From 5c4b0dfa8690edd61030bfd328e9d0e1bb342b1a Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Mon, 5 Jul 2021 16:15:56 +0200 Subject: [PATCH 485/552] drm/vc4: hdmi: Only call into DRM framework if registered Our hotplug handler will currently call the drm_kms_helper_hotplug_event every time a hotplug interrupt is called. However, since the device is registered after all the drivers have finished their bind callback, we have a window between when we install our interrupt handler and when drm_dev_register() is eventually called where our handler can run and call drm_kms_helper_hotplug_event but the device hasn't been registered yet, causing a null pointer dereference. Fix this by making sure we only call drm_kms_helper_hotplug_event if our device has been properly registered. Fixes: f4790083c7c2 ("drm/vc4: hdmi: Rely on interrupts to handle hotplug") Signed-off-by: Maxime Ripard --- drivers/gpu/drm/vc4/vc4_hdmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 55fca8d53d14..b3219755240e 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -2156,7 +2156,7 @@ static irqreturn_t vc4_hdmi_hpd_irq_thread(int irq, void *priv) struct vc4_hdmi *vc4_hdmi = priv; struct drm_device *dev = vc4_hdmi->connector.dev; - if (dev) + if (dev && dev->registered) drm_kms_helper_hotplug_event(dev); return IRQ_HANDLED; -- 2.33.0