init(&dev_priv->drm, connector, > &intel_tv_connector_funcs, > DRM_MODE_CONNECTOR_SVIDEO);